Argentina says signals detected, likely from missing submarine - <AUTHOR> https://www.reuters.com/article/us-argentina-submarine/argentina-says-signals-detected-likely-from-missing-submarine-idUSKBN1DI0M8 <comment><USER3> I took a brief excursion on a private submarine once and the list of things that could go wrong that they asked to you explicitly release them from liability for was frankly rather frightening. It really put a damper on my desire for a 'casual' submarine from US Subs.

Given the description that the seas are quite rough I hope it is a simple matter of them losing a communications mast or something along those lines.

<comment><USER4> Submarines are just about the worst when it comes to the duration from the second someone goofs up and the second where everyone's doomed.

And also the worst when it comes to the duration from the instant everyone's doomed to the instant everyone's dead.

TSorry, but that's a "no" from me, dawg.

<comment><USER5> There's surely an obvious answer to this, but assuming the goof doesn't cripple the submarine's ability to move, and ignoring issues of secrecy, is there a reason it can't just head for the surface and be there in a few hours? There's nothing like the bends here for the passengers, right?

<comment><USER6> Subs control their depth by flooding internal tanks with water (more water = sub goes deeper). They can surface very quickly (seconds to a few minutes, depending on the depth) by blowing all the water out of those tanks with compressed air.

That's assuming something hasn't gone wrong that has caused the sub to take on water somewhere other than those ballast tanks. If a portion of the sub fills with water, the empty ballast tanks may not provide enough buoyant force to lift the sub.

<comment><USER7> Correct me if I'm wrong, but I believe a neutrally buoyant, or even (a little?) negatively buoyant sub can adjust depth, perhaps even surface?, under its own power.

<comment><USER8> It can, but there are actually very few of those types of subs around and they tend to be limited to research and recreation. Keeping several hundred tons neurally buoyant is kinda hard and if the sub has positive buoyancy then it requires propulsion to stay down or else an elevator ride to the surface is a one-way trip. Needing constant propulsion is bad for a military sub, and being stranded on the surface after any sort of emergency surface action (even a test) would also be a bad thing.

</comment></comment></comment></comment></comment></comment><comment><USER9> Ars Technica ran an article [0] yesterday that had more info and details on the sub, as well as some info about NASA's involvement (P-3 aircraft participating in the search).

[0]: [https://arstechnica.com/information- technology/2017/11/nasa-...](https://arstechnica.com/information- technology/2017/11/nasa-icebridge-flying-lab-aids-in-search-for-missing- argentine-navy-sub/?comments=1)

</comment><comment><USER10> Tyler Rogoway's article mentions the US Navy is on standby with their Submarine Rescue Diving Recompression System[1] in case their help is requested. But hopefully it's on the surface but disabled and will be located soon.

[0] [http://www.thedrive.com/the-war-zone/16195/frantic-search- un...](http://www.thedrive.com/the-war-zone/16195/frantic-search-underway-for- missing-argentine-submarine)

[1] [http://www.navy.mil/navydata/fact_display.asp?cid=4100&ct=4&...](http://www.navy.mil/navydata/fact_display.asp?cid=4100&ct=4&tid=400)

</comment><comment><USER11> Sort of a weird article, talking about the disappearance and the hunt and the worry without actually talking about what the boat is or what its crew does: this is a diesel-electric attack submarine, designed deliberately to evade detection and sink other ships with torpedoes.

They routinely operate without contact for days at a time, and have limited means of signaling a mayday situation. Pretty much everyone recognizes that when these things run into trouble, they may very well simply disappear.

So, it's a tragedy. But, not really an unforseen one.

<comment><USER12> ARA (Armada Argentina/Argentina Navy) San Juan. 1983 Diesel Electric, recently serviced. [https://en.m.wikipedia.org/wiki/ARA_San_Juan](https://en.m.wikipedia.org/wiki/ARA_San_Juan)

<comment><USER13> I read about that service somewhere, they basically cut the boat in half to replace the engines and then welded it back together.

<comment><USER14> >According to Minister of Defense Agustin Rossi, the MLU cost some 100 million Argentine Pesos (12.4 million dollars) and comprised more than 500,000 work hours in which the boat was cut in half and had its four MTU engines and batteries replaced. The MLU was under way at CINAR since August 2007. He blamed the delay on the lack of funds and qualified labor.

> Rossi called the re-delivery an important milestone for Argentina, as the > state had lost its ability to repair submarines following the previous > Domecq Garcia shipyards being disbanded.[1]

Distinct lack of details; though the article says crew of 37 when every current article about it missing states 44.

edit: The lack of maintenance facilities is worrying, though it sounds like the overhaul has created a grannies broom; there's not much of the original sub left.

[1] [http://en.mercopress.com/2014/06/19/argentine-navy- receives-...](http://en.mercopress.com/2014/06/19/argentine-navy-receives- refurbished-tr1700-class-submarine-ara-san-juan)

Linked from wikipedia: [https://en.wikipedia.org/wiki/ARA_San_Juan#cite_note-5](https://en.wikipedia.org/wiki/ARA_San_Juan#cite_note-5)

<comment><USER15> > _it sounds like the overhaul has created a grannies broom; there 's not much > of the original sub left._

I've heard of Theseus's Ship, and grandfather's axe - granny's broom is a new one to me.

<comment><USER16> I noticed, and enjoyed, that variation too.

A few of my software products have gone through multiple frameworks and rewrites, but from the user's point of view they appear to have remained one evolving entity. My phone/personal-digital-assistant also has kept its name for 21 years, but has gone through a series of reincarnations.

</comment></comment></comment></comment></comment></comment><comment><USER17> > _" Argentine authorities are scrambling to find a three-decade-old > submarine..."_

30 years doesn't seem that old for a submarine. A good proportion of the UK fleet were launched in the 80s.

What age does the US start decommissioning subs?

<comment><USER18> The Ohio-class submarines of the US Navy date back to 1981, and their replacement isn't due until 2029 (and probably won't happen until later than that).

The Taiwanese are still operating a submarine which was launched in 1944.

So yeah, a 30-year-old submarine is merely middle-aged. On the other hand, Argentinian maintenance standards are not exactly the envy of the world (cf [http://www.foxnews.com/world/2013/01/23/argentine- destroyer-...](http://www.foxnews.com/world/2013/01/23/argentine-destroyer- that-led-war-against-britain-sinks-symbol-decay-for-once.html) )

<comment><USER19> Argentina is an amazing place who level of screwed-upness is tragic.

<comment><USER20> Argentina has 2 distinct effects. The first is that after the dictatorship in the 70's, the military has been systematically defunded. Any politician that needs a buck, and they all do, will always put the military last. Its a front- pager for the government to buy a new military plane: it costs votes and money.

And second, we have a level of systematic corruption that has eroded many institutions, including the military. Noticeable so, the state of military aircraft is in shambles and many army people died because the funds for maintenance where stolen. A famous documentary by a former pilot details these issues.

</comment></comment></comment></comment><comment><USER21> These submarines are weapons of war, for defence and offence. It is interesting how rival countries are willing to help out in these situations.

If this submarine had got lost when the Falklands war was a hot war, would the British lend them a helicopter or two to help them look? Particularly if it was a day or two after the Argentine Air Force had taken out a ship or two of the Task Force.

'Here you go guys, if you need help with salvage...' would not have happened then or in the post-war aftermath. Instead the Royal Navy would have denied the Argentine armed forces access to the area and the depth charges would have been deployed, the submarine gone for good like the General Belgrano. The victory would be selling newspapers. Only a few left wing anti-war moaners would be grumbling.

But today obviously there is 'peace' and as much help as much as possible is coming from the British establishment with no hesitation.

If the North Koreans lost a submarine would other countries such as the UK/USA offer them help to find it, particularly if it could one day point missiles at the USA? Maybe there should be an on-going 'lost-submarine test' where world tensions and hostilities are gauged by how many countries participate in military search and rescue operations.

<comment><USER22> As Lord Palmerston said, "Nations have no permanent friends or allies, they only have permanent interests."

Argentina's politics are certainly... interesting... but there's no question that Argentina is a strategically important country for major powers to court. Major military powers have little to fear from the San Juan in a hypothetical conflict, but much to gain from friendly relations with Argentina.

<comment><USER23> Also, what a great chance to have a sanctioned hunt of an Argentinian sub/vessel.

Nothing breeds experience at hunting subs like going sub hunting -- and now several navies get to, in an area they know one exists, without it offending anyone.

</comment></comment></comment><comment><USER24> >But a storm pitching powerful winds and waves more than 6 meters (20 feet)

Isn't that normal? The Atlantic off south east Canada 5m (15 feet) waves are a normal everyday thing. The coast off Argentina seems like it would be similar in climate.

</comment><comment><USER25> _"It was not immediately clear what type of calls the vessel may have tried to make but submarines that are stricken underwater can float a location beacon known as an EPIRB to the surface that can then emit emergency signals via satellite."_

Makes me only _very_ slightly more optimistic w.r.t. the chances of finding the crew alive. Being military, their normal objectives would include "don't let anybody see you", so they wouldn't use such a device unless they were in truly dire trouble.

</comment><comment><USER26> > U.S. company specialized in satellite communications

Nice. Hoping Argentina and US can bring these sailors back safely.

</comment><comment><USER27> Seems like there's new information since this article: "Argentina says signals detected, likely from missing submarine" - [https://www.reuters.com/article/us-argentina- submarine/argen...](https://www.reuters.com/article/us-argentina- submarine/argentina-says-signals-detected-likely-from-missing-submarine- idUSKBN1DI0M8)

<comment><USER28> Thanks! Url changed from [https://www.washingtonpost.com/news/worldviews/wp/2017/11/18...](https://www.washingtonpost.com/news/worldviews/wp/2017/11/18/a-submarine- has-vanished-launching-a-frantic-search-for-44-people-on-board/).

</comment></comment><comment><USER29> Several 'failed satellite calls' have been detected (how?) attributed to missing military sub.

[https://twitter.com/BreakingDotUK/status/932041323816906753](https://twitter.com/BreakingDotUK/status/932041323816906753) quoting Reuters.

Fingers crossed!

<comment><USER30> As for the failed satellite calls, my guess would be that communication was initiated, but that all of the handshakes required to actually place a call were not completed successfully.

Typical cause: you are equipped with a gain antenna which requires stabilisation to point at the relevant patch of sky - and the stabilisation isn't working. You can aim for the general area and sometimes, you get close enough to start the connection process. (Or any other number of reasons - <USER2> above I have experienced myself. Luckily, we had the option to switch to a lower-gain antenna and connect anyway (at a higher rate.)

</comment></comment><comment><USER31> What a terrible headline, and the article isn't any better. "Argentine military submarine with crew of 44 lost at sea" is perfectly sufficient. Writing standards have really taken a dive since news went digital, which is the opposite of the world I'd hoped for when I was evangelizing the internet back in the 90s :-(

I'm not optimistic for the poor sailors. If a modern submarine is genuinely missing it's usually because it was on some sort of covert mission when it got into difficulties.

<comment><USER32> Even worse is the computer-generated "related" links that are inserted inline with the article. We're talking about peoples' lives and you're trying to bait me with a headline about cocaine and hookers? This is why human editors are necessary for journalism.

<comment><USER33> >This is why human editors are necessary for journalism.

What difference would a human editor make? There is an exorbitant amount of news people on social media trying to convince everyone that they are needed.

<comment><USER32> I would assume an editor would have chosen more tasteful articles to link to. Or at least something that bears more of a similarity to this story than just having the word "submarine" in the headline.

</comment></comment></comment></comment><comment><USER34> im sure they will surface when Argentina plays its first match in the upcoming World Cup

</comment><comment><USER35> They all timing ticking bomb, since most (all by now) are nuclear reactor propelled.

As we all know, if something can break, it will break eventually. Its only a matter of time when one of these creatures sink to the bottom and pressure will take care of the rest, causing world panic due to nuclear material getting released into the ocean.

<comment><USER36> Nine nuclear submarines have already sank:

[https://en.wikipedia.org/wiki/List_of_sunken_nuclear_submari...](https://en.wikipedia.org/wiki/List_of_sunken_nuclear_submarines)

There hasn't been any world panic. There's lots of reasons to dislike the war- machine. (I myself am a former nuclear naval officer turned conscientious objector/pacifist.) But FUD does not help the case against militarism.

<comment><USER37> _I myself am a former nuclear naval officer turned conscientious objector /pacifist._

This is tangential, but can I ask about some of your experiences or reasons for that? It sounds interesting.

Only curious. Feel free to shoot me an email if you'd like.

<comment><USER36> On my blog, I have a page about the whole process here: [https://izbicki.me/blog/my-co-discharge.html](https://izbicki.me/blog/my-co- discharge.html)

If you want something more condensed, here's a news article: [http://www.nytimes.com/2011/02/23/nyregion/23objector.html?p...](http://www.nytimes.com/2011/02/23/nyregion/23objector.html?pagewanted=all)

<comment><USER37> Your AK-47 to serving spoon project is interesting too: [https://izbicki.me/blog/turning-an-ak-47-into-a-serving- ladl...](https://izbicki.me/blog/turning-an-ak-47-into-a-serving-ladle.html)

<comment><USER36> Thanks :)

I have another rifle and 4 swords that I want to do something similar with as well. I don't think I could do a very good job with them though. (TBH, I'm a bit disappointed with how the ak-47/ladle turned out.) So I've been looking to find a good artist to donate them to.</comment></comment></comment></comment></comment></comment>


Ask HN: The HN karma paradox - <AUTHOR> Am I right about any of this?
It appears that a comment which makes a point that's already widely accepted, whether true or false, tends to get more upvotes than a comment which is more controversial - again, whether true or false. The controversial yet true comments are usually more interesting and valuable. (Maybe that applies even to false controversial comments.)
Fortunately, I think most people here care more about saying what they want to say than about getting more upvotes. So I'm not saying something needs to be fixed or that I have a much better idea. Still, I think it's a reason to be cautious about taking someone's karma score very seriously. Forgive me if I'm just saying things you already know. <comment><USER2> The problem is that a single upvote-downvote axis has to capture two different, sometimes orthogonal, judgments: (1) is this comment valuable or detrimental to the discussion?; and (2) do I agree or disagree with this comment?

This entanglement is unavoidable as long as there's only one score per comment, given the interface and established practice, at HN and similar sites.

It might work to have a second axis/score that's specifically agree/disagree. (This could take the form of left-agree and right-disagree arrows, perhaps on the right of the comment-meta-line.) Then a comment could be be wildly agreed- with without offering a karmic windfall to repetitions of obvious popular sentiments, or wildly disagreed-with without the current undercurrents of censorship (sinking/fading-out) and karmic punishment via disagreement- downvotes.

Personally, I would expect to find the comments with both net upvotes (valuable) and rightvotes (disagreement) to be most interesting -- because they capture challenging minority viewpoints, but well-presented.

<comment><USER3> It might be interesting for you to look at the rating system that's used on the site RSDN.ru (Russian Software Developer Network). The site has been around for quite some time and they've formulated a very balanced approach to rating.

On that site one has 7 buttons to rate a message: 1, 2, 3, '+', '-', '+1' and ':)'

1, 2 and 3 affect score (=karma) of the message and its author based on the level of the person who rates it (i.e. 2 from a 5th level person would add 5*2 = 10 etc)

'+' and '-' show that you agree/disagree with that comment, but do not affect the score.

'+1' adds 1 point to score independent of rater's level.

':)' shows that you find this comment funny.

I translated rules from this page <http://rsdn.ru/forum/Info.aspx?name=info.forum.rating> and as you may see, there are more rules that help to prevent excessive you-rate-me-I-rate-you behaviour, keep score up-to-date (your level depends only slightly on your all-times score but greatly depends on the marks that you've got during the last month) etc.

If people are interested, I can translate the rest of the rules.

<comment><USER4> Interested!

This has some of the same qualities as Slashdot, where you tag one of several reasons on your moderation.

EDIT: I just thought of a more user-directed mod/metamod system along the lines of Slashdot, but this way would be more Web 2.0. (As opposed to web 1.99a like Slashdot.)

Have a choice of pre-defined tags (about 10), each with a karma score attached to them. These tags would be long the lines of: "Funny" "Interesting" "Insightful" "Logical Fallacy" "Troll" Users could choose to either moderate a comment, which would be attaching 1 or 2 tags to a comment and thus altering the comment's visibility rating either-or meta-moderating, which would be voting on the fairness of moderation. So you could see what tags are attached to a comment and vote fair/unfair on each of them.

Now here's the rub: you get Karma by fairly moderating. (And lose it by unfairly moderating.) So while moderating changes a comment's visibility, only meta-moderating affects Karma.

Karma would be rewarded by the number of tags one could apply to a comment.

EDIT: More ideas. Users should be able to define their own tags, but only the admins would decide what point score should be attached to them!

</comment></comment></comment><comment><USER5> I think it's more that long, detailed, well-supported points tend to get more karma than simple one-liners. IIRC, PG posted once that there was a big correlation between comment length and score.

I've noticed much less of a correlation between popularity and score than I would've expected - certainly much less than at Reddit, where you can write a detailed page-long comment that completely demolishes the parent's argument, and then have it sit at -1 because voters on Reddit reflexively downvote articles that don't fit their preconceptions. Here, that same comment is often at +10 or more.

<comment><USER6> > IIRC, PG posted once that there was a big correlation between comment length > and score.

Yes, he wrote that. I wrote a small script to test that proposition. It does not hold up. If there is a correlation, it is only very weak.

You can have the source, if you wish. The script's written in Python.

<comment><USER7> I'm interested eru - could I see the script?

<comment><USER6> I have now sanitized the program. Anyone else wants to play with it?

PG, is it OK to download such massive amounts of items?

</comment></comment></comment></comment><comment><USER8> There are many interesting subtleties to voting and karma systems, such as the one we use here on HN. Another one is that a post that has a child that glorifies the parent _"Great insight, bla.bla."_ will inevitably be voted up. You can probably find more if you look a bit.

You assume humans are rational beings and vote accordingly. But they aren't, they are emotional beasts that are hard to control, and are full of strange biases and ideas about what is right and wrong.

See for instance this list of cognitive biases from wikipedia: <http://en.wikipedia.org/wiki/List_of_cognitive_biases> Your paradox is explained by one of the biases listed, I'll leave it to you to figure out which one ;-)

It's all about psychology.

<comment><AUTHOR> When did I assume humans are rational beings and vote accordingly? What I was getting at is that widely accepted points get lots of upvotes as people express their agreement, but more controversial points get more of their upvotes because of the comment's quality. For the controversial points, this is offset by downvotes from people expressing disagreement. See gojomo's comment for a possible solution.

I'm not saying any voting system can be perfect, but this particular problem is explained by the fact that multiple judgments are being captured by a single voting axis, as gojomo said.

<comment><USER8> Reading my parent comment I see that it may look a bit arrogant, sorry that wasn't intentional, I merely think the topic is interesting, and hope to add some value to the conversation :-)

I think that basically what's going on here is that a simplistic voting system, such as the one we use here, and also one that carries more parameters and dimensions will always just be a simplistic overlay on an extremely nuanced and varied set of psychological rules that humans use for evaluating their surroundings, thus making it hard to accurately have karma map onto a users insightfullness (in lack of a better word) I'm pretty sure I could get a lot of karma by using psychology tricks to make people upvote me, but it wouldn't be very interesting. Or ethical for that matter.

So I absolutely agree with you: Karma isn't a measure of a users insightfullness, there's probably a correlation but it's weakened by a lot of parameters, such as the ones you describe, age of the account, and lots of other factors.

And hey, Welcome to HN, hope you like it here :-)

<comment><AUTHOR> I agree; there's no perfect voting system. This is similar to what you said, but people getting lots of upvotes for saying something many others agree with probably means at least slightly fewer unpopular views are being posted.

Thanks for the welcome! I know the account is new but I've actually been here for a long time. :)

</comment></comment></comment></comment><comment><USER9> Soon you will realize the pointlessness of the score system (no matter how it's implemented), and from there it's a short distance to leaving it behind and getting down to business (whatever is business to you). Treat HN as a class which you need to graduate from and it will make a lot more sense.

<comment><AUTHOR> I'm not saying I expect the score system to be perfect and "fair". That would be impossible. But it isn't _pointless_ either, because it helps us sort the articles and comments. If it really were pointless, as you say, then even the single voting axis that exists today should be removed, right?

<comment><USER9> > it helps us sort the articles and comments.

Are you sure about that? I find it roughly as many good comments with low votes as I find with high votes. My most subjectively valuable comments remain at +2 whereas my smart-ass comments get upmodded uncomfortably high. Same with stories - half of the stories I find valuable are lingering at low scores.

Voting seems to be about social status, values and group identity, not about content quality. There are people who try to vote quality but I rarely see them rising above the normal voters.

I suggest you give it a try and take notes while reading both high and low rated stories/comments. Maybe you will come to different conclusions than I.

</comment></comment></comment><comment><USER10> Are we talking "karma for a single comment/post" or "karma for a user"? The reason I ask is that I've been using HN since close to the beginning and never once have I looked at a user's karma score. User karma has no meaning to me, good or bad. Post/comment karma matters in the sorting and what appears on the front page so, to me, it's the only thing that I care about.

So is your discussion more about user or post/comment karma? I suspect the latter.

<comment><AUTHOR> I guess I had both in mind. The post/comment karma for the reasons you mentioned, but also user karma - not just because people look at a user's karma score, but because it's used to determine other things. If it's used for even more purposes in the future (vote weighting, for example) its importance will only increase.

</comment></comment><comment><USER11> HN and most karma-based forums follow the bandwagon effect. The exception is probably slashdot, due to it's different way of power assignment and levels of voting

</comment><comment><USER12> What kind of point is widely accepted and false?

<comment><USER6> For example (but that's kind of a meta-point): If you select any skill (say driving) and ask a sample of people in which quantile they place themself, you are very unlikely to get a uniform distribution. (Like: "90% of people think themself above median drivers.")

<comment><USER5> But they're often _right_. Most people don't think themselves above-median drivers, they think themselves above-average (mean) drivers, i.e. if you take all the car accidents and divide by the number of drivers, they've been involved in fewer than that number. And they'd probably be right: the median number of car accidents is significantly lower than the mean, because a small number of bad drivers account for a large number of car accidents. Not everything is uniformly distributed - in fact, most things aren't.

<comment><USER6> I know that most things are strangely distributed. Even the normal distribution is far from uniform. So I was carefully phrasing my comments in terms of quantiles. Quantiles are evenly distributed by definition.

People think themself "better than the typical guy" i.e. above median.</comment></comment></comment></comment>


Is time a side effect of universal expansion? - <AUTHOR> http://mikemainguy.blogspot.com/2011/01/is-time-side-effect-of-universal.html

<comment><USER2> This is the stupidest thing I've ever read. He didn't even back up his argument.

</comment><comment><USER3> Show me the maths.</comment>


The Long-Ignored Reptile Rewriting the Prologue to the Dinosaur Story - <AUTHOR> https://www.theatlantic.com/science/archive/2017/04/teleocrater-dinosaurs-aphanosaurs-crocodiles/522489/?single_page=true <comment><USER2> Interesting stuff!

I'm more interested in the pseudo-suchian angle though at the moment. People seem to think of crocs a lot like sharks - at some point, many millions of years ago, a croc popped into existence and they have stayed much the same ever since. We also have a lot of news about dinosaurs and their seagoing or aerial relatives.

But the Crocs are fascinating. Some were just plain huge, like sarcosuchus, but there was masses of variety. They exhibited all sorts of convergent- evolutionary forms.

There were dog-sized crocs with long legs, bipedal crocs, there were 5m long sea-crocs with tail-flukes that filled the same niches as icthyosaurs or dolphins... almost all of them are total nightmare-fuel.

I want to know more about these!</comment>


Directed Energy Planetary Defense and Relativistic Probes - <AUTHOR> http://www.deepspace.ucsb.edu/projects/directed-energy-planetary-defense <comment><USER2> Happened to catch rockstar astrophysicist Neil deGrasse Tyson on Charlie Rose the other night and the subject of asteroid deflection came up. For small candidates, vaporization would be ideal. But for larger ones, any attempt at destroying them may have unwanted consequences. Debris fields, partial cleaving, etc. Sending a team of human miners with demolition expertise is not in the cards. So the current vogue in asteroid deflection would be to send something heavy to intercept the asteroid and deflect it a degree or two using only gravitational pull! A very clean and elegant solution that would no doubt make a great simulation or video game ;)

Mission Concepts and Operations for Asteroid Mitigation Involving Multiple Gravity Tractors

[http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201...](http://www.ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120013195.pdf)

<comment><USER3> The point isn't the vaporize them, it's to nudge them ever so slightly.

Consider a comet- you fire one or more lasers to a specific spot on the comet, causing heat. The heat causes the water to expand, and shoot off from the comet. Does this destroy the comet? Certainly not much of it. But as that water vapor shoots away from it, Newtons Third Law comes into play and the comet, ever so slightly, is pushed in the opposite direction.

You may rightfully say that this would be a very minuscule push, so what good will it do? Well, if you play Kerbal Space Program you'll quickly learn that tiny nudges can have huge effects in the long-run, especially on big orbits. Add a few mm/s to the velocity of a comet two years ahead of time, and it can make the difference between that comet hitting a planet, or not. It can mean the comet is ever so slightly closer to Jupiter, causing it to be pulled by its gravity just a bit more.

<comment><USER4> For the "larger ones" that fitzwatermellow was mentioning, the problem is that your mental model of a big rock starts breaking down. You'd be closer to think "big gravel pile sort of iced together, sort of held together by local gravity because there's nothing else pulling them apart". You shoot a little pulse at the gravel pile and break a piece off and it may simply fly out into space, taking almost all the momentum with it and not affecting the bigger body at all. You apply a big force and you might just send rocks _through_ the pile, with, again, the rocks going through taking most of the momentum you applied with them. (Same for landing a booster on it... there may be nowhere you can boost where the booster doesn't just drill right through and come out the other side.) Hit it harder and it may simply spread out.

The advantage of the gravity towing approach is that gravity affects the entire pile equally; it doesn't matter how tenuously the whole thing is held together. This approach could literally deflect a mountain-sized ball of pure sandbox-grade sand, completely and correctly. That's not something a lot of other approaches can say. It's only downside is that it's miserably slow, so you have to call the problem years in advance.

<comment><USER5> The problem with gravity pull is you first need to mach orbits which takes a long time or a lot of delta V. From an energy and complexity perspective your best bet is to impact with a large low mass object like foam or lots of tiny objects like a cloud of sand. The advantage being just about any orbit that gets you there works and high relative velocity's are good. The problem is it's easy to miss.

A solar sail is a solid candidate as you get a large low mass object and 'free' delta V at the same time.

PS: Due to risk of malfunction you likely want to send several ships anyway, while the miss chance is an issue, the cheaper direct approach lets you take more chances.

</comment></comment></comment></comment><comment><USER6> can this be weaponised to direct asteroids to a particular place on earth? just asking for a friend.

<comment><USER7> My guess is no. Reason: steering towards is a smaller target than steering away. If you can only point a laser from over here, it's hard to steer an asteroid any way except "thataway" (normal to the most visible surface).

<comment><USER8> unless the asteroid was closer to the sun than the earth, then you could push it so it hit earth 6 months from when you pushed it.

</comment></comment></comment><comment><USER9> What is our next move when it shoots back?

<comment><USER10> LOL!

</comment></comment><comment><USER7> Welp, it's officially the future once we have planetary defense laser bases.

</comment><comment><USER11> > DE-STAR or Directed Energy System for Targeting of Asteroids and exploRation

Ugh! "exploRation"?

</comment><comment><USER12> Naming it DEath-STAR is probably not the best way to build public support.

<comment><USER13> Have you _met_ geeks?

> sufficient warning

Well, yes, quite. Wouldn't we be better off making sure we can reliably find them first?

<comment><USER14> > Wouldn't we be better off making sure we can reliably find them first?

People are already are working on that. For example, there's the NEOWISE project[0], which used the Wide-field Infrared Survey Explorer to look for potentially dangerous astroids. And there is a ongoing effort for a new space mission, NEOCAM[1], specifically designed to do this same thing and find more objects.

[0] [http://neo.jpl.nasa.gov/programs/neowise.html](http://neo.jpl.nasa.gov/programs/neowise.html)

[1] [https://en.wikipedia.org/wiki/Near- Earth_Object_Camera](https://en.wikipedia.org/wiki/Near-Earth_Object_Camera)

</comment></comment></comment><comment><USER15> has anyone checked out the relativistic probes claim? what potential speeds are we talking about? and, i presume, there are no brakes? :D

</comment><comment><USER16> Trying to force asteroids away are we?</comment>


HTC to launch 'at least' three Google phones this year - <AUTHOR> http://www.infoworld.com/article/09/03/17/HTC_to_launch_at_least_three_Google_phones_this_year_1.html

<comment><USER2> More motivation for android based apps.</comment>


Show HN: HitchMe helps your texting game. - <AUTHOR> http://www.hitchme.co?website_code=hn&headline_code=1

<comment><USER2> The link at the bottom right of the page goes to hitchme.com, which doesn't work.</comment>


Samsung triumphs over Apple in Japan patent case - <AUTHOR> http://www.reuters.com/article/2012/08/31/us-apple-samsung-japan-idUSBRE87U05R20120831

<comment><USER2> Discussion of story from a different source:

<http://news.ycombinator.com/item?id=4458635></comment>


Show HN: Best way to clean your development environment - <AUTHOR> http://blog.tree.st/post/47364130523/disposable-baby-towels-best-tool-to-clean-your

<comment><USER2> Great tip, but I thought it was going to be how to identify and remove all the digital cruft in your environment. Tools and packages that were tried, abandoned and forgotten.

Anyone have tips like that?

My method: I occasionally do a scorched-earth OS reinstall, and install _very_ few packages and tools on the new installation. When I hit the speedbump of reaching for something naturally, I install it and move on.

It's kind of like a policy of throwing boxes out if you haven't touched them since your last move.

Anyone do anything different? Something more ongoing and less drastic?

</comment><comment><USER3> Nice trick :) I have already tried before, and I can confirm this. It's a great way to clean computer.</comment>


Ask HN: Who wants a product built in 48 hours? - <AUTHOR> I have a team headed to the TechCrunch Disrupt Hackathon this weekend.
What are some ideas that you think could be built over a weekend?
If you'd like to have an MVP built as part of this hackathon I'd love to help you out.
 Feel free to comment here or email at firstname.lastname@example.com
Could be a great way to get some press and to get something off the ground quickly. <comment><USER2> I'll also be going and looking for some chatbot ideas</comment>


Can anyone make money on the moon? - <AUTHOR> https://www.nytimes.com/2017/11/26/science/moon-express-outer-space-treaty.html?hp= <comment><USER4> Funny, I was just listening to a podcast where Andy Weir (author of The Martian) was interviewed about his new book, regarding a potential city on the moon.

To justify a book about that Weir had to think of an economic reason why there would be a city on the moon, because cities need economic rationales. He theorized that the price of space travel had been driven down enough that it could support a tourist economy, so the economics of a Moon city could be modeled on Caribbean tourist cities. Conveniently, 85% of the moon rocks are anorthite- which smelts into aluminum, oxygen, and silicon among other things. All of which would be very helpful for building a moon city.

Weir didn't have much to say about international treaties mentioned in this NYT article. But a key connection between the article and how he ask and answers the question is that they both seem to regard a budding space tourism industry as a foundational next step.

<comment><USER5> He's actually written "a 3,000-word (and spoiler-free) treatise laying out the economics behind his fictional moon city" available on business insider [1]

edit: I read this last week and 30 minutes later signed up to audiable to get it as my free book (ebook reader broke, amazon delivery too slow). It's an enjoyable book, but i wouldn't go into it expecting another Martian - it's fluffier.

Apart from that, if I couldn't afford the $70k holiday cost, then I'd probably have to get a temp job working up there for a bit - though the economics of migrating between aren't discussed.

[1] [http://uk.businessinsider.com/andy-weir-artemis-moon-city- ec...](http://uk.businessinsider.com/andy-weir-artemis-moon-city-economics- the-martian-2017-11)

<comment><USER6> One thing I'd worry about working on the noon would be finding myself in the sort of indentured servitude many cruise line workers and domestic helpers find themselves across the world.

I bet you won't be making $20/hour on the moon, if certain people have their way.

<comment><USER7> Asimov was really good for questions like this. I bet somewhere out there he wrote about why people would go to such places.

-edit- He even wrote a book titled "space colonies". First I've heard of it.

</comment></comment></comment></comment><comment><USER8> Highly recommend Isaac Arthur's well-researched video on industrializing the Moon: [https://www.youtube.com/watch?v=bGcvv3683Os](https://www.youtube.com/watch?v=bGcvv3683Os)

Separately, if nobody knows how to say yes, can't Moon Express just launch first and ask permission later? Or launch from a different country? I doubt the USSR is going to rise from the dead to enforce the treaty…

</comment><comment><USER9> Guys, nobody is going to make any money on the moon anytime soon. Or by mining asteroids, either, although that argument is more interesting, since (some) asteroids contain relatively pure rare elements. The moon, by contrast, is mostly just sand.

With current technology, it costs — round ballpark figures — about $25,000 PER KILOGRAM to launch mass into geosynchronous orbit, the highest orbit for which there is any current commercial launch market. If SpaceX really gets going, which it might, that number will come down. But it won't come exponentially down. It might get cut in half. But it's still going to be really really expensive to get aything to the moon, including the infrastucture and propellant that you would need in order to get things back from the moon. Put another way, that's about $800 an ounce at current prices, and $400 an ounce in the optimistic ten year scenario. Bricks launched into space are literally as expensive as gold bars.

And that's just launch cost. It isn't the cost of building the thing you're launching. Of course, the non-recurring engineering, fabrication, and test costs vary dramatically depending on the complexity of the spacecraft being built, but again, in very general terms, a geosynchronous communications satellite, which is the single spacecraft type that most closely resembles a commodity, as they are built on an assembly line, with relatively little non- recurring engineering and standardized designs and parts, those cost about $300 million each.

For a grand total cost, of building and launching a plain vanilla geo commsat, of half a billion dollars. And then you have to operate the thing. Any spacecraft mission of significant complexity - the complexity associated with manned spaceflight or planetary mining - is going to require round the clock teams of hundreds of engineers. So you're talking billions more dollars per year to operate.

If you're thinking of launching a man-rated lunar spacecraft, which you'd need for lunar tourism, multiply that by about thirty and you'd be at the low end of a decent estimate. A lunar prospector capable of returning samples - <USER2> samples, not bulk materials - is going to be in the low billions, plus billions more to run. A full on linar mining infrastructure is, again, tens of billions. At least. Probably hundreds of billions.

There is just nothing on the moon that's worth that much. In particular, there's nothing there that wouldn't be orders of magnitude less expensive - and much less risky, which is important from an investor perspective - <USER3> simply mine or manufacture on earth. You can dig a lot of mines for ten billion dollars.

<comment><USER10> There are many questions to this line of thinking. Technology marches ahead, and cumulative advancements are large even in comparison to early 1990, when NASA conducted studies have shown possibility for manned return to the Moon for about a billion dollars. Similarly, goals to go there now include space tourism - something not heard of even in late 1990 - or mining the Moon water, which we know more about today than when Clementine flew. Even such a boring thing as oxygen can be marketable after offering it in quantity on a convenient orbit for many customers to take.

When SpaceX demonstrated the expenses which it took to develop and fly Falcon-1 with supporting infrastructure, they beat the existing cost models by about a factor of four. Similarly here reaching the Moon can turn out easier than thought, and reasons to go there could become better than used to believe, as soon as some favorable conditions, like in 2002 when SpaceX was born, will be met.

<comment><USER9> Right, which is why the asteroid mining discussion is interesting — there are minerals in asteroids that have significant value, and if you could get the cost of access to space low enough, it might make economic sense to go get them. I'm skeptical that the economics of asteroid mining are going to close in the next fifty years, but there is at least a coherent argument for it.

But the moon is just a big rock. As far as we know, there's nothing there with any intrinsic value - the only economic value of the moon is that it's out of earth's gravity well. So if you had a sufficiently robust asteroid mining operation, or something, then basing it or staging it on the moon might make some sense. But the moon would only have secondary value in that scenario, and you have to postulate some space resource with really high primary value in order to justify being on the moon.

</comment></comment></comment><comment><USER11> Surely the easiest way to make money on the Moon is by threatening kinetic bombardment of Earth?

<comment><USER12> Seems very unlikely that for the foreseeable future, any Moon->Earth threat of kinetic bombardment could stand against an Earth->Moon threat of nukes and cutting off supplies. There is a fundamental asymmetry in that rendering Earth completely uninhabitable to humans would almost amount to terraforming a planet, whereas a Moon colony is rendered uninhabitable by, among other approaches, making a small number of strategically-placed holes in buildings.

<comment><USER13> I saw Dr Strangelove, certainly anyone who plans to (seriously) threaten the Earth with moon-launched WMDs would include some kind of dead man's switch in their plan.

What I think is this: so the UN (of Earth) acquiesce to your demand for a trillion dollars and mining rights to Ganymede. What next? It's not like you can go back to Earth and enjoy your new wealth.

</comment></comment></comment><comment><USER14> Various moon benefits:

\- Relatively close and accessible (as opposed to the other planets)

\- Seemingly stable platform to build, other wise we continue to rocket everything up from earth.

\- Raw Materials - stuff to build more space vehicles, structures, etc.

\- Lack of air - May help foster newer/cheaper materials and other processing

\- Low Gravity - Also may factor into developing new materials and bigger objects.

\- Lack of thick atmosphere - for astronomy, earth visualization.

\- for data centers - potentially better cooling, or energy (solar) less susceptible to intrusion, security, etc. Lack of air might be a plus too.

<comment><USER15> To add upon your comment, the moon could also act as an interplanetary shipyard. With the low gravity and stablity, as well as proximity to earth for raw materials and man power. Assuming it isn't completely automated.

Iirc, Isaac Arthur (I know him as a sci-fi YouTuber) has done numerous videos on how we could become an interplanetary/interstellar species. One of those videos covered the use of the moon to those ends.

<comment><USER7> I thought the moon had been ruled out due to lack of resources to compensate for the gravity well.

<comment><USER16> The amount of fuel it takes to get to Mars and the Moon is almost the same but the Moon has a bunch of aluminum and oxygen relatively easily obtainable. These two things can react energetically and be used in a hybrid rocket which could be used to shuttle stuff from the Moon to Earth. The stuff exists we just have to use it.

<comment><USER7> Sounds like the exports would be transportation related. Wonder if solar or nuclear would be more viable.

</comment></comment></comment></comment></comment><comment><USER17> Many people seem to be dramatically overestimating our knowledge of the moon's composition. When did we definitively proven there was substantial amounts of water on the moon? Most would probably think the answer would be the 60s or the 70s. In reality the answer is 2009 [1].

And similarly China's recent landing on the moon has reshaped our understanding of the moon as it turns out the geography of the area in which they landed was substantially different than that on which the US/USSR landed in the 60s/70s. [2] That discovery came in 2014!

The point I'm getting at here is that it's always wise to keep our ignorance in mind. Deep penetrating radar and other technologies can provide substantial information, but it's still limited. Our lack of knowledge is an ongoing and major constraint. And the interesting thing is that the more we learn, the more desirable the moon seems to become.

And of course it also goes the other way. The best people making the best decisions can come to decisions that later seem less than correct. The most recent example there being the discovery that the colored streaks on Mars being briney water -- it turns out it may indeed just be sand after all.

[1] - [https://www.space.com/7328-official-water- moon.html](https://www.space.com/7328-official-water-moon.html)

[2] - [https://phys.org/news/2015-03-china-yutu-lunar-rover- moon.ht...](https://phys.org/news/2015-03-china-yutu-lunar-rover-moon.html)

</comment><comment><USER18> There's no carbon on the moon. Unless you can harvest large numbers of comets, habitation at scale is impossible.

<comment><USER19> Stupid question. Is carbon only mandatory if you want long term sustainable agriculture? Or is it necessary for something else?

<comment><USER20> Presumably you'd CO2 to feed plants, so the plants could produce oxygen for breathing purposes. You'd also need carbon to create organic (aka carbon based) food. At a minimum, carbon will part of any system that includes people. A sustainable system would need some way to recycle carbon.

<comment><USER21> All the carbon on the moon would absolutely be recycled, much like it is on Earth.

So even if you have to ship all of it there, it's only a one time cost.

</comment></comment></comment></comment><comment><USER22> The potential I see on the moon is:

\- having a base to store things for later use.

\- a space elevator on the moon should be simpler than one on earth.

\- water could be extracted from the moon and shipped to earth orbit.

\- more convenient extra vehicular activities.

</comment><comment><USER23> Some ways to make money on the moon.

1\. Oxigen factories for Mars shuttles. Although Musk's vision for Mars makes sense as it is, it becomes much more economical if you add oxygen production on the Moon. You can manufacture the oxygen locally on Mars (via the Sebatier process), but you need some factories to do that. It's going to be much cheaper to build much larger factories on the Moon, and ship the oxygen on Low Mars Orbit. There are lots of numbers you can look at, but here's a quick comparison. The BFR second stage, planned to weigh 2100T, will be able to deliver about 170T of payload to the surface of Mars and about 980T to the surface of the Moon (almost 6 times as much). It's going to take much fewer trips to build a factory on the Moon, plus, if anything breaks, you can ship a replacement in days, rather than months or years.

2\. Build solar panels on the Moon and ship them to Mars. In a few decades it will be cost competitive with building and shipping from Earth. Compared to building locally on Mars, it will probably always be cheaper.

3\. Build nuclear rockets (not missiles) [1]. It's unlikely we will have the appetite to launch such rockets from the Earth in the next 50 years or so, due to the risk of breakup during launch. On the Moon however, everything above ground is continuously exposed to massive radiation (mainly from the Sun), so a nuclear fallout will not change things too much.

If we ever want to do true deep space exploration, we need to move beyond chemical rockets. The Moon can help us get there.

[1] [https://en.wikipedia.org/wiki/Nuclear_thermal_rocket](https://en.wikipedia.org/wiki/Nuclear_thermal_rocket)

</comment><comment><USER24> I would think they would have their very own trade system if it isn't just a government funded experiment. Although I predict it would take a long time to establish a trade system and one that involves cash or credits

</comment><comment><USER25> Helium-3 (He3) is gas that has the potential to be used as a fuel in future nuclear fusion power plants. There is very little helium-3 available on the Earth. However, there are thought to be significant supplies on the Moon. Several governments have subsequently signalled their intention to go to the Moon to mine helium-3 as a fuel supply.

[http://www.explainingthefuture.com/helium3.html](http://www.explainingthefuture.com/helium3.html)

<comment><USER26> Mining the Moon to fuel fusion reactors with helium 3 is a cockamamie scheme for the foreseeable future. First, nobody has made a fusion reactor that produces net electricity even with the _least_ demanding fuel (deuterium- tritium). He-3-deuterium fusion requires significantly higher temperatures. Second, if He-3 _did_ become a valuable fuel, it can be manufactured here on Earth by irradiating lithium with neutrons, just like tritium; it's what tritium decays to. Finally, the lunar regolith concentrations of He-3 are at the _parts per billion_ level.

The latest He-3 prices I can find are around $2000/liter (~$15,000 per gram). At 18.354 MeV per D-He3 fusion and 40% thermal-to-electrical efficiency (generously), one gram of He-3 yields

1/3 * 6.02 * 10^23 * 18.354 * 0.4 * 4.4505 * 10^-20 = 65565

kilowatt hours of electricity. To produce 1 kilowatt hour of electricity, the helium 3 cost _alone_ would be 23 cents. For comparison, the average _retail price, delivered_ for electricity in the US is below 11 cents per kWh. Even if you had a working fusion reactor all ready to turn He-3 to electricity, He-3 would need to be an order of magnitude cheaper to have a prayer of He-3 fusion competing economically against other electricity sources. And if He-3 is an order of magnitude cheaper that makes it correspondingly harder to turn a profit mining the Moon for it.

Helium 3 lunar mining is not an investment opportunity. It's the end product of motivated reasoning, where the motivation is "I want humans to be doing more things in space."

<comment><USER27> There's a fundamental reason why lunar He3 isn't worth mining: if you can get net power from D-He3, you can also get net power from the easier D-D reaction, and the output of that reaction is half He3 and half tritium. If your D-D reactor is profitable then the He3 is effectively free.

Ycombinator-funded fusion startup Helion is working on a hybrid D-D/D-He3 reactor, and says the combined reaction would release only 6% of its energy as neutron radiation (compared to 80% with D-T).

</comment></comment></comment><comment><USER28> sure there is plenty of money in tourism

<comment><USER29> Consider just the launch cost of an Apollo type mission. S-IVB is 110 Mg, the Command/Service module was 30 Mg, and the lunar module was 16 Mg. That gives us about 150 metric tonnes as a reasonable estimate of the payload to LEO needed for a lunar trip.

Right now, you're looking at about $340M (at $2200/kg) on two falcon heavies to boost that.

If we handwave R&D and engineering costs, you're still looking at around $170M per person on the moon.

Of the not-so-many people who can afford that, how many people do you think will actually do so?

<comment><USER30> They [0] ?

[0] [https://en.wikipedia.org/wiki/The_World%27s_Billionaires](https://en.wikipedia.org/wiki/The_World%27s_Billionaires)

</comment></comment></comment><comment><USER31> I always thought that a good way to spawn a space race would be to let the first human representative of a country who successfully lands there and plants a flag gets the planet.

As a species, we should agree to these terms, because expansion of our species is more important than anything.

<comment><USER32> Getting the planet/continent/island is easy. _Keeping_ it from all the other humans who come planting their own flags...now that's the hard part, where the weapons come in.

</comment></comment><comment><USER33> I'd repudiate the Outer Space Treaty wholesale. Of course, the New York Times would never mention that as a possibility.

<comment><USER34> The article explicitly mentions the possibility: "Officials at Moon Express and Planetary Resources say they do not want unfettered freedom in space, nor do they seek withdrawal from the Outer Space Treaty."

</comment></comment><comment><USER35> Could we not build some kind of massive solar farm on the moon? Then beam down all that power to earth.

(Just thinking out loud here)

<comment><USER36> It's a lot cheaper to build huge solar farms in deserts. Probably a couple of orders of magnitude cheaper.

<comment><USER37> That depends on how cheap space flight is in the future, in the past (say 1800) the thought that it would be substantially cheaper to manufacture something in China and ship it across the pacific ocean than it would be to manufacture it locally was not only laughable but utterly insane.

<comment><USER38> _That depends on how cheap space flight is in the future_

Your argument works better to support the statement, "That depends on how cheap space manufacturing is in the future." We can fairly easily procure massive amounts of aluminum and silicon on the Moon. If we can invent industrial processes and perfect tele-operation, then we could create massive solar farms on the Moon. However, it might be even better to launch the material from the lunar surface with electromagnetic drivers and construct the solar farms in orbits, where they would receive sunlight 100% of the time.

Japan's space agency has already conducted tele-operation tests in conditions of massive lag. It turns out that highly motivated people can tele-operate manipulators even with 1 second of lag. This puts the Moon within reach of such tele-operation.

</comment></comment></comment></comment><comment><USER39> Not yet. Wait for few more years and we will get our answer!

</comment><comment><USER40> H3

<comment><USER10> You've surely meant He3?

</comment></comment><comment><USER41> there is a dispictable me joke in here some where, the villain in that movie tries to make a great deal of money from the moon.

</comment><comment><USER42> Say goodbye to Diets and feel slim again eating all that you want at the same time!. Yup, I $€€ potential here.

Or maybe we could eliminate enough matter from the moon to make tides less strong and compensate the effect of the climatic change.

<comment><USER37> If we mess with the tides, climate change will be the least of our worries, we'd be facing total ecosystem collapse. Many species have life cycles that are very closely tied to the effects of the tides, messing with the strengths of those effects could be catastrophic to life on the planet.

<comment><USER42> Then if we colonise and make massive cities in the moon or if we mine extensively the moon for minerals and move them to the earth, aren't we changing (slightly) the mass of the moon?

This lead to an interesting question. If we keep adding or removing enough stuff for enough time, at some point we could trigger artificially an effect on tides. We should have a wide safety limit (taking in mind than the moon mass is much bigger than lunokjod2 mass for example, and also any asteroid is also much more massive than human stuff left in the moon), but there is a limit in theory. This could change at long term if we colonise seriously the moon. I wonder if somebody has calculated this coeficient yet. If not, you can call it the "loony valdes" limit, XD XD ;-).

About if anyone can make money on the moon, I bet that just recovering lunokjod-2 and bringing it to the earth (or fixing it, if still functional) should provide some money for the rescuers. Is the biggest known concentration of rich metals in a small spot of the moon surface and also the easiest to find and mine. This stuff must be expensive.

</comment></comment></comment><comment><USER43> I haven't looked at the article but I'm confident there is no profit to be made going to the moon.

<comment><USER44> we're glad you're confident but let's agree your comment isn't bringing much value to the convo

<comment><USER43> Okay lets see what the article actually says... "The moon, peppered with the impacts of asteroids over the eons, should also possess dollops of platinum and other precious metals. Helium-3, embedded in the lunar crust by the solar wind, could be fuel for future fusion power plants."

Unconfirmed dollops of precious metals (no mention of how to extract this) and fuel for a type of reactor that does not exist. All this at the most inaccessible place humans have ever been! Sounds lucrative.</comment></comment></comment>


Over half the firmwares uploaded to TCSL Armor have invalid certificates - <AUTHOR> https://tcsltesting.blogspot.com/2018/09/50-of-firmware-certs-are-expired.html <comment><USER2> Does this mean that if the cert expired, the hardware driven by the firmware should become useless unless the vendor adds a new cert?

<comment><USER3> Ideally, a chain of ongoing trust signs that a validation occurred before the cert expired. For example, the owner of a laptop could sign an initial validation and continue to trust the firmware was authentic and not backdated after perhaps the original certificate expired and then its key length gradually became factorable.

It is rather hard to handle code signing and backdating problems purely in software without either removing the benefit of expiration or requiring someone to go sign for the legitimacy of a lot of things they only sort of trust. This has been comming up a lot with git signing and key lifetimes too.

<comment><USER2> I don't understand that. If the owner of the laptop approve by an initial validation, then he could as well approve by accepting unsigned binaries? Having a cert which cannot be validated seems more or less the same to me as having no cert. All the usual caveats apply: vendor loses signing key after expiration, etc... Vetting which firmware is safe is exactly the responsibility the end user didn't want to have to begin with.

And if the owner doesn't get that power from whoever designs the OS, it makes a reinstall of the device impossible.

The only way out I see apart from never expiring the certs is having a central third party vet the signature ('Yes, this binary with this signature was in our storage before the expiry.') A microsoft update or debian firmware repository could assume that role. But then you are depending on a third party for hardware you own yourself, and if they would rather have you upgrade, you're toast.

<comment><USER4> Where the certificate is just bogus, like it says "Test" or "Do not use" on it, and that's not a joke (TPPI which stands for "Test Pack Please Ignore" genuinely is one of the more famous Minecraft modpacks so, you know...) then you're correct that all bets are off.

But, where certificates expire the whole _point_ of a code signing or document signing system that makes it different from the Web PKI (certificates for stuff that speaks TLS) is that it makes use of Time Stamping, ala RFC 3161.

The Time Stamping services don't know anything about anything, except they promise to make signed documents saying they saw a particular bit-string (a hash) at a specific moment in time. Timestamps.

And it turns out that this (if you trust any Time Stamping service to know what the time is and not be corrupt) is enough to bootstrap a completely acceptable code signing system where even though the certificate expired in say, January 2017 you can trust that it was valid in March 2015 when its keys were used to sign some code, so therefore the code is still good.

The Certificate Transparency system does a lot MORE than this, but that only makes sense when we want transparency, proprietary vendors mostly do NOT want transparency.

<comment><USER2> I start to see how this works. There is a third party, but they intervene at signing time and not at validation time.

In detail: You create a hash of your executable and send it to the third party, the TSS. They sign the hash, and never even need to see the actual executable. As long as the end user trusts the third party's cert, the TSS can guarantee the executable existed in its current shape on the date you claim it existed. A kind of notary service.

For who wants to know more: Here is a Java article detailling how this works for Java, and what happens if the TSS cert itself expires

[https://blogs.oracle.com/java-platform-group/signed-code- nee...](https://blogs.oracle.com/java-platform-group/signed-code-needs-to-be- re- signed?source=:em:nw:mt::RC_WWMK180514P00061:SEV100743665&elq_mid=122882&sh=19261382112291426131527042&cmid=WWMK180514P00061)

And wikipedia is interesting too:

[https://en.wikipedia.org/wiki/Trusted_timestamping](https://en.wikipedia.org/wiki/Trusted_timestamping)

</comment></comment></comment></comment></comment><comment><USER5> Interesting, I really hope results are caused by people testing weird stuff. But like the author says, and I too, would be worried if it is because of manufacturer neglect. And they should probably be outed.

I will contribute by uploading my firmware as instructed here [https://tcsltesting.blogspot.com/2018/08/instructions-on- how...](https://tcsltesting.blogspot.com/2018/08/instructions-on-how-to-dump- your.html?m=1)

</comment><comment><USER6> Kudos to this much needed community effort to shed more light on firmware integrity. Please upload your device firmware if you have the tools, [https://tcsltesting.blogspot.com/2018/08/whats-in-your- firmw...](https://tcsltesting.blogspot.com/2018/08/whats-in-your-firmware-and- why-should.html)

For more on firmware, open-source and boot integrity, see the talks and references at [https://www.platformsecuritysummit.com/2018/topic/boot/](https://www.platformsecuritysummit.com/2018/topic/boot/), especially _" Firmware is the new Software"_.

The first (?) conference on open-source firmware was held this week in Germany, [https://osfc.io](https://osfc.io).

</comment><comment><USER7> Good post. Would have liked to see the actual offenders in question.

</comment><comment><USER8> This is kinda what I would expect. If people can get away without valid certificates they will. Before Lets Encrypt I would find that every "intranet" site I used would have a cert expire every year. The people who run these are cheap fk's and use LE because they don't have to pay.

</comment><comment><USER9> I'm absolutely going to start all future written communication with "So, anyway ..."! :)

</comment><comment><USER10> [removing noise due to misunderstanding]

<comment><USER11> It may be true that TLS x.509 PKI is broken in the context of embedded devices, sure. But that's not the problem being discussed here.

The first problem is that certs used to sign a lot of firmware seem to be test certs.

The second problem is that (unless the OP misunderstands firmware signing) a lot of the certs were expired _at the time the firmware was signed_.

All in all this just seems like something that should be enforced through a standards body. Like, to get FCC or customs approval, or some other checkmark that allows selling your product, show that all your software was signed properly.</comment></comment>


Building AGI Using Language Models - <AUTHOR> https://leogao.dev/2020/08/17/Building-AGI-Using-Language-Models/ <comment><USER2> I remain to be convinced that encoding statistical information about syntactical manipulation alone will somehow magically convert to semantic knowledge and agency if you just try really hard and do it a lot.

<comment><USER3> How much have you played with GPT3?

<comment><USER2> enough to know it's ELIZA on steroids. Neat party trick, and there's no there there.

<comment><USER4> I think that's overly dismissive of it. GPT-3 for me represents the very beginnings of breaking out of the paradigm of a specialized machine learning system for each task. GPT-3 is alternatively a (surprisingly good and consistent) machine translating system, a (disappointingly mediocre) calculator, a (very uneven with flashes of brilliance) chatbot, etc. All without special engineering to do any of those things. I can't think of any other system I have access to that does that.

Regardless of whether you think GPT-3 represents a track towards true AGI, this is a huge advance! Even OpenAI's API for it is astounding compared to other APIs. I can't think of any other API that amounts to "provide an English language description of your task" and returns an answer. Like I said, the results are still quite uneven, but the fact that it's not extraordinarily outlandish to provide such an API is absolutely mind-boggling to me.

I don't think I could have ever imagined such an API existing even just 5 years ago!

This is way way beyond even the same qualitative thing as ELIZA.

</comment></comment></comment></comment><comment><USER5> To me GPT-3 excitement is equivalent to when people get hyped about "defeating aging" after seeing some resveratrol trial or something.

Language is only part of it. And you can't get complete understanding without integrating spatial information. Take a look at Josh Tenenbaum's work for explanation of why.

</comment><comment><USER6> It talks about how you can go from a language model that simply generates text to an agent that is capable of performing actions in the real world

Essentially, the missing pieces in the picture come down to input and output modules. "How do you formulate any given problem into a form that a language model can answer?".

<comment><AUTHOR> I don't doubt the input and output modules will need some work, but in the grand scheme of things probably not that much. The big missing piece imo is just models with better world models—and it doesn't look like the scaling wars will stop anytime soon, nor does it look like size will stop helping, at least not anytime soon. ([https://www.gwern.net/newsletter/2020/05#baking-the- cake](https://www.gwern.net/newsletter/2020/05#baking-the-cake))

</comment></comment><comment><USER7> If the agent state is symbolic, that's cool and interesting, but isn't reality sub-symbolic?

</comment><comment><USER8> I don't completely follow this. Can anyone explain?

<comment><USER9> tl;dr Language models like GPT-3 include incorporate some model of the world. That's why they can generate plausible-sounding text. Future language models will be larger, more powerful, and have more complete models of the world. So we will be able to ask the language model questions, like 'what will happen if we do X?'. By compiling the answers to many such questions, we can figure out the best[0] thing to do.

[0] Assuming you have some utility function you can maximize.

<comment><AUTHOR> This is a great summary!</comment></comment></comment>


Show HN: Movie recommendation, Read plot before name - <AUTHOR> http://recommendmoviebyplot.com <comment><USER2> Very good idea. Usually the way I choose movies is that I (on IMDB) read the plot, then ratings, afterwards the category and finally eventually reviews/comments.

Any chance to add the other information to the list as well? It would be interesting to list the movies by categories as I tend to skip 'romance' :)

Also, I like the minimalist design of the website. I think it suits well the purpose.

If you want feedback from more people, you can try [https://usability.testing.exchange](https://usability.testing.exchange) (disclaimer: I am associated with it).</comment>


Uber CEO's memo on London ban: 'There is a high cost to a bad reputation' - <AUTHOR> https://www.recode.net/2017/9/22/16352700/uber-ceo-dara-khosrowshahi-memo-disappointed-london-decision-ban <comment><USER2> It took me a while to get Travis Kalanick's last name right (Klanick? Kalaniuk? Kalanik?), and now I gotta deal with 'Khosrowshahi'.</comment>


Use Dropdown Login Boxes for a Faster Login - <AUTHOR> http://uxmovement.com/design-articles/dropdown-login-boxes-for-faster-login <comment><USER2> Worst. idea. ever. I hate this on Twitter, it breaks the password manager and it is an additional click just to show a login. How is it so intrusive to have 2 fields on a page?

<comment><USER3> _How is it so intrusive to have 2 fields on a page?_

Depends on the design, goals and intended audience.

Form fields are harder to ignore than most page elements and have a sort of gravitational pull on the eyeballs, so you can easily imagine situations where it's better to avoid them. Like, say, on public marketing pages for first time visitors to a microblogging app that's way hard to explain to your average non-blogging Yahoo-using grandma in flyover country.

<comment><USER4> That makes sense, and says what I've felt/intuited (but never known for sure).

I typically put a username / password box on any pages I want people to be logged in for. Now, obviously, this includes pages that they must be logged in for, but those pages should enforce authentication more strictly; But what I really mean are the pages that don't 'require' authentication, but for any number of reasons, it is preferred.

Also, I've always believed that the 'two boxes on a page' approach draws them torwards the login, and acts more as a call to action than Twitter's dropdown approach.

As alabut says though, use where appropriate.

</comment></comment></comment><comment><USER5> Javascript, password managers & regression aside, the thought process behind the article makes sense. What sent up red flags is the only evidence for this UX is anecdotal: "twitter uses so it must be good."

When developing UX methods, you must test the fuck out of them. I wish the article had some numbers to back up their "we removed two boxes" illustrations.

</comment><comment><USER6> from day-one (Oct 2008), I designed the login form on <http://costpad.com> to be

      - embedded in every page so the user logs in whenever he/she wants
      - always shown so a single click starts the process
      - keyboard-friendly by using Tab to navigate to the input boxes
      - Javascript-less friendly, so to be able to log in without JS
       and not having to "bypass" my beloved NoScript
      - big-styled (as the rest of the webapp) so to be tablet/finger friendly.

Yes, this implementation occupies quite a lot of space up there, but I think the trade-off is fine.

The popup/dropdown login form is certainly cool and space-saving, but I couldn't come up with an implementation that satisfies me...

</comment><comment><USER7> I've only seen dropdown login boxes on non-SSL pages. Which means I never use them.

<comment><USER8> This was the point I wanted to bring up; if you have your login form on a non- ssl page, it's possible for a man-in-the-middle attack to replace the "action" on the form and send your login credentials anywhere they want. To prevent this with the drop-down login, you have to make your homepage SSL, which has other drawbacks.

</comment></comment><comment><USER9> How does popping up a new set of elements but merely on the same page entirely remove the "visual processing" step? You still have to look and work out how the form works, much the same as if it were on a new page.

<comment><USER10> It does not remove the visual processing step, it simply reduces the amount of visual processing required.

Eyes tend to automatically fixate on motion. When the whole page transitions the eye has no single point of change/motion to fix on and must scan the whole page to identify the shapes that represent a login form. With a dropdown, the only change/movement is the login form, which the eye is naturally drawn to.

</comment></comment><comment><USER11> just having two fields and login button achieves much more than his method.

it should read second lowest method for login.

</comment><comment><USER12> I have one complaint with the Twitter login dropdown, when you miss the arrow it loads the login page. That's fixed here but it doesn't work without JS. You should probably fix that.

</comment><comment><USER13> To provide another example, there's reddit. Pop-up lightbox style. I've always appreciated it not taking me from what I was reading.

</comment><comment><USER14> Also worth noting how many of those examples use "login" as a verb. "login" is the noun, "log in" is the verb.</comment>


Ask HN: Best choice to build cross platform mobile app with JavaScript? - <AUTHOR> It's 2018 now what's the best choice to build a cross platform mobile app using JavaScript/TypeScript?
I have seen options: - NativeScript - React Native - Ionic
What's your choice and why? <comment><USER2> React Native. Write the React we all know and love, be supported by a huge ecosystem and community, and leverage the power of OS level UI components and libraries whilst enjoying the ease of writing in JS. It's making the production of a truly native-feel app completely painless and with little learning curve for an existing React/JS developer</comment>


Daring Fireball: Apple, Google, and Palm. - <AUTHOR> http://daringfireball.net/2009/02/apple_google_palm

<comment><USER2> It seems ridiculous that using two fingers on a screen can be patented. I would think that the general public would agree.

I've thought that a great strategy for Palm would be to get sued by Apple. Shouldn't that tarnish Apple's great image?

<comment><USER3> Out of the two examples he gives, you found that one to be more objectionable? How about...

 _According to my source, in addition to multi-touch, the other feature that Apple objected to was using a standard headphone jack. Apple apparently owns a patent on controlling software using buttons connected by a standard 3.5mm headphone jack (at least for music and video playback controls), and would not grant Google a license to the patent. Hence the G1's use of a proprietary ExtUSB port rather than a standard 3.5mm headphone jack._

Oh, really?

<comment><USER4> That seems extremely unlikely at best, verging on a conspiracy theory.

<comment><USER3> It seems plausible to me - they're talking about the buttons on the wire going up to the buds communicating back to the device... I'm certainly no expert, but I can't think of any other devices that do that via a standard 3.5mm socket.

<comment><USER5> I doubt they have a patent on the headphone thing. My Nokia N-series phone has a 3.5" headphone jack and it ships with an inline remote that is similar in functionality to the controls on an iPod shuffle. My Sony and Panasonic portable CD players from 10 years ago also had a similar thing.

</comment></comment></comment></comment></comment><comment><USER3> _Apple apparently owns a patent controlling software using buttons connected by a standard 3.5mm headphone jack._

Really, now? Really?

</comment><comment><USER6> Apple is the new Microsoft, Google is the new IBM, Palm is the new Apple.</comment>


Engineer left NASA to make awesome wearable tech Halloween costumes - <AUTHOR> http://picktoread.com/engineer-left-nasa-to-make-awesome-wearable-tech-halloween-costumes/ <comment><USER2> What on Earth is the point of that p2read site?

Here's the article this pointless link massively paraphrases:

[http://www.wired.co.uk/news/archive/2013-08/23/mark-rober- co...](http://www.wired.co.uk/news/archive/2013-08/23/mark-rober-costumes)</comment>


Reviving a 19 Year Old Gameboy Emulator - <AUTHOR> https://nickfa.ro/index.php?title=Reviving_a_19_Year_Old_Gameboy_Emulator <comment><USER2> _The first thing I noticed is that the sound output is going through this convoluted 2-buffer system where it writes to one, and when it fills up, switch to the other_

[https://en.wikipedia.org/wiki/Multiple_buffering](https://en.wikipedia.org/wiki/Multiple_buffering)

I've worked with some Windows audio code before and this is the norm --- while it's playing one buffer, you write to the other one, and switch between the two so the sound card gets an uninterrupted stream of data. In earlier versions of Windows (3.x), the DMA on the sound card would read directly from the buffer.

</comment><comment><USER3> This is a _fantastic_ example of my favorite programming technique:

When nothing makes sense and you're real emotional about it and want to give up... GIVE UP!*

*But you have to write another one from scratch tomorrow because there's good odds you'll do it right on accident and will then be able to diff and understand exactly where you went wrong. Being able to identify this situation and when doing this is useful as early as possible will make you very valuable. The break between attempts is important, go do literally anything else besides code.

I once spent a week going in literal circles because of some degree/radian conversion errors. The rewrite took about 15 minutes.

Never trust anyone's ability to count, not even your own.

It's particularly useful in this exact situation, where the differences are mere +'s and -'s, off by one here or there, maybe a bad copy paste with similar looking variable names. Typically math related

<comment><USER4> > going in _literal_ circles because of some degree/radian conversion errors

Hehe, nice.

And thanks for the tip! Retrying tomorrow is nothing new to me, but I never thought to save yesterday's progress and diff it with the next day's rewrite to figure out _why_ I was stuck.

<comment><USER3> It's especially useful when the changes are so small/subtle that you wouldn't even catch them looking at commit history.

</comment></comment></comment><comment><USER5> > I found (apparently) the only Gameboy emulator written in Pascal, ever: UGE.

Hmm, I don't know. If I've learned anything about programming languages, then it's that the progression of programs written in them is usually: #1 Hello World, #2 Factorial, #3 Gameboy Emulator.

<comment><USER6> Yeah, i think his Google-fu skills need improvement, in another page he mentions that there weren't any IRC clients in Pascal, but i remember at least a couple of IRC libraries for Delphi (and personally i wrote an IRC component in Delphi - you could drop the component on a form and drag-and-drop your way on a simple IRC client, which i used at the time to make dedicated themed clients for the communities i was into :-P).

</comment></comment><comment><USER7> Were all those errors observable back in 2000? It could be that compiler and operating systems differences now are what caused/revealed some bugs. For example the speed problem was probably much less back then due to slower computers.

<comment><USER6> Most likely. For example, this:

> passing in a member of a record rather than a pointer to that record... No > idea why

...sounds like a difference in how the Windows API was exposed. In Delphi and Free Pascal there are two ways to expose a C function that uses a pointer. This:

        void Foo(int* ip);

can be exposed like this:

        procedure Foo(ip: PInteger); cdecl;

or like this:

        procedure Foo(var ip: Integer); cdecl;

The former allows you to pass any pointer to integer, the latter requires an Integer variable reference (which is implemented by the compiler by passing a pointer to the variable). The difference between the two is that you can pass a Nil (Pascal's NULL) to the first, but the second requires a variable.

Older versions of Borland Pascal and Delphi (not sure about newer Delphi versions) used the second declaration style where it made sense, but Free Pascal uses a more direct translation of the Windows headers, opting for the first declaration style.

My guess is that the compiler used by the original author of UGE used the first style.

</comment></comment><comment><USER8> A bit sad that the emulator is running on a personal supercomputer and a spinloop is the solution to slowing it down.

<comment><AUTHOR> If you have any other suggestion I'd like to hear it. Calling sleep or using an OS timer isn't precise enough.

<comment><USER9> What if you tally up the amount of delay you should have done, then when it gets to a big enough granularity where a sleep call would actually give you that amount, sleep.

Eg. Don't try to sleep accurately between the simulated cycles. Let things happen "too fast" for longer and do the delays in batches.

Not sure if this would wind up perceivably too bursty. Just an idea based on things I have seen in other domains.

For the record I don't think spinning is too bad of it's a very short duration, shorter than the scheduler will give you when you take your thread off the CPU.

<comment><AUTHOR> Sleep, at least on Windows, is allowed to have +/\- 15 ms (default system heartbeat interval) of accuracy, which I don't think would work for this case.

[https://docs.microsoft.com/en- us/windows/desktop/api/synchap...](https://docs.microsoft.com/en- us/windows/desktop/api/synchapi/nf-synchapi-sleep)

I could mess around with the Win32 API or the NT API or something to make the heartbeat rate more granular, but according to the docs that kills battery, so I'm guessing it's going to be doing pretty much the same thing as what I'm doing manually.

<comment><USER10> ... that can still work. Measure how much time it actually slept and adjust accordingly. Or, is there some timer that runs at a reasonable rate (100Hz) where you csn yield once you've done 10msec worth of emulation? (I don't know the windows API, so just spitballing from the embedded world here)

<comment><USER3> You seem like you appreciate good timers. If you ever want to revolt in horror/have a few hearty belly laughs, look into how windows has and does handle various granularities of timing

</comment></comment></comment></comment></comment></comment><comment><USER11> I love the content but I also wanted to point out how much I enjoyed your website design. Genuinely confused me for a second!

<comment><USER12> It's powered by MediaWiki. An interesting choice for a blog, though I guess it gives you thinks like content management and update history for free…

</comment></comment><comment><USER13> I'd say the best part of this whole thing is that the original author even made his code available. If he hadn't, we'd be stuck with another broken implementation that nobody could fix or improve long after the author abandoned the project.</comment>