article_snippet: But while nuclear is often said to be the 'holy grail', the team found it did not noticeably shorten the mission over other versions.
article_snippet: But while a nuclear engine is often touted as the holy grail of space travel, the team found that for a mission to Mars, there was no benefit in such an engine.
article_snippet: While it might be slightly faster, the mission time is still similar overall, but such an engine would cost and weight a lot more.
article_snippet: Nasa actually attempted to build a nuclear-powered engine before, known as Nerva (Nuclear Engine for Rocket Vehicle Application), with a view to using it to get to Mars, but the programme was scrapped in 1972.
article_snippet: Nasa actually attempted to build a nuclear-powered engine before, known as Nerva (Nuclear Engine for Rocket Vehicle Application), shown in this illustration, with a view to using it to get to Mars, but the programme was scrapped in 1972 .
article_snippet: Dr Bertolami says a problem arises because, while nuclear propulsion could accelerate to quite high speeds, a problem needs to brake again to enter orbit around the red planet.
article_snippet: While it might be able to reach higher speeds for a mission to Mars over chemical and ion propulsion, the amount it would have to brake means that it doesn't really reduce the time of the mission by any considerable margin.
article_snippet: And the weight of hoisting a nuclear reactor into orbit, coupled with the cost, does not make it an attractive option.
article_snippet: However, looking further into the future, Dr Bertolami said if humans were to travel beyond Mars - such as to a moon of Jupiter - then nuclear propulsion becomes feasible.
article_snippet: ‘Beyond Mars then the issue is indeed to do the issue as fast as possible, and then I would think that nuclear propulsion would turn out to be the most interesting one,’ Dr Bertolami said.