NASA Confirms DART Mission Impact Changed Asteroid’s Motion in Space
This imagery from NASA’s Hubble Space Telescope from Oct. 8, 2022, shows the debris blasted from the surface of Dimorphos 285 hours after the asteroid was intentionally impacted by NASA’s DART spacecraft on Sept. 26. The shape of that tail has changed over time. Scientists are continuing to study this material and how it moves in space, in order to better understand the asteroid.
Credit: NASA/European Space Agency/Space Telescope Science Institute/Hubble
Tue, 10/11/2022 - 12:50
Analysis of data obtained over the past two weeks by NASA’s Double Asteroid Redirection Test (DART) investigation team shows the spacecraft’s kinetic impact with its target asteroid, Dimorphos, successfully altered the asteroid’s orbit. This marks humanity’s first time purposely changing the motion of a celestial object and the first full-scale demonstration of asteroid deflection technology.
Prior to DART’s impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos. Since DART’s intentional collision with Dimorphos on Sept. 26, astronomers have been using telescopes on Earth to measure how much that time has changed. Now, the investigation team has confirmed the spacecraft’s impact altered Dimorphos’ orbit around Didymos by 32 minutes, shortening the 11 hour and 55 minute orbit to 11 hours and 23 minutes. This measurement has a margin of uncertainty of approximately plus or minus 2 minutes.
Before DART’s encounter, NASA had defined a minimum successful orbit period change of Dimorphos as a change of 73 seconds or more. This early data show DART surpassed this minimum benchmark by more than 25 times.
“This result is one important step toward understanding the full effect of DART’s impact with its target asteroid” said Lori Glaze, director of
NASA’s Planetary Science Division at NASA Headquarters in Washington. “As new data come in each day, astronomers will be able to better assess whether, and how, a mission like DART could be used in the future to help protect Earth from a collision with an asteroid if we ever discover one headed our way.”
The investigation team is still acquiring data with ground-based observatories around the world — as well as with radar facilities at NASA Jet Propulsion Laboratory’s Goldstone planetary radar in California and the National Science Foundation’s Green Bank Observatory in West Virginia. They are updating the period measurement with frequent observations to improve its precision.
Focus now is shifting toward measuring the efficiency of momentum transfer from DART’s roughly 14,000 mile (22,530 kilometer) per hour collision with its target. This includes further analysis of the “ejecta” — the many tons of asteroidal rock displaced and launched into space by the impact. The recoil from this blast of debris substantially enhanced DART’s push against Dimorphos — a little like a jet of air streaming out of a balloon sends the balloon in the opposite direction.
To understand the effect of the recoil from the ejecta, more information on the asteroid’s physical properties, such as the characteristics of its surface, and how strong or weak it is, is needed. These issues are still being investigated.
“DART has given us some fascinating data about both asteroid properties and the effectiveness of a kinetic impactor as a planetary defense technology,” said Nancy Chabot, the DART coordination lead from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland. “The DART team continues to work on this rich data set to fully understand this first planetary defense test of asteroid deflection. ”
For this analysis, astronomers will continue to study imagery of Dimorphos from DART’s terminal approach and from the Light Italian CubeSat for Imaging of Asteroids (LICIACube), provided by the Italian Space Agency, to approximate the asteroid’s mass and shape. Roughly four years from now, the European Space Agency’s Hera project is also planned to conduct detailed surveys of both Dimorphos and Didymos, with a particular focus on the crater left by DART’s collision and a precise measurement of Dimorphos’ mass.
Johns Hopkins APL built and operated the DART spacecraft and manages the DART mission for NASA’s Planetary Defense Coordination Office as a project of the agency’s Planetary Missions Program Office. Telescopic facilities contributing to the observations used by the DART team to determine this result include: Goldstone, Green Bank Observatory, the Swope Telescope at the Las Campanas Observatory in Chile, the Danish Telescope at the La Silla Observatory in Chile, and the Las Cumbres Observatory global telescope network facilities in Chile and in South Africa.
Neither Dimorphos nor Didymos has ever posed any hazard to Earth before or after DART’s controlled collision with Dimorphos.
For more information about the DART mission, visit https://www.nasa.gov/dart.
The Applied Physics Laboratory, a not-for-profit division of The Johns Hopkins University, meets critical national challenges through the innovative application of science and technology. For more information, visit www.jhuapl.edu.
NASA imethibitisha kuwa athari ya DART imebadilisha mwendo wa sayari ndogo katika anga, picha hii kutoka kwa Darfur ya NASA ya Hubble Space Telescope kutoka Oktoba 8, 2022 inaonyesha mabaki yaliyotolewa kutoka kwa uso wa Dimorphos masaa 285 baada ya asteroid hiyo kugongwa na DART mnamo Septemba 26. Umbo la mkia huo limebadilika kadiri wakati unavyopita. Wanasayansi wanaendelea kujifunza nyenzo hii na jinsi inavyohamia angani, ili kuelewa vizuri zaidi sayari hiyo ndogo. NASA na Shirika la Anga la Ulaya (ESA) na Taasisi ya Sayansi ya Teleskopi ya Anga (STI) na Hubble, 10 11 22 - 12: 50 Uchambuzi wa data zilizopatikana katika wiki mbili zilizopita na timu ya uchunguzi ya NASA ya Double Asteroid Redirection Test (DART) inaonyesha athari ya kinetic ya chombo cha anga na asteroid yake ya lengo, Dimorphos, ilibadilisha kwa mafanikio mzunguko wa asteroid. Hii ni mara ya kwanza kwa ubinadamu kubadilisha kwa makusudi mwendo wa kitu cha angani na maonyesho ya kwanza ya kiwango kamili cha teknolojia ya kupotosha asteroid. Kabla ya kugonga kwa DART, Dimorphos ilichukua masaa 11 na dakika 55 kuzunguka asteroid yake kubwa, Didymos. Tangu mgongano wa DART na Dimorphos Septemba 26, wataalamu wa nyota wamekuwa wakitumia darubini za juu duniani kupima jinsi muda umebadilika. "Tumekuwa tukikubaliana na uchunguzi wa NASA kwamba ""mpaka sasa, mlipuko wa Dimorphos umebadilisha mzunguko wa Didymos kwa dakika 32, na kuupunguza mzunguko wa saa 11 na dakika 55 hadi saa 11 na dakika 23.""" Utaratibu huu una margin ya kutokuwa na uhakika ya karibu plus au minus dakika mbili. Kabla ya kukutana na DART, NASA ilikuwa imeweka kiwango cha chini cha mafanikio ya mabadiliko ya kipindi cha mzunguko wa Dimorphos kama mabadiliko ya sekunde 73 au zaidi. Takwimu za awali zinaonyesha DART ilizidi kiwango hiki cha chini zaidi ya mara 25. "Hati hii ni hatua muhimu kuelekea kuelewa athari kamili ya athari ya DART na asteroid yake ya lengo, ""alisema Lori Glaze, mkurugenzi wa Idara ya Sayari ya Sayari ya NASA katika Makao Makuu ya NASA huko Washington." "Wakati data mpya zinapokuja kila siku, wataalamu wa nyota wataweza kutathmini vizuri ikiwa, na jinsi, ujumbe kama DART unaweza kutumika katika siku zijazo kusaidia kulinda Dunia kutoka kwa mgongano na asteroid ikiwa tutagundua moja inayoelekea njia yetu. ""Timu ya uchunguzi bado inapata data na vituo vya uchunguzi vya ardhi ulimwenguni kote, pamoja na vifaa vya rada katika NASA Jet Propulsion Laboratory's Goldstone Planetary Radar huko California na National Science Foundation's Green Bank Observatory huko West Virginia." Wao ni kusasisha kipimo kipindi na uchunguzi mara kwa mara ili kuboresha usahihi wake. Sasa, lengo la utafiti huo ni kupima ufanisi wa kuhamisha mwendo kutoka kwa mgongano wa DART wa kilomita 14,500 kwa saa na lengo lake. Hii inajumuisha uchambuzi zaidi wa "ejecta" - tani nyingi za mwamba wa asteroid zilizohamishwa na kutolewa angani na athari. Mshuko kutoka mlipuko huu wa mabaki kwa kiasi kikubwa kuimarishwa DART's kushinikiza dhidi ya Dimorphos <unk> kidogo kama jet ya hewa mkondo nje ya puto hutuma puto katika mwelekeo kinyume. Ili kuelewa athari ya recoil kutoka ejecta, habari zaidi juu ya mali ya fizikia ya asteroid, kama vile sifa za uso wake, na jinsi nguvu au dhaifu ni, inahitajika. Masuala hayo bado yanachunguzwa. "DART imetupa data ya kuvutia kuhusu mali zote mbili za asteroid na ufanisi wa mshtuko wa kinetic kama teknolojia ya ulinzi wa sayari, "alisema Nancy Chabot, kiongozi wa uratibu wa DART kutoka Maabara ya Fizikia ya Matumizi ya Johns Hopkins (APL) huko Laurel, Maryland." <unk>Timu ya DART inaendelea kufanya kazi kwenye seti hii tajiri ya data kuelewa kikamilifu mtihani huu wa kwanza wa ulinzi wa sayari ya kupotoka kwa asteroid. Kwa ajili ya uchambuzi huu, wataalamu wa nyota wataendelea kusoma picha za Dimorphos kutoka kwa njia ya mwisho ya DART na kutoka kwa Light Italian CubeSat kwa Picha ya Asteroids (LICIACube), iliyotolewa na Shirika la Anga la Italia, ili kukadiria uzito na umbo la asteroid. Katika miaka minne ijayo, mradi wa Hera wa Shirika la Anga la Ulaya pia umepangwa kufanya uchunguzi wa kina wa Dimorphos na Didymos, na kuzingatia hasa kreta iliyobaki kutokana na mgongano wa DART na kipimo sahihi cha wingi wa Dimorphos. Johns Hopkins APL ilijenga na kuendesha chombo cha anga cha DART na inasimamia utume wa DART kwa Ofisi ya Uratibu wa Ulinzi wa Sayari ya NASA kama mradi wa Ofisi ya Programu ya Ujumbe wa Sayari ya shirika. Vifaa vya telescopic vinavyoshiriki katika uchunguzi uliotumiwa na timu ya DART kuamua matokeo haya ni pamoja na: Goldstone, Green Bank Observatory, Swope Telescope katika Las Campanas Observatory nchini Chile, Danish Telescope katika La Silla Observatory nchini Chile, na Las Cumbres Observatory Global Telescope Network katika Chile na Afrika Kusini. Wala Dimorphos wala Didymos haijawahi kuwa hatari kwa Dunia kabla au baada ya mgongano uliodhibitiwa wa DART na Dimorphos. Kwa maelezo zaidi kuhusu DART, tembelea www.nasa.gov. Maabara ya Fizikia ya Matumizi, mgawanyiko usio wa faida wa Chuo Kikuu cha Johns Hopkins, hukutana na changamoto muhimu za kitaifa kupitia matumizi ya ubunifu ya sayansi na teknolojia. Kwa habari zaidi, tembelea www.jhuapl.edu.