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better pre-impact orbital parameters from today's arxiv
→‎Exploration: I've rewritten this section to make it shorter and a lot more concise. For example, two entire sentences each talking about the orbital period of Dimorphos – one clearly written before the result of the impact came out and one after – have been dispensed in favour of a single sentence fragment that simply details how much the orbital period was shortened by. Imprecise citations of entire Twitter pages have also been removed (WP:TWITTER).
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== Exploration ==
== Exploration ==
On 24&nbsp;November 2021, NASA launched the [[Double Asteroid Redirection Test]] (DART) spacecraft on a [[SpaceX Falcon 9|SpaceX Falcon&nbsp;9]] rocket from [[Vandenberg Space Launch Complex 4|Space Launch Complex&nbsp;4 East]] at [[Vandenberg Space Force Base]] in California, US.<ref name=Greshko-2021-11-23>{{cite news |last=Greshko |first=Michael |date=2021-11-23 |title=This NASA spacecraft will smash into an asteroid – to practice saving Earth |website=[[National Geographic]] |lang=en |url=https://www.nationalgeographic.com/science/article/nasas-dart-spacecraft-will-smash-into-an-asteroid-to-practice-saving-earth |url-status=live |access-date=2021-11-25 |archive-url=https://web.archive.org/web/20211123113703/https://www.nationalgeographic.com/science/article/nasas-dart-spacecraft-will-smash-into-an-asteroid-to-practice-saving-earth |archive-date=2021-11-23 }}</ref><ref>{{cite press release |last=Potter |first=Sean |date=2021-11-23 |title=NASA, SpaceX Launch DART: First test mission to defend planet Earth |website=NASA |url=http://www.nasa.gov/press-release/nasa-spacex-launch-dart-first-test-mission-to-defend-planet-earth |access-date=2021-11-25}}</ref> DART is the first experiment for defending Earth from [[Potentially hazardous object|hazardous asteroids]], and the spacecraft tried to deflect Dimorphos slightly from its position.<ref name=Rincon-2021-11-24>{{cite news |last=Rincon |first=Paul |date=2021-11-24 |title=NASA DART asteroid spacecraft: Mission to smash into Dimorphos space rock launches |lang=en-GB |website=[[BBC News]] |url=https://www.bbc.com/news/science-environment-59327293|access-date=2021-11-25}}</ref> The spacecraft crashed into Dimorphos at a speed of around 15,000&nbsp;mph (6.6&nbsp;km/s)<ref name=Rincon-2021-11-24/> on 26&nbsp;September 2022.<ref>{{cite press release |last=Potter |first=Sean |date=2021-11-23 |title=NASA, SpaceX Launch DART: First test mission to defend planet Earth |website=NASA |publisher=[[National Aeronautics and Space Administration]] |url=http://www.nasa.gov/press-release/nasa-spacex-launch-dart-first-test-mission-to-defend-planet-earth |access-date=2021-11-25}}</ref> The collision brought Dimorphos and Didymos closer to each other and shortened the orbital period.<ref name=Temming-2020-06-29/><ref name=Crane-2021-11-23>{{cite magazine |last=Crane |first=Leah |date=2021-11-23 |title=NASA's DART mission will try to deflect an asteroid by flying into it |magazine=[[New Scientist]] |lang=en-UK |url=https://www.newscientist.com/article/2298530-nasas-dart-mission-will-try-to-deflect-an-asteroid-by-flying-into-it/ |url-status=live |access-date=2021-11-25 |archive-url=https://web.archive.org/web/20211123132010/https://www.newscientist.com/article/2298530-nasas-dart-mission-will-try-to-deflect-an-asteroid-by-flying-into-it/ |archive-date=2021-11-23 }}</ref>
On 24 November 2021, [[NASA]] and the [[Applied Physics Laboratory]] launched a impactor spacecraft towards Dimorphos as part of their [[Double Asteroid Redirection Test]] (DART).<ref name=Greshko-2021-11-23>{{cite news |last=Greshko |first=Michael |date=2021-11-23 |title=This NASA spacecraft will smash into an asteroid – to practice saving Earth |website=[[National Geographic]] |lang=en |url=https://www.nationalgeographic.com/science/article/nasas-dart-spacecraft-will-smash-into-an-asteroid-to-practice-saving-earth |url-status=live |access-date=2021-11-25 |archive-url=https://web.archive.org/web/20211123113703/https://www.nationalgeographic.com/science/article/nasas-dart-spacecraft-will-smash-into-an-asteroid-to-practice-saving-earth |archive-date=2021-11-23 }}</ref><ref>{{cite press release |last=Potter |first=Sean |date=2021-11-23 |title=NASA, SpaceX Launch DART: First test mission to defend planet Earth |website=NASA |url=http://www.nasa.gov/press-release/nasa-spacex-launch-dart-first-test-mission-to-defend-planet-earth |access-date=2021-11-25}}</ref> DART was the first experiment conducted in space to test [[Asteroid impact avoidance|asteroid deflection]] as a method of defending Earth from [[Potentially hazardous object|potentially hazardous asteroids]].<ref name=Rincon-2021-11-24>{{cite news |last=Rincon |first=Paul |date=2021-11-24 |title=NASA DART asteroid spacecraft: Mission to smash into Dimorphos space rock launches |lang=en-GB |website=[[BBC News]] |url=https://www.bbc.com/news/science-environment-59327293|access-date=2021-11-25}}</ref> Following a ten-month journey to the Didymos system, the impactor collided with Dimorphos on 26 September 2022 at a speed of around {{Convert|15000|mph|km/h|abbr=off}}.<ref name=Rincon-2021-11-24/><ref>{{cite press release |last=Potter |first=Sean |date=2021-11-23 |title=NASA, SpaceX Launch DART: First test mission to defend planet Earth |website=NASA |publisher=[[National Aeronautics and Space Administration]] |url=http://www.nasa.gov/press-release/nasa-spacex-launch-dart-first-test-mission-to-defend-planet-earth |access-date=2021-11-25}}</ref> The collision successfully decreased Dimorphos' [[orbital period]] by 32 minutes.<ref name=Temming-2020-06-29/><ref name=Crane-2021-11-23>{{cite magazine |last=Crane |first=Leah |date=2021-11-23 |title=NASA's DART mission will try to deflect an asteroid by flying into it |magazine=[[New Scientist]] |lang=en-UK |url=https://www.newscientist.com/article/2298530-nasas-dart-mission-will-try-to-deflect-an-asteroid-by-flying-into-it/ |url-status=live |access-date=2021-11-25 |archive-url=https://web.archive.org/web/20211123132010/https://www.newscientist.com/article/2298530-nasas-dart-mission-will-try-to-deflect-an-asteroid-by-flying-into-it/ |archive-date=2021-11-23 }}</ref><ref name="DartUpdateNASA">{{cite web |last1=Nelson |first1=Bill |last2=Saccoccia |first2=Giorgio |title=Update on DART Mission to Asteroid Dimorphos (NASA News Conference) |url=https://www.youtube.com/watch?v=Zhzn0U2m5wQ |website=YouTube |access-date=2022-10-11 |language=en}}</ref><ref name="DartPressUpdateNASA">{{cite web |title=NASA Confirms DART Mission Impact Changed Asteroid’s Motion in Space |url=https://www.nasa.gov/press-release/nasa-confirms-dart-mission-impact-changed-asteroid-s-motion-in-space |last=Dunbar |first=Brian |website=NASA |access-date=2022-10-11 |language=en}}</ref> Fifteen days prior to its collision, the impactor released [[LICIACube]], a 6U [[CubeSat]] operated by the [[Italian Space Agency]] that photographed the impact and the resulting dust plume as it performed a close flyby of the Didymos system.<ref name=Greshko-2021-11-23/><ref>{{cite press release |title=DART's small satellite companion tests camera prior to Dimorphos impact |website=NASA.gov |publisher=[[National Aeronautics and Space Administration]] |url=https://www.nasa.gov/feature/dart-s-small-satellite-companion-tests-camera-prior-to-dimorphos-impact |access-date=25 September 2022}}</ref> Observatories such as [[Hubble Space Telescope|Hubble]], [[James Webb Space Telescope|James Webb]], and [[Asteroid Terrestrial-impact Last Alert System|ATLAS]] also captured the dust plume trailing the Didymos system in the days following the impact.<ref name=atlasref>{{cite news|url=https://gizmodo.com/telescopes-capture-dart-asteroid-impact-1849585394|title=Ground Telescopes Capture Jaw-Dropping Views of DART Asteroid Impact|quote=Telescopes around the world honed in on the historic collision, revealing a surprisingly large and bright impact plume.|author=George Dvorsky|date=September 27, 2022|publisher=Gizmodo}}</ref><ref name=LICIACuberef>{{cite news|url=https://gizmodo.com/liciacube-images-dart-asteroid-impact-1849585958 |title=First Asteroid Impact Images from DART’s Companion Show Tentacle-Like Debris Plume|author=George Dvorsky|date=September 27, 2022|publisher=Gizmodo}}</ref><ref>{{cite web |title=LICIACube Impact Images |url=https://www.nasa.gov/feature/first-images-from-italian-space-agency-s-liciacube-satellite |website=NASA |access-date=2 October 2022}}</ref> [[European Space Agency|ESA]] currently plans to launch a spacecraft to the Didymos system in 2024, as part of its [[Hera (space mission)|Hera mission]] to further study the aftermath of the impact.<ref name=Crane-2021-11-23/><ref>{{cite journal |last=Witze |first=Alexandra |date=2021-11-19 |title=NASA spacecraft will slam into asteroid in first planetary-defence test |lang=en |journal=[[Nature (journal)|Nature]] |volume=600 |issue=7887 |doi=10.1038/d41586-021-03471-w |pages=17–18 |pmid=34799719 |bibcode=2021Natur.600...17W |s2cid=244428237 |url=https://www.nature.com/articles/d41586-021-03471-w}}</ref><ref>{{cite journal |last1=Michel |first1=Patrick |last2=Küppers |first2=Michael |last3=Bagatin |first3=Adriano Campo |last4=Carry |first4=Benoit |last5=Charnoz |first5=Sébastien |last6=Leon |first6=Julia de |last7=Fitzsimmons |first7=Alan |last8=Gordo |first8=Paulo |last9=Green |first9=Simon F. |last10=Hérique |first10=Alain |last11=Juzi |first11=Martin |last12=Karatekin |first12=Özgür |last13=Kohout |first13=Tomas |last14=Lazzarin |first14=Monica |last15=Murdoch |first15=Naomi |last16=Okada |first16=Tatsuaki |last17=Palomba |first17=Ernesto |last18=Pravec |first18=Petr |last19=Snodgrass |first19=Colin |last20=Tortora |first20=Paolo |last21=Tsiganis |first21=Kleomenis |last22=Ulamec |first22=Stephan |last23=Vincent |first23=Jean-Baptiste |last24=Wünnemann |first24=Kai |last25=Zhang |first25=Yun |last26=Raducan |first26=Sabina D. |last27=Dotto |first27=Elisabetta |last28=Chabot |first28=Nancy |last29=Cheng |first29=Andy F. |last30=Rivkin |first30=Andy |last31=Barnouin |first31=Olivier |last32=Ernst |first32=Carolyn |last33=Stickle |first33=Angela |last34=Richardson |first34=Derek C. |last35=Thomas |first35=Cristina |last36=Arakawa |first36=Masahiko |last37=Miyamoto |first37=Hirdy |last38=Nakamura |first38=Akiko |last39=Sugita |first39=Seiji |last40=Yoshikawa |first40=Makoto |last41=Abell |first41=Paul |last42=Asphaug |first42=Erik |last43=Ballouz |first43=Ronald-Louis |last44=Bottke |first44=William F. |last45=Lauretta |first45=Dante S. |last46=Walsh |first46=Kevin J. |last47=Martino |first47=Paolo |last48=Carnelli |first48=Ian |display-authors=1| title=The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos |journal=The Planetary Science Journal |date=1 July 2022 |volume=3 |issue=7 |pages=160 |doi=10.3847/psj/ac6f52 |url=https://iopscience.iop.org/article/10.3847/PSJ/ac6f52 |language=en |issn=2632-3338}}</ref>

===Post-impact observations===
The DART spacecraft was accompanied by [[LICIACube]], a six-unit [[CubeSat]] of the [[Italian Space Agency]] (ASI) that was released 15&nbsp;days before impact to record the collision.<ref name=Greshko-2021-11-23/><ref>{{cite press release |title=DART's small satellite companion tests camera prior to Dimorphos impact |website=NASA.gov |publisher=[[National Aeronautics and Space Administration]] |url=https://www.nasa.gov/feature/dart-s-small-satellite-companion-tests-camera-prior-to-dimorphos-impact |access-date=25 September 2022}}</ref> Both LICIACube,<ref>[https://twitter.com/LICIACube LICIACube Twitter feed]</ref> the Hubble and James Webb space telescopes and several Earth-based telescopes, including the [[Asteroid Terrestrial-impact Last Alert System|ATLAS observatory]], have detected the ejecta plume from the DART impact.<ref>[https://twitter.com/fallingstarIfA ATLAS twitter feed]</ref><ref name=atlasref>{{cite news|url=https://gizmodo.com/telescopes-capture-dart-asteroid-impact-1849585394|title=Ground Telescopes Capture Jaw-Dropping Views of DART Asteroid Impact|quote=Telescopes around the world honed in on the historic collision, revealing a surprisingly large and bright impact plume.|author=George Dvorsky|date=September 27, 2022|publisher=Gizmodo}}</ref>
Several images transmitted to Earth show rays of impact debris streaming from Dimorphos.<ref name=LICIACuberef>{{cite news|url=https://gizmodo.com/liciacube-images-dart-asteroid-impact-1849585958 |title=First Asteroid Impact Images from DART’s Companion Show Tentacle-Like Debris Plume|author=George Dvorsky|date=September 27, 2022|publisher=Gizmodo}}</ref><ref>{{cite web |title=LICIACube Impact Images |url=https://www.nasa.gov/feature/first-images-from-italian-space-agency-s-liciacube-satellite |website=NASA |access-date=2 October 2022}}</ref>

While initial results expected a decrease of 10 minutes,<ref name=Rincon-2021-11-24/><ref name=Temming-2020-06-29/> later telescopic and radar observations revealed that the asteroid's orbital period decreased by 32&nbsp;minutes.<ref name="DartUpdateNASA">{{cite web |last1=Nelson |first1=Bill |last2=Saccoccia |first2=Giorgio |title=Update on DART Mission to Asteroid Dimorphos (NASA News Conference) |url=https://www.youtube.com/watch?v=Zhzn0U2m5wQ |website=YouTube |access-date=2022-10-11 |language=en}}</ref><ref name="DartPressUpdateNASA">{{cite web |title=NASA Confirms DART Mission Impact Changed Asteroid’s Motion in Space |url=https://www.nasa.gov/press-release/nasa-confirms-dart-mission-impact-changed-asteroid-s-motion-in-space |last=Dunbar |first=Brian |website=NASA |access-date=2022-10-11 |language=en}}</ref>

The European Space Agency plans to launch the ''[[Hera (space mission)|Hera]]'' spacecraft to Dimorphos in 2024 to study the impact crater and the new orbit of the binary system.<ref name=Crane-2021-11-23/><ref>{{cite journal |last=Witze |first=Alexandra |date=2021-11-19 |title=NASA spacecraft will slam into asteroid in first planetary-defence test |lang=en |journal=[[Nature (journal)|Nature]] |volume=600 |issue=7887 |doi=10.1038/d41586-021-03471-w |pages=17–18 |pmid=34799719 |bibcode=2021Natur.600...17W |s2cid=244428237 |url=https://www.nature.com/articles/d41586-021-03471-w}}</ref><ref>{{cite journal |last1=Michel |first1=Patrick |last2=Küppers |first2=Michael |last3=Bagatin |first3=Adriano Campo |last4=Carry |first4=Benoit |last5=Charnoz |first5=Sébastien |last6=Leon |first6=Julia de |last7=Fitzsimmons |first7=Alan |last8=Gordo |first8=Paulo |last9=Green |first9=Simon F. |last10=Hérique |first10=Alain |last11=Juzi |first11=Martin |last12=Karatekin |first12=Özgür |last13=Kohout |first13=Tomas |last14=Lazzarin |first14=Monica |last15=Murdoch |first15=Naomi |last16=Okada |first16=Tatsuaki |last17=Palomba |first17=Ernesto |last18=Pravec |first18=Petr |last19=Snodgrass |first19=Colin |last20=Tortora |first20=Paolo |last21=Tsiganis |first21=Kleomenis |last22=Ulamec |first22=Stephan |last23=Vincent |first23=Jean-Baptiste |last24=Wünnemann |first24=Kai |last25=Zhang |first25=Yun |last26=Raducan |first26=Sabina D. |last27=Dotto |first27=Elisabetta |last28=Chabot |first28=Nancy |last29=Cheng |first29=Andy F. |last30=Rivkin |first30=Andy |last31=Barnouin |first31=Olivier |last32=Ernst |first32=Carolyn |last33=Stickle |first33=Angela |last34=Richardson |first34=Derek C. |last35=Thomas |first35=Cristina |last36=Arakawa |first36=Masahiko |last37=Miyamoto |first37=Hirdy |last38=Nakamura |first38=Akiko |last39=Sugita |first39=Seiji |last40=Yoshikawa |first40=Makoto |last41=Abell |first41=Paul |last42=Asphaug |first42=Erik |last43=Ballouz |first43=Ronald-Louis |last44=Bottke |first44=William F. |last45=Lauretta |first45=Dante S. |last46=Walsh |first46=Kevin J. |last47=Martino |first47=Paolo |last48=Carnelli |first48=Ian |display-authors=1| title=The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos |journal=The Planetary Science Journal |date=1 July 2022 |volume=3 |issue=7 |pages=160 |doi=10.3847/psj/ac6f52 |url=https://iopscience.iop.org/article/10.3847/PSJ/ac6f52 |language=en |issn=2632-3338}}</ref>


== Footnotes ==
== Footnotes ==

Revision as of 03:54, 12 October 2022

Dimorphos
File:Dimorphos composite.jpg
Dimorphos in September 2022, seconds before the impact of DART
Discovery[1]
Discovered byPravec et al.[a]
Discovery date20 November 2003
Designations
Designation
Didymos I
Pronunciation/daɪˈmɔːrfəs/
Named after
Greek word for "having two forms"[2]
S/2003 (65803) 1
Orbital characteristics[3]
Epoch 7.5 November 2011 (JD 2455873.0)
1.19±0.03 km (pre-impact)
Eccentricity≤ 0.03
11.9216262±0.0000027 hr (11h 55m 18s; pre-impact)[3]
11h 23m ± 2m (post-impact)[4][b]
0.174 m/s (pre-impact)
89.2°±1.8°
Inclination168.6°±1.8° with respect to the ecliptic[c]
Satellite of65803 Didymos
Physical characteristics[5]
Dimensions208 m × 160 m × 133 m[7]
171±11 m[5]
164±18 m[7]
Mass~5×109 kg (assumed)[7]
synchronous?
Albedo0.15±0.04
Spectral type
S
21.3±0.2 (difference from primary)[1]

(65803) Didymos I Dimorphos (provisional designation S/2003 (65803) 1) is a minor-planet moon of the near-Earth asteroid 65803 Didymos, with which it shares a binary system. It has a diameter of 170 metres (560 ft), and has been characterised as a low-density rubble pile. Discovered in 2003 at the Ondřejov Observatory, Dimorphos was the target of the Double Asteroid Redirection Test (DART), a NASA space mission that deliberately collided a spacecraft with the moon in September 2022 to alter its orbit around Didymos. The ESA mission Hera is planned to arrive at the Didymos system in 2026 to further study the effects of the collision on the moon.

Nomenclature

The Working Group Small Body Nomenclature of the International Astronomical Union (IAU) gave the satellite its official name on 23 June 2020.[8] The name is derived from a Greek word Dimorphos (Δίμορφος) meaning "having two forms".[9][10][d] The justification for the new name reads: "As the target of the DART and Hera space missions, it will become the first celestial body in cosmic history whose form was substantially changed as a result of human intervention (the DART impact)".[2] Prior to the IAU naming, the nickname "Didymoon" was used in official communications.[11]

Characteristics

Surface of Dimorphos, captured by DART two seconds before impact.

The primary body of the binary system, Didymos, orbits the Sun at a distance of 1.0–2.3 AU once every 770 days (2 years and 1 month). The pathway of the orbit has an eccentricity of 0.38 and an inclination of 3° with respect to the ecliptic. On 4 October 2022 Didymos will make an Earth approach of 10.6 million km (6.6 million mi).[12] Dimorphos moves in a nearly equatorial, nearly circular orbit around Didymos, with an orbital period of 11.9 hours. Its orbit period is synchronous with its rotation, so that the same side of Dimorphos always faces Didymos. Dimorphos's orbit is retrograde relative to the ecliptic plane, in conformity with Didymos's retrograde rotation.[13]

The final few minutes of pictures from the DART mission revealed an egg-shaped body covered with boulders, clearly indicating it has a rubble pile structure.[14][15] Preliminary LICIACube images of the impact revealed a filamentary plume of dusty ejecta expanding outward from Dimorphos.[16][17] Astronomers using telescopes from Earth as well as the Hubble Space Telescope, James Webb Space Telescope, and the Lucy spacecraft detected significant brightening of the Didymos system as the ejecta plume expanded in a crescent shape.[18]

Dimorphos measures at around 170 metres (560 ft) in diameter, compared to Didymos which is 780 metres (2,560 ft) across.[19] Dimorphos does not have a confirmed mass, but it is estimated to be about 5×109 kg, or about the same mass and size as the Great Pyramid of Giza, when assuming a density of 2.17 g/cm3 similar to Didymos.[20] It is currently the smallest celestial object given a formal name by the IAU.[2]

Observation

Radar images of Didymos and Dimorphos taken by the Arecibo Observatory in 2003

The primary asteroid Didymos was discovered in 1996 by Joe Montani of the Spacewatch Project at the University of Arizona.[1] The satellite Dimorphos was discovered on 20 November 2003, in photometric observations by Petr Pravec and colleagues at the Ondřejov Observatory in the Czech Republic. Dimorphos was detected through periodic dips in Didymos's brightness due to mutual eclipses and occultations. With his collaborators, he confirmed from the Arecibo radar delay-Doppler images that Didymos is a binary system.[21][22]

Exploration

On 24 November 2021, NASA and the Applied Physics Laboratory launched a impactor spacecraft towards Dimorphos as part of their Double Asteroid Redirection Test (DART).[23][24] DART was the first experiment conducted in space to test asteroid deflection as a method of defending Earth from potentially hazardous asteroids.[25] Following a ten-month journey to the Didymos system, the impactor collided with Dimorphos on 26 September 2022 at a speed of around 15,000 miles per hour (24,000 kilometres per hour).[25][26] The collision successfully decreased Dimorphos' orbital period by 32 minutes.[8][27][28][4] Fifteen days prior to its collision, the impactor released LICIACube, a 6U CubeSat operated by the Italian Space Agency that photographed the impact and the resulting dust plume as it performed a close flyby of the Didymos system.[23][29] Observatories such as Hubble, James Webb, and ATLAS also captured the dust plume trailing the Didymos system in the days following the impact.[30][31][32] ESA currently plans to launch a spacecraft to the Didymos system in 2024, as part of its Hera mission to further study the aftermath of the impact.[27][33][34]

Footnotes

  1. ^ Astronomers involved in the discovery of Dimorphos include P. Pravec, L.A.M. Benner, M.C. Nolan, P. Kusnirak, D. Pray, J.D. Giorgini, R.F. Jurgens, S.J. Ostro, J.-L. Margot, C. Magri, A. Grauer, and S. Larson. The discovery used lightcurve and radar observations from the Jet Propulsion Laboratory, Pasadena, CA; National Astronomy and Ionosphere Center / Arecibo Observatory, Arecibo, PR; and Ondrejov Observatory, Ondřejov, CZ. [1]
  2. ^ Orbital parameters are those after the impact of DART, which changed the orbital period by 32 minutes. Other possibly changed parameters remain to be reevaluated.[4]
  3. ^ Scheirich and Pravec (2022) give the Dimorphos's orbit pole orientation in terms of ecliptic coordinates, where λ is ecliptic longitude and β is ecliptic latitude.[5]: 4  β is the angular offset from the ecliptic plane, whereas inclination i with respect to the ecliptic is the angular offset of the orbital pole from the ecliptic north pole, at β = +90° ; i with respect to the ecliptic would be the complement of β.[6] Therefore, given β = –78.6° , i = 90° – (–78.6°) = 168.6° from the ecliptic.
  4. ^ The name "Δίμορφος" was suggested by planetary scientist Kleomenis Tsiganis at the Aristotle University of Thessaloniki. Tsiganis explained that the name "has been chosen in anticipation of its changes: It will be known to us in two very different forms, the one seen by DART before the impact, and the other seen by Hera a few years later".[2]

References

  1. ^ a b c d "(65803) Didymos". www.johnstonsarchive.net. Retrieved 11 November 2021.
  2. ^ a b c d "IAU approves name of target of first NASA and ESA planetary defence missions". iau.org (Press release). International Astronomical Union. 23 June 2020. Retrieved 1 July 2020.
  3. ^ a b Naidu, Shantanu P.; Chesley, Steven R.; Farnocchia, Davide; Moskovitz, Nick; Pravec, Petr; Scheirich, Petr; Thomas, Cristina; Rivkin, Andrew S. (October 2022). "Anticipating the DART impact: Orbit estimation of Dimorphos using a simplified model". arXiv:2210.05101 [astro-ph.EP].
  4. ^ a b c Dunbar, Brian. "NASA Confirms DART Mission Impact Changed Asteroid's Motion in Space". NASA. Retrieved 11 October 2022.
  5. ^ a b c Scheirich, P.; Pravec, P. (July 2022). "Preimpact Mutual Orbit of the DART Target Binary Asteroid (65803) Didymos Derived from Observations of Mutual Events in 2003–2021". The Planetary Science Journal. 3 (7): 12. Bibcode:2022PSJ.....3..163S. doi:10.3847/PSJ/ac7233. S2CID 250650906. 163.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  6. ^ "Coordinate transformations". Astronomy and Astrophysics. European Southern Observatory. January 1998. Archived from the original on 17 June 2021. Retrieved 17 June 2022.
  7. ^ a b c Nakano, Ryota; Hirabayashi, Masatoshi; Brozovic, M.; Nolan, M. C.; Ostro, S. J.; Margot, J. L.; et al. (July 2022). "NASA's Double Asteroid Redirection Test (DART): Mutual Orbital Period Change Due to Reshaping in the Near-Earth Binary Asteroid System (65803) Didymos". The Planetary Science Journal. 3 (7): 16. Bibcode:2022PSJ.....3..148N. doi:10.3847/PSJ/ac7566. S2CID 250327233. 148.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  8. ^ a b Temming, Maria (29 June 2020). "An asteroid's moon got a name so NASA can bump it off its course". Science News. Retrieved 1 July 2020.
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  • Media related to Dimorphos at Wikimedia Commons
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