Double Asteroid Redirection Test

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Double Asteroid Redirection Test
Dart header 2 (1).jpg
Illustration of the DART impactor spacecraft and LICIACube approaching Dimorphos.
NamesDART
Mission typePlanetary defense mission
OperatorNASA  / APL
COSPAR ID2021-110A
SATCAT no.49497
Websitenasa.gov/planetarydefense/dart
dart.jhuapl.edu/Mission/index.php
Mission duration11 months (planned),
8 months and 16 days (in progress)
Spacecraft properties
Spacecraft
ManufacturerApplied Physics Laboratory
of Johns Hopkins University
Launch massDART: 610 kg (1,340 lb),
LICIACube: 14 kg (31 lb)
DimensionsDART: 1.8 × 1.9 × 2.6 m (5 ft 11 in × 6 ft 3 in × 8 ft 6 in)
ROSA: 8.5 × 2.4 m (27.9 × 7.9 ft) (each)
Power6.6 kW
Start of mission
Launch date24 November 2021, 06:21:02 UTC
RocketFalcon 9 Block 5, B1063.3
Launch siteVandenberg, SLC-4E
ContractorSpaceX
Flyby of Didymos system
Spacecraft componentLICIACube
Closest approach26 September 2022 (planned)
Distance55 km (34 mi)
Dimorphos impactor
Impact date26 September 2022 (planned)
Instruments
Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO)
DART Mission Patch.png
DART mission patch  

Double Asteroid Redirection Test (DART) is a NASA space mission aimed at testing a method of planetary defense against near-Earth objects (NEOs). Launched from Earth in November 2021, the mission will deliberately crash a space probe into the minor-planet moon Dimorphos of the double asteroid Didymos to assess the future potential of a spacecraft impact to deflect an asteroid on a collision course with Earth through a transference of momentum. The asteroid poses no actual threat to Earth; it was merely selected for the test.

DART is a joint project between NASA and the Johns Hopkins Applied Physics Laboratory (APL). The project is administered by NASA's Planetary Defense Coordination Office, and several NASA laboratories and offices are providing technical support. International partners, such as the European Space Agency (ESA), Italian Space Agency (ASI), and Japan Aerospace Exploration Agency (JAXA), are contributing to related or subsequent projects. In August 2018, NASA approved the project to start the final design and assembly phase. The DART spacecraft was successfully launched on 24 November 2021, with collision slated for 26 September 2022 to 2 October 2022.[1][2]

Background[edit]

Originally, the European Space Agency (ESA) and NASA had independent plans for missions to test asteroid deflection strategies, and by 2015 they struck a collaboration called AIDA (Asteroid Impact & Deflection Assessment) involving two separate spacecraft launches that work in synergy.[3][4][5] Under the proposal, the European spacecraft, AIM, would have launched in December 2020, and DART in July 2021. AIM would have orbited the larger asteroid to study its composition and that of its moon. DART would then kinetically impact the asteroid's moon on September, 26th, 2022, during a close approach to Earth.[4] AIM would have studied the asteroid's strength, surface physical properties, and internal structure, as well as measure the effect on the asteroid moon's orbit around the larger asteroid.[citation needed]

The flash and resulting ejecta from 2005 Deep Impact collision with the comet Tempel 1.[6]

This method of asteroid impact avoidance has already been implemented once, for a completely different purpose (analysis of the structure and composition of a comet), by NASA's 370 kg (820 lb) Deep Impact space probe. On impact, it released 19 gigajoules of energy (the equivalent of 4.8 tons of TNT),[7][8][9][10] decreased the perihelion of Comet Tempel 1 by 10 m (33 ft), changed orbit by 10 cm (3.9 in), and a predicted 0.0001 mm/s (0.014 in/h) velocity change after impacting the comet at the speed of ~10.2 km/s (6.3 mi/s) on July 4, 2005.[6]

The AIM orbiter was cancelled, then replaced by Hera, that would observe the asteroid four years after the DART impact. The effects of the impact by DART would have then been monitored live from ground-based telescopes and radar.[11][5]

In June 2017, NASA approved a move from concept development to the preliminary design phase,[12] and in August 2018 NASA approved the project to start the final design and assembly phase.[13]

On 11 April 2019, NASA announced that a SpaceX Falcon 9 would be used to launch DART.[14]

Description[edit]

Spacecraft[edit]

The DART spacecraft is an impactor with a mass of 610 kg (1,340 lb),[15] that hosts no scientific payload and has only sensors for navigation such as a Sun sensor, a star tracker called SMART Nav software (Small-body Maneuvering Autonomous Real Time Navigation),[16] and a 20 cm (7.9 in) aperture camera called Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO). DRACO is based on the Long Range Reconnaissance Imager (LORRI) onboard New Horizons spacecraft, and will support autonomous navigation to impact the asteroid's moon at its center. The optical part of DRACO is a Ritchey-Chrétien telescope equipped with telephoto lens with a field of view of 0.29° and a focal length of f/12.60. The detector, of CMOS type, has 2,560 × 2,160 pixels. The spatial resolution of the images recorded immediately before the impact is 20 centimeters. The detector records the wavelength range from 0.4 to 1 micron (visible and near infrared). The instrument has a mass of 8.66 kg (19.1 lb).[17]

DART spacecraft uses the NEXT ion thruster, a type of solar electric propulsion.[11][18] It will be powered by 22 m2 (240 sq ft) solar arrays to generate the ~3.5 kW needed to power the NASA Evolutionary Xenon Thruster–Commercial (NEXT-C) engine.[19]

The spacecraft's solar arrays use a Roll Out Solar Array (ROSA) design, that was tested on the International Space Station (ISS) in June 2017 as part of Expedition 52.[20]

Using ROSA as the structure, a small portion of the DART solar array is configured to demonstrate Transformational Solar Array technology, which has very-high-efficiency solar cells and reflective concentrators providing three times more power than current solar array technology.[21][22]

The DART spacecraft is the first spacecraft to use a new type of high gain communication antenna, that is, a Spiral Radial Line Slot Array (RLSA). The antenna operates at the X-band NASA Deep Space Network (NASA DSN) frequencies of 7.2 and 8.4 GHz. The fabricated antenna in a flat and compact shape exceeds the given requirements and has been tested through environments resulting in a TRL-6 design.[23]

Course of the Impact[edit]

A month before the impact, the DRACO camera detects the Didymos system and refines its trajectory. Ten days before the impact, the LICIACube nano-satellite is released. Four hours before impact, DART becomes completely autonomous and implements its SMART Nav guidance system. Three hours before impact, when the target is 176,000 km (109,000 mi) away , DART performs an inventory of objects near the target. The final trajectory is fixed 90 minutes before the collision when the asteroid is 38,000 km (24,000 mi) away from Dimorphos. While it is 24,000 km (15,000 mi) away from Dimorphos begins to be observable (1.4 pixels). Until impact DRACO takes continuous images of the asteroid's surface which are transmitted in real time. In the last minutes, trajectory corrections are no longer allowed so that the images taken by DRACO (the only ones to provide a detailed view of the surface of Dimorphos) remain sharp. Indeed, due to the length of the solar panels, each use of the propulsion causes vibrations that make the images blurry. The last image, transmitted two seconds before impact, should have a spatial resolution of less than 20 centimeters. The impact takes place between September 26 and October 1, 2022.

The impact of the 500 kg (1,100 lb)[24] DART at 6.6 km/s (4.1 mi/s) [25][26] will produce an estimated velocity change on the order of 0.4 mm/s, which leads to a small change in trajectory of the asteroid system, but over time, it leads to a large shift of path.[27][4][28][29] Over a span of years, the cumulative trajectory change from such a small change in velocity could mitigate the risk of a hypothetical Earth-bound asteroid hitting Earth.[30] The impact will target the center of figure of Dimorphos and should decrease the orbital period, currently 11.92 hours, by roughly 10 minutes.[15]

Sequence of operations for impact[31]
Date

(before impact)

Distance Asteroid size

(DRACO camera)

Events
T-30 days The DRACO camera detects Didymos
T-10 days Ejection of the LICIACube nano-satellite which maneuvers to avoid crashing into the asteroid.
T-4 hours Start of autonomous navigation (SMART Nav software)
T-60 mins 24,000 km (15,000 mi) Didymos : 6.5 pixels

Dimorphos : 1.4 pixels

The DRACO camera detects Dimorphos
T-4 mins 1,600 km (990 mi) Didymos : 99 pixels

Dimorphos : 21 pixels

Start of last course correction
T-2 mins 800 km (500 mi) Didymos : 99 pixels

Dimorphos : 21 pixels

End of last course correction
T-20 seconds 130 km (81 mi) Dimorphos : 300 pixels The photos taken reach the expected spatial resolution.
T-0 0 km (0 mi) Impacting Dimorphous.
T+3 minutes Flyby of the asteroid by LICIACube.
Infographic showing the effect of DART's impact on the orbit of Didymos B while deployment of LICIACube

Effect of the impact on the orbit of Dimorphos and Didymos[edit]

The spacecraft must hit Dimorphos in the opposite direction to the asteroid's motion. The actual velocity change and orbital shift are unknown until after it because it depends on the topology of the surface. Following the impact, the orbital speed of Dimorphos drops slightly, which has the effect of reducing the radius of its orbit around Didymos. The trajectory of Didymos is modified in reduced proportions because the mass of Dimorphos is much lower than that of Didymos. There is a poorly predictable "momentum enhancement" effect due to the contribution of recoil momentum from impact ejecta.[32] The final momentum transferred to the largest remaining fragment of the asteroid could be up to 3-5 times the incident momentum, and obtaining accurate measurements of the effects, which will help refine models of such impacts, is one of the mission's main goals.[33] Initial estimates of the change in binary orbit period should be known within a week.[34] A detailed reconnaissance and assessment will be performed a few years later by a spacecraft called Hera, approved by ESA in November 2019.[35][36]

Secondary spacecraft[edit]

LICIACube CubeSat, a companion satellite of the DART spacecraft

The Italian Space Agency (ASI) will contribute a secondary spacecraft called LICIACube (Light Italian CubeSat for Imaging of Asteroids), a small CubeSat that will piggyback with DART and will separate 10 days before impact to acquire images of the impact and ejecta as it drifts past the asteroid.[35][37] LICIACube will communicate directly with Earth, sending back images of the ejecta after the Dimorphos flyby.[38] LICIACube is equipped with two optical cameras, dubbed LUKE and LEIA.[39]

Follow-up mission[edit]

In a collaborating project, the European Space Agency is developing Hera, a spacecraft that will be launched to Didymos in 2024[40] and arrive in 2027[41] (5 years after DART's impact), to do a detailed reconnaissance and assessment.[40] Hera would carry two CubeSats, Milani and Juventas.[40]

AIDA mission architecture[edit]

DART satellite, showing its only instrument, the DRACO camera (illustration)
Host spacecraft Secondary spacecraft Remarks
DART LICIACube[42]
  • By the Italian Space Agency
  • 6U CubeSat
  • LUKE (LICIACube Unit Key Explorer) Camera and LEIA (LICIACube Explorer Imaging for Asteroid) Camera
Hera Juventas[43][44]
  • By GomSpace and GMV
  • 6U CubeSat orbiter
  • Camera, JuRa monostatic low-frequency radar,[45] accelerometers, and gravimeter [46]
  • Will attempt to land on the asteroid surface[44][46]
Milani[47]
  • By Italy/Czech/Finnish consortium
  • 6U CubeSat orbiter
  • VIS/Near-IR spectrometer, volatile analyzer
  • Will characterize Didymos and Dimorphos surface composition and the dust environment around the system
  • Will perform technology demonstration experiments
SCI

Mission profile[edit]

Shape model of Didymos and its satellite Dimorphos, based on photometric light curve and radar data

Target asteroid[edit]

The mission's target is Dimorphos in 65803 Didymos system, a binary asteroid system in which one asteroid is orbited by a smaller one. The primary asteroid (Didymos A) is about 780 m (2,560 ft) in diameter; the asteroid moon Dimorphos (Didymos B) is about 160 m (520 ft) in diameter in an orbit about 1 km (0.62 mi) from the primary.[11] The mass of the Didymos system is estimated at 528 billion kg, with Dimorphos composing 4.8 billion kg of that total.[15] DART will target the smaller asteroid Dimorphos. The Didymos system is not an Earth-crossing asteroid, and there is no possibility that the deflection experiment could create an impact hazard.[28]

Preflight preparations[edit]

Falcon 9 rocket's payload fairing being attached to NASA's Double Asteroid Redirection Test (DART) spacecraft on 16 November 2021
Animation of DART's trajectory
  DART ·   65803 Didymos ·   Earth ·   Sun ·   2001 CB21 ·   3361 Orpheus
Falcon 9 and DART vertical at SLC-4E

Launch preparations for DART began on 20 October 2021, as the spacecraft began fueling at Vandenberg Space Force Base in California.[50] The spacecraft arrived at Vandenberg Space Force Base (VSFB) near Lompoc, in early October 2021 after a cross-country drive. DART team members have since been preparing the spacecraft for flight, testing the spacecraft's mechanisms and electrical system, wrapping the final parts in multilayer insulation blankets, and practicing the launch sequence from both the launch site and the mission operations center at APL. DART headed to the SpaceX Payload Processing Facility on VSFB on 26 October 2021. Two days later, the team received the green light to fill DART's fuel tank with roughly 50 kg (110 lb) of hydrazine propellant for spacecraft maneuvers and attitude control. DART also carries about 60 kg (130 lb) of xenon for the NEXT-C ion engine. Engineers loaded the xenon before the spacecraft left APL in early October 2021.[51]

Starting on 10 November 2021, engineers mated the spacecraft to the adapter that stacks on top of the SpaceX Falcon 9 launch vehicle. The Falcon 9 rocket without the payload fairing rolled for a static fire and later came back to the processing facility again where technicians with SpaceX installed the two halves of the fairing around the spacecraft over the course of two days, November 16 and 17, inside the SpaceX Payload Processing Facility at Vandenberg Space Force Base in California and the ground teams completed a successful Flight Readiness Review later that week with the fairing then attached to the rocket.[52]

A day before launch, the launch vehicle rolled out of the hangar and onto the launch pad at Vandenberg Space Launch Complex 4 (SLC-4E); from there it lifted off to begin DART's journey to the Didymos system and it propelled the spacecraft into space.[51]

Launch[edit]

The DART spacecraft was launched on 24 November 2021, at 06:21:02 UTC.

Early planning suggested that DART was to be deployed into a high altitude, high eccentricity Earth orbit designed to avoid the Moon. In such a scenario, DART would use its low thrust, high efficiency NEXT ion engine to slowly escape from its high Earth orbit to a slightly inclined near-Earth solar orbit, from which it would maneuver onto a collision trajectory with its target. But because DART was launched as a dedicated Falcon 9 mission, the payload along with Falcon 9's second stage was placed directly on an Earth escape trajectory and into heliocentric orbit when the second stage reignited for a second engine startup or escape burn. Thus, although DART carries a first-of-its-kind electric thruster and plenty of xenon fuel, Falcon 9 did almost all of the work, leaving the spacecraft to perform only a few trajectory-correction burns with simple chemical thrusters as it homes in on Didymos's moon Dimorphos.[53]

Transit[edit]

The transit phase to the goal lasts about 9 months. On March 6, 2022, the space probe must pass not far from the asteroid 2001 CB 21 (578 m (1,896 ft) in diameter). It takes advantage of this overflight to calibrate by its sensors.[54][16][55][31][56]

Gallery[edit]

See also[edit]

References[edit]

  1. ^ "SpaceX ready for first launch with NASA interplanetary mission". Spaceflight Now. 22 November 2021. Retrieved 24 November 2021.
  2. ^ "DART Launch Moves to Secondary Window". NASA. 17 February 2021. Retrieved 24 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  3. ^ AIDA DART Home page at APL
  4. ^ a b c "Asteroid Impact & Deflection Assessment (AIDA) study". Archived from the original on 7 June 2015.
  5. ^ a b DART at Applied Physics Laboratory Johns Hopkins University
  6. ^ a b "Chapter 10 – Comets Astronomy 9601" (PDF). Archived from the original (PDF) on 7 November 2016.
  7. ^ "NASA - Deep Impact's Impactor". www.nasa.gov. Archived from the original on 23 June 2016.
  8. ^ Richardson, James E.; Melosh, H. Jay; Lisse, Carey M.; Carcich, Brian (2007). "A ballistics analysis of the Deep Impact ejecta plume: Determining Comet Tempel 1's gravity, mass, and density". Icarus. 191 (2): 176–209. Bibcode:2007Icar..191S.176R. CiteSeerX 10.1.1.205.4928. doi:10.1016/j.icarus.2007.08.033.
  9. ^ Schleicher, David G.; Barnes, Kate L.; Baugh, Nicole F. (2006). "Photometry and Imaging Results for Comet 9P/Tempel 1 and Deep Impact: Gas Production Rates, Postimpact Light Curves, and Ejecta Plume Morphology". The Astronomical Journal. 131 (2): 1130–1137. Bibcode:2006AJ....131.1130S. doi:10.1086/499301.
  10. ^ A'Hearn, M. F.; Belton, M. J. S.; Delamere, W. A.; Kissel, J.; Klaasen, K. P.; McFadden, L. A.; Meech, K. J.; Melosh, H. J.; Schultz, P. H.; Sunshine, J. M.; Thomas, P. C.; Veverka, J.; Yeomans, D. K.; Baca, M. W.; Busko, I.; Crockett, C. J.; Collins, S. M.; Desnoyer, M.; Eberhardy, C. A.; Ernst, C. M.; Farnham, T. L.; Feaga, L.; Groussin, O.; Hampton, D.; Ipatov, S. I.; Li, J.-Y.; Lindler, D.; Lisse, C. M.; Mastrodemos, N.; Owen, W. M.; Richardson, J. E.; Wellnitz, D. D.; White, R. L. (14 October 2005). "Deep Impact: Excavating Comet Tempel 1". Science. 310 (5746): 258–264. doi:10.1126/science.1118923. PMID 16150978.
  11. ^ a b c Planetary Defense: Double Asteroid Redirection Test (DART) Mission NASA 2017 Public Domain This article incorporates text from this source, which is in the public domain.
  12. ^ Brown, Geoff; University, Johns Hopkins. "NASA plans to test asteroid deflection technique designed to prevent Earth impact". phys.org.
  13. ^ Asteroid-deflection mission passes key development milestone 7 September 2018
  14. ^ "NASA Awards Launch Services Contract for Asteroid Redirect Test Mission". NASA. 12 April 2019. Retrieved 12 April 2019. Public Domain This article incorporates text from this source, which is in the public domain.
  15. ^ a b c "Double Asteroid Redirection Test (DART)". NASA. 28 October 2021. Retrieved 5 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  16. ^ a b "DART". dart.jhuapl.edu. Retrieved 20 May 2022.
  17. ^ Fletcher, Zachary; Ryan, Kyle; Maas, Bryan; Dickman, Joseph; Hammond, Randolph; Bekker, Dmitriy; Nelson, Tyler; Mize, James; Greenberg, Jacob; Hunt, Wendy; Smee, Stephen; Chabot, Nancy; Cheng, Andrew (6 July 2018). Design of the Didymos Reconnaissance and Asteroid Camera for OpNav (DRACO) on the double asteroid redirection test (DART). Space Telescopes and Instrumentation 2018: Optical, Infrared, and Millimeter Wave. Vol. 106981X. Austin, TX: Proceedings of SPIE 10698. doi:10.1117/12.2310136.
  18. ^ Kantsiper, Brian (2017). "The Double Asteroid Redirection Test (DART) mission electric propulsion trade". 2017 IEEE Aerospace Conference. pp. 1–7. doi:10.1109/AERO.2017.7943736. ISBN 978-1-5090-1613-6. S2CID 43072949.
  19. ^ Adams, Elena; Oshaughnessy, Daniel; Reinhart, Matthew; John, Jeremy; Congdon, Elizabeth; Gallagher, Daniel; Abel, Elisabeth; Atchison, Justin; Fletcher, Zachary; Chen, Michelle; Heistand, Christopher; Huang, Philip; Smith, Evan; Sibol, Deane; Bekker, Dmitriy; Carrelli, David (2019). "Double Asteroid Redirection Test: The Earth Strikes Back". 2019 IEEE Aerospace Conference. pp. 1–11. doi:10.1109/AERO.2019.8742007. ISBN 978-1-5386-6854-2. S2CID 195222414.
  20. ^ Talbert, Tricia (30 June 2017). "Double Asteroid Redirection Test (DART) Mission". NASA. Retrieved 21 January 2018. Public Domain This article incorporates text from this source, which is in the public domain.
  21. ^ Behind the Scenes: Inspecting DART's Roll-Out Solar Array (ROSA) Technology, retrieved 13 August 2021
  22. ^ "DART has a solar array experiment called transformational solar array on its roll out solar array panel". dart.jhuapl.edu. Archived from the original on 23 December 2019. Retrieved 13 August 2021.
  23. ^ Bray, Matthew (2020). "A Spiral Radial Line Slot Array Antenna for NASA's Double Asteroid Redirection Test (DART)". 2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting. pp. 379–380. doi:10.1109/IEEECONF35879.2020.9330400. ISBN 978-1-7281-6670-4. S2CID 231975847.
  24. ^ DART: Home page at APL Archived 2018-05-10 at the Wayback Machine DART Spacecraft APL 2017
  25. ^ "Impactor Spacecraft". NASA. 2021. Retrieved 18 February 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  26. ^ Andone, Dakin (25 July 2017). "NASA unveils plan to test asteroid defense technique". CNN. Retrieved 25 July 2017.
  27. ^ Cheng, A.F.; Michel, P.; Reed, C.; Galvez, A.; Carnelli, I. (2012). DART: Double Asteroid Redirection Test (PDF). European Planetary Science Congress 2012. EPSC Abstracts.
  28. ^ a b Michel, P.; Cheng, A.; Carnelli, I.; Rivkin, A.; Galvez, A.; Ulamec, S.; Reed, C.; AIDA Team (8 January 2015). "AIDA: Asteroid impact and deflection assessment mission under study at ESA and NASA". Spacecraft Reconnaissance of Asteroid and Comet Interiors. 1829: 6008. Bibcode:2015LPICo1829.6008M.
  29. ^ Course corrector Adam Hadhazy Aerospace America October 2017
  30. ^ NASA Pushes Through With Asteroid Deflection Mission That Could One Day Save Earth The Inquisitr 5 July 2017
  31. ^ a b Session 3: DART (PDF). 7th IAA Planetary Defense Conference. 26–30 April 2021.
  32. ^ WATCH: NASA Asteroid Redirection Test Media Briefing - Livestream, retrieved 20 May 2022
  33. ^ Rivkin, Andrew S.; Chabot, Nancy L.; Stickle, Angela M.; Thomas, Cristina A.; Richardson, Derek C.; Barnouin, Olivier; Fahnestock, Eugene G.; Ernst, Carolyn M.; Cheng, Andrew F.; Chesley, Steven; Naidu, Shantanu (25 August 2021). "The Double Asteroid Redirection Test (DART): Planetary Defense Investigations and Requirements". The Planetary Science Journal. 2 (5): 173. Bibcode:2021PSJ.....2..173R. doi:10.3847/PSJ/ac063e. ISSN 2632-3338. S2CID 237301576.
  34. ^ "DART: Asteroid - eoPortal Directory - Satellite Missions". directory.eoportal.org. Retrieved 24 November 2021.
  35. ^ a b Asteroids have been hitting the Earth for billions of years. In 2022, we hit back. Archived 2018-10-31 at the Wayback Machine Andy Rivkin, The Johns Hopkins University Applied Physics Laboratory, September 27, 2018
  36. ^ Hera mission is approved as ESA receives biggest ever budget Kerry Hebden Room Space Journal 29 November 2019
  37. ^ Kretschmar, Peter; Küppers, Michael (20 December 2018). "The CubeSat Revolution" (PDF). ESA. Retrieved 24 January 2019.
  38. ^ Cheng, Andy (15 November 2018). "DART Mission Update". ESA. Retrieved 14 January 2019.
  39. ^ "LICIACube". ASI. Retrieved 26 November 2021.
  40. ^ a b c Bergin, Chris (7 January 2019). "Hera adds objectives to planetary defense test mission". NASASpaceflight.com. Retrieved 11 January 2019.
  41. ^ The Juventas CubeSat in Support of ESA's Hera Mission to the Asteroid Didymos. Hannah R. Goldberg, Özgür Karatekin, Birgit Ritter, Alain Herique, Paolo Tortora, Claudiu Prioroc, Borja Garcia Gutierrez, Paolo Martino, Ian Carnelli. 33rd Annual AIAA/USU Conference on Small Satellites.
  42. ^ Asteroids have been hitting the Earth for billions of years. In 2022, we hit back. Archived 2018-10-31 at the Wayback Machine Andy Rivkin, The Johns Hopkins University Applied Physics Laboratory. September 27, 2018.
  43. ^ A Low Frequency Radar to Fathom Asteroids from Juventas Cubesat on HERA. Alain Herique, Dirk Plettemeier, Wlodek Kofman, Yves Rogez, Christopher Buck, and Hannah Goldberg. EPSC Abstracts. Vol. 13, EPSC-DPS2019-807-2, 2019. EPSC-DPS Joint Meeting 2019.
  44. ^ a b The Juventas CubeSat in Support of ESA's Hera Mission to the Asteroid Didymos Hannah R. Goldberg, Özgür Karatekin, Birgit Ritter, Alain Herique, Paolo Tortora, Claudiu Prioroc, Borja Garcia Gutierrez, Paolo Martino, Ian Carnelli. 33rd Annual AIAA/USU Conference on Small Satellites
  45. ^ JuRa: the Juventas Radar on Hera to fathom Didymoon Alain Herique, Dirk Plettemeier, Hannah Goldberg, Wlodek Kofman, and the JuRa Team. EPSC Abstracts. Vol.14, EPSC2020-595. doi:10.5194/epsc2020-595.
  46. ^ a b Exploration of the binary asteroid 65803 Didymos by the Hera mission. EPSC Abstracts. Vol. 13, EPSC-DPS2019-583-1, 2019. EPSC-DPS Joint Meeting 2019. 15–20 September 2019.
  47. ^ "Industry starts work on Europe's Hera planetary defence mission". 15 September 2020. Retrieved 16 June 2021.
  48. ^ Michel, Patrick; Kueppers, Michael; Sierks, Holger; Carnelli, Ian (26 April 2017). "European component of the AIDA mission to a binary asteroid: Characterization and interpretation of the impact of the DART mission" (PDF). Advances in Space Research (Article) (published 18 December 2017). 62 (8): 2261–2272. doi:10.1016/j.asr.2017.12.020. S2CID 55274187.
  49. ^ Carnelli, Ian (11 October 2017). "The Hera Mission Study" (PDF). ESA. Retrieved 11 June 2018.
  50. ^ "Spacecraft for asteroid deflection experiment ready for fueling at Vandenberg". Spaceflight Now. 20 October 2021. Retrieved 5 November 2021.
  51. ^ a b "NASA's DART Preps for Launch in First Planetary Defense Test Mission". NASA. 3 November 2021. Retrieved 24 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  52. ^ "NASA's DART Spacecraft Secured In Payload Fairing, Flight Readiness Review Complete – Double Asteroid Redirection Test (DART) Mission". blogs.nasa.gov. Retrieved 24 November 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  53. ^ Atchison, Justin A.; Ozimek, Martin T.; Kantsiper, Brian L.; Cheng, Andrew F. (1 June 2016). "Trajectory options for the DART mission". Acta Astronautica. Special Section: Selected Papers from the International Workshop on Satellite Constellations and Formation Flying 2015. 123: 330–339. Bibcode:2016AcAau.123..330A. doi:10.1016/j.actaastro.2016.03.032. ISSN 0094-5765.
  54. ^ "DART Gets Its CubeSat Companion, Its Last Major Piece". dart.jhuapl.edu. Retrieved 20 May 2022.
  55. ^ "NASA - NSSDCA - Master Catalog - Errors and Messages". nssdc.gsfc.nasa.gov. Retrieved 20 May 2022.
  56. ^ Davenport, Justin (23 November 2021). "NASA's DART asteroid redirect mission launches aboard Falcon 9 from Vandenberg". NASASpaceFlight.com. Retrieved 20 May 2022.

External links[edit]