![]() ![]() A commercial off-the-shelf CMOS detector was used instead of a custom charge-coupled device in LORRI, as DRACO did not require the extreme low-light performance demanded of LORRI during New Horizons ' Pluto flyby. The detector records the wavelength range from 0.4 to 1 micron (visible and near infrared). The detector used in the camera was a CMOS image sensor measuring 2,560 × 2,160 pixels. The instrument had a mass of 8.66 kg (19.1 lb). The spatial resolution of the images taken immediately before the impact are expected to be around 20 centimeters per pixel. The optical part of DRACO was a Ritchey-Chrétien telescope equipped with telephoto lens with a field of view of 0.29° and a focal length of 2.6208 m (f/12.60). DRACO was based on the Long Range Reconnaissance Imager (LORRI) onboard New Horizons spacecraft, and supported autonomous navigation to impact the asteroid's moon at its center. Camera ĭART's navigation sensors included a sun sensor, a star tracker called SMART Nav software (Small-body Maneuvering Autonomous Real Time Navigation), and a 20 cm (7.9 in) aperture camera called Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO). The spacecraft cost US$330 million by the time it collided with Dimorphos in 2022. The DART spacecraft was an impactor with a mass of 610 kg (1,340 lb) that hosted no scientific payload and had sensors only for navigation. On impact, Deep Impact released 19 gigajoules of energy (the equivalent of 4.8 tons of TNT), and excavated a crater up to 150 m (490 ft) wide. Satellite impact on a small solar system body had already been implemented once, by NASA's 372 kg (820 lb) Deep Impact space probe's impactor spacecraft and for a completely different purpose (analysis of the structure and composition of a comet). On 11 April 2019, NASA announced that a SpaceX Falcon 9 would be used to launch DART. In June 2017, NASA approved a move from concept development to the preliminary design phase, and in August 2018 the start of the final design and assembly phase of the mission. Live monitoring of the DART impact thus had to be obtained from ground-based telescopes and radar. The AIM orbiter was however canceled, then replaced by Hera which plans to start observing the asteroid four years after the DART impact. ![]() ![]() DART would then kinetically impact the asteroid's moon on 26 September 2022, during a close approach to Earth. AIM would have orbited the larger asteroid to study its composition and that of its moon. Under that proposal, the European spacecraft, AIM, would have launched in December 2020, and DART in July 2021. NASA and the European Space Agency (ESA) started with individual plans for missions to test asteroid deflection strategies, but by 2015, they struck a collaboration called AIDA (Asteroid Impact and Deflection Assessment) involving two separate spacecraft launches that would work in synergy. The Italian Space Agency contributed LICIACube, a CubeSat which photographed the impact event, and other international partners, such as the European Space Agency (ESA), and Japan Aerospace Exploration Agency (JAXA), are contributing to related or subsequent projects. The project was funded through NASA's Planetary Defense Coordination Office, managed by NASA's Planetary Missions Program Office at the Marshall Space Flight Center, and several NASA laboratories and offices provided technical support. ĭART is a joint project between NASA and the Johns Hopkins Applied Physics Laboratory. DART's success in deflecting Dimorphos was due to the momentum transfer associated with the recoil of the ejected debris, which was substantially larger than that caused by the impact itself. Launched from Earth on 24 November 2021, the DART spacecraft successfully collided with Dimorphos on 26 September 2022 at 23:14 UTC and shortened its orbit by 32 minutes, greatly in excess of the pre-defined success threshold of 73 seconds. The selected target asteroid, Dimorphos, is a minor-planet moon of the asteroid Didymos neither asteroid poses an impact threat to Earth. It was designed to assess how much a spacecraft impact deflects an asteroid through its transfer of momentum when hitting the asteroid head-on. Double Asteroid Redirection Test ( DART) was a NASA space mission aimed at testing a method of planetary defense against near-Earth objects (NEOs). ![]()
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