Deimos (moon)
Deimos (or Mars II) is the smaller moon of Mars. Its name comes from the Greek word for terror. Its orbital period is 30.3 hours, which is 1.263 days.
Deimos is only 15 kilometers in diameter. It is covered with craters, as Earth's moon and other bodies without an atmosphere are.
Discovery and naming
Deimos was discovered by Asaph Hall at the United States Naval Observatory in Washington, D.C. on 12 August 1877.[1]
It is named after the god Deimos in Greek mythology, who was one of Mars' sons, and means Panic.
Physical characteristics
Deimos is not spherical with triaxial dimensions of 15 × 12.2 × 11 km.[2] Deimos is made up of rock rich in carbonaceous material. It is has lots of craters.[3] Escape velocity from Deimos is 5.6 m/s.[4] The apparent magnitude of Deimos is 12.45.[5]
Exploration
The Soviet Phobos program sent two probes to Phobos. In case Phobos 1 succeeded, Phobos 2 could have been sent to Deimos. Both probes launched successfully in July 1988.
In 1997 and 1998, the proposed Aladdin mission was selected. The plan was to visit both Phobos and Deimos, and launch projectiles at the satellites. The probe would collect the dust kicked into space as it made a slow flyby. These samples would be returned to Earth for study three years later.[6]
Also, the sample-return mission called Gulliver to Deimos, in bringing 1 kilogram (2.2 pounds) of material from Deimos to Earth.[7]
Another concept of sample-return mission from Phobos and Deimos is OSIRIS-REx 2, which would use heritage from the first OSIRIS-REx.[8]
In March 2014, a mission was proposed to place an orbiter on Mars orbit by 2021 and study Phobos and Deimos. It is called Phobos And Deimos & Mars Environment (PADME).[9][10]
Deimos (moon) Media
Asaph Hall, discoverer of Deimos.
The two named craters on Deimos
Orbits of Phobos and Deimos (to scale)
Curiosity's view of the Mars moons: Phobos passing in front of Deimos in real-time (video-gif, 1 August 2013)
Deimos transits the Sun – as viewed by the Mars rover Opportunity (4 March 2004)
Deimos and Phobos as seen from Mars, compared to the Moon as seen from Earth (in angular sizes)
References
- ↑ Campbell, W. W. (1918). "The Beginning of the Astronomical Day". Publications of the Astronomical Society of the Pacific. 30 (178): 358. Bibcode:1918PASP...30..358C. doi:10.1086/122784. ISSN 0004-6280. S2CID 121676646.
- ↑ "Deimos, moon of Mars - The Solar System on Sea and Sky". www.seasky.org. Retrieved 2020-10-25.
- ↑ Busch, Michael W.; Ostro, Steven J.; Benner, Lance A.M.; Giorgini, Jon D.; Magri, Christopher; Howell, Ellen S.; Nolan, Michael C.; Hine, Alice A.; Campbell, Donald B. (2007). "Arecibo radar observations of Phobos and Deimos". Icarus. 186 (2): 581–584. Bibcode:2007Icar..186..581B. doi:10.1016/j.icarus.2006.11.003.
- ↑ "Solar System Exploration: Planets: Mars: Moons: Deimos: Facts & Figures". 2012-10-12. Archived from the original on 2012-10-12. Retrieved 2020-10-25.
- ↑ "Planetary Satellite Physical Parameters". ssd.jpl.nasa.gov. Retrieved 2020-10-25.
- ↑ Barnouin-Jha, O.S.; Cheng, A.F.; von Mehlem, U.I. (1999). "Aladdin: Sample return from the moons of Mars". 1999 IEEE Aerospace Conference. Proceedings (Cat. No.99TH8403). Vol. 1. Snowmass at Aspen, CO, USA: IEEE. pp. 403–412 vol.1. doi:10.1109/AERO.1999.794346. ISBN 978-0-7803-5425-8. S2CID 129101577.
- ↑ Dr. Britt – The Gulliver Mission: Sample Return from Deimos (PDF).
- ↑ Elifritz, T. L. (2012-06-01). "OSIRIS-REx II to Mars --- Mars Sample Return from Phobos and Deimos". Concepts and Approaches for Mars Exploration. 1679: 4017. Bibcode:2012LPICo1679.4017E.
- ↑ Phobos And Deimos & Mars Environment (PADME): A LADEE-Derived Mission to Explore Mars's Moons and the Martian Orbital Environment (PDF).
- ↑ Reyes, Tim (2014-10-01). "Making the Case for a Mission to the Martian Moon Phobos". Universe Today. Retrieved 2020-10-25.