Belgian-born astronomer and professor
Jean-Luc Margot (born 1969) is a Belgian-born astronomer and a UCLA professor with expertise in planetary sciences and SETI .
Career
Margot has discovered and studied several binary asteroids with radar and optical telescopes. His discoveries include (87) Sylvia I Romulus , (22) Kalliope I Linus , S/2003 (379) 1 , (702) Alauda I Pichi üñëm , and the binary nature of (69230) Hermes .
In 2000, he obtained the first images of binary near-Earth asteroids and described formation of the binary by a spin-up process.[ 1] [ 2] Margot and his research group have studied the influence of sunlight on the orbits and spins of asteroids, the Yarkovsky and YORP effects.[ 3] [ 4] [ 5]
In 2007, Margot and collaborators determined that Mercury has a molten core from the analysis of small variations in the rotation rate of the planet.[ 6] [ 7] These observations also enabled a measurement of the size of the core based on a concept proposed by Stan Peale .[ 8] [ 9]
In 2012, Margot and graduate student Julia Fang analyzed Kepler space telescope data to infer the architecture of planetary systems.[ 10] They described planetary systems as "flatter than pancakes."[ 11] They also showed that many planetary systems are dynamically packed.[ 12]
Margot proposed an extension to the IAU definition of planet that applies to exoplanets .[ 13] [ 14]
Between 2006 and 2021, Margot and collaborators measured the spin of Venus with a radar speckle tracking technique. They measured the orientation and precession of the spin axis. They also measured the duration of the length of day and the amplitude of length-of-day variations , which they attribute to transfer of momentum between the atmosphere and the solid planet.[ 15] [ 16]
Since 2016, he has conducted searches for technosignatures using large radio telescopes with UCLA students.[ 17] [ 18] Volunteers can contribute to SETI through the "Are we alone in the universe? " citizen science collaboration.[ 19]
Honors and awards
Margot was awarded the H. C. Urey Prize by the American Astronomical Society in 2004.[ 20] The asteroid 9531 Jean-Luc is named after him.[ 21]
References
^ "Some Asteroids Have Astronomers Seeing Double" . JPL press release . 11 April 2002. Archived from the original on 17 July 2012. Retrieved 10 November 2015 .
^ Margot, Jean-Luc; et al. (2002). "Binary Asteroids in the Near-Earth Object Population". Science . 296 (5572): 1445– 1448. Bibcode :2002Sci...296.1445M . doi :10.1126/science.1072094 . PMID 11951001 . S2CID 8768432 .
^ "Prediction Proved: Light Speeds Up an Asteroid as it Spins" . The New York Times . 13 March 2007.
^ Taylor, Patrick; et al. (2007). "Spin Rate of Asteroid (54509) 2000 PH5 Increasing due to the YORP Effect" . Science . 316 (5822): 274– 277. Bibcode :2007Sci...316..274T . doi :10.1126/science.1139038 . PMID 17347415 . S2CID 29191700 . .
^ Greenberg, Adam H.; Margot, Jean-Luc; Verma, Ashok K.; Taylor, Patrick A.; Hodge, Susan E. (7 February 2020). "Yarkovsky Drift Detections for 247 Near-Earth Asteroids" . The Astronomical Journal . 159 (3): 92. arXiv :1708.05513 . Bibcode :2020AJ....159...92G . doi :10.3847/1538-3881/ab62a3 . S2CID 119502545 .
^ "Mercury's spin reveals molten, not solid core" . Reuters . 3 May 2007.
^ Margot, Jean-Luc; et al. (2007). "Large longitude libration of Mercury reveals a molten core". Science . 316 (5825): 710– 714. Bibcode :2007Sci...316..710M . doi :10.1126/science.1140514 . PMID 17478713 . S2CID 8863681 .
^ Peale, S. J. (1976). "Does Mercury have a molten core?". Nature . 262 (5571): 765– 766. Bibcode :1976Natur.262..765P . doi :10.1038/262765a0 . S2CID 4210179 .
^ Margot, Jean-Luc; et al. (2012). "Mercury's moment of inertia from spin and gravity data" . Journal of Geophysical Research . 117 : n/a. Bibcode :2012JGRE..117.0L09M . doi :10.1029/2012JE004161 .
^ Fang, Julia; Margot, Jean-Luc (2012). "Architecture of Planetary Systems Based on Kepler Data: Number of Planets and Coplanarity". The Astrophysical Journal . 761 (2): 92. arXiv :1207.5250 . Bibcode :2012ApJ...761...92F . doi :10.1088/0004-637X/761/2/92 . ISSN 0004-637X . S2CID 20234144 .
^ "Most Alien Solar Systems Are 'Flatter Than Pancakes' " . Space.com . 15 October 2012.
^ Fang, Julia; Margot, Jean-Luc (2013). "Are Planetary Systems Filled to Capacity? A Study Based on Kepler Results". The Astrophysical Journal . 767 (2): 115. arXiv :1302.7190 . Bibcode :2013ApJ...767..115F . doi :10.1088/0004-637X/767/2/115 . ISSN 0004-637X . S2CID 53706876 .
^ "Why we need a new definition of the word 'planet' " . Los Angeles Times . 14 November 2015.
^ Margot, Jean-Luc (1 December 2015). "A Quantitative Criterion for Defining Planets". The Astronomical Journal . 150 (6): 185. arXiv :1507.06300 . Bibcode :2015AJ....150..185M . doi :10.1088/0004-6256/150/6/185 . S2CID 51684830 .
^ Crockett, Christopher. "How long is a day on Venus? Scientists crack mysteries of our closest neighbor" . phys.org .
^ Margot, Jean-Luc; Campbell, Donald B.; Giorgini, Jon D.; Jao, Joseph S.; Snedeker, Lawrence G.; Ghigo, Frank D.; Bonsall, Amber (July 2021). "Spin state and moment of inertia of Venus". Nature Astronomy . 5 (7): 676– 683. arXiv :2103.01504 . Bibcode :2021NatAs...5..676M . doi :10.1038/s41550-021-01339-7 . S2CID 232092194 .
^ "Researchers Just Scanned 14 Worlds From the Kepler Mission for "Technosignatures", Evidence of Advanced Civilizations" . Universe Today . 15 February 2018.
^ Margot, Jean-Luc; Li, Megan G.; Pinchuk, Pavlo; Myhrvold, Nathan; Lesyna, Larry; et al. (1 November 2023). "A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15–1.73 GHz" . The Astronomical Journal . 166 (5): 206. arXiv :2308.02712 . Bibcode :2023AJ....166..206M . doi :10.3847/1538-3881/acfda4 .
^ "UCLA is asking for the public's help in finding signs of extraterrestrial intelligence" . Los Angeles Times . 15 February 2023.
^ "Harold C. Urey Prize in Planetary Science" . Division of Planetary Sciences of the American Astronomical Society . Retrieved 11 December 2021 .
^ "Small Body Orbital Elements 9531 Jean-Luc (1981 QK)" . JPL. Retrieved 11 December 2021 .
External links
International National Academics