Saturday , February 4 2023

Festive asteroid with NASA radars – ScienceDaili


The approaching December 2018 with the large asteroid 2003 SD220 enabled astronomers to have the extraordinary ability to get detailed radar images of the surface and shape of the object and to improve the understanding of its orbit.

The asteroid will fly safely next to Earth on Saturday, December 22, at a distance of about 2.8 million kilometers. It will be the closest approach to the asteroid in more than 400 years, and the closest will be until 2070, when the asteroid will safely come closer to Earth.

Radar images reveal an asteroid of at least one mile (1.6 kilometers) in length and a shape similar to that exposed part of a nile horse that runs in the river. They were received from 15 to 17 December by coordinating observations with NASA's 70-meter antenna in the Goldstone Deep Space Complek complex in California, a green bank telescope on the west coast of the National Science Foundation, 330 meters long. Virginia and the Arecibo Observatory of 305 meters in Puerto Rico.

The Green Bank Telescope was a receiver for powerful microwave signals transmitted by either planetary radar in the Goldstone or NASA funded by NASA in the so-called "radical radar configuration". The use of a single transmission telescope, and the other for receiving can give much more detail than a single telescope, and it is an invaluable technique for obtaining radar images of close, slowly rotating asteroids such as this.

"Radar images achieve an unprecedented level of detail and can be compared to those derived from aircraft flying," said Lance Benner of the Jet Propulsion Laboratory in Pasadena, California, and a scientist who led the observations from Goldstone. "The most prominent surface feature is the prominent ridge that appears to be wrapped around the asteroid near one end. The ridge extends to about 330 feet. [100 meters] above the surrounding terrain. There are many small bright spots in the data and can be reflections of stones. The images also show a group of dark, circular features near the right edge that can be craters. "

The images confirm what was seen in earlier measurements of the "light curve" of sunlight reflected by asteroids and earlier radar images by Arecibo: 2003 SD220 has an exceptionally slow rotation period of about 12 days. It also has something that looks like a complex rotation that is somewhat analogous to a bad throw of football. Known as the "non-main axis" rotation, it is unusual in the asteroid near Earth, most of which revolve around its shortest axis.

With a resolution of only 12 feet (3.7 meters) per pixel, the detail of these images is 20 times finer than the one obtained during the previous close approach of the Earth's asteroid three years ago, which was at a greater distance. New radar data will provide important limitations in the asteroid density distribution – information that is available on a very small number of asteroids near the Earth.

"This year, with our knowledge of the slow rotation of the 2003 SD220, we were able to plan a large sequence of radar images using the largest radio telescopes in one country," said Patrick Tailor, a senior scientist at the University Space Research Association. USRA) at the Lunar and Planet Institute (LPI) in Houston.

"The new details we discovered, all the way to the 2003 SD220 geology, will allow us to reconstruct its shape and state of rotation, as it did with Bennu, the OSIRIS-REk mission," said Edgard Rivera-Valentin, USRA a scientist in LPI. "A detailed reconstruction of the shape allows us to better understand how these small bodies formed and evolved over time."

Patrick Tailor was leading the radical observation with the Green Bank Observatory, the home of the Green Banking Telescope, the largest fully manageable radio telescope in the world. Rivera-Valentin will lead the reconstruction of the 2003 SD220 format and lead the Arecibo Observatory.

Asteroid 2003 SD220 was discovered on 29 September 2003 by astronomers from the Lovell Object Observatory (LONEOS) in Flagstaff, Arizona – a NASA-funded Neo-Nuclear Research Project (NEO). longer in work. It is classified as a "potentially dangerous asteroid" due to its size and close access to the Earth's orbit. However, these radar measurements further enhance the understanding of the orbits SD220 in 2003, confirming that it does not represent a future threat to the Earth.

Planets of planetary radars Arecibo, Goldstone and USRA are funded through NASA's Earth Observation Program near the Planetary Defense Coordination Office (PDCO), which manages the Planetary Defense Program of the Agency. Arecibo Observatory is a facility of the National Science Foundation, which operates on the basis of a cooperation agreement between the University of Central Florida, Iang Enterprises and Universidad Metropolitan. GBO is an institution of the National Science Foundation, which operates on the basis of an agreement on the cooperation of Associate Universities, Inc.

JPL hosts the Earth Exploration Facility near Earth (CNEOS) for NASA's Earth Observation Program.

More information about CNEOS, asteroids, and objects near the Earth can be found at:

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For more information about NASA's Planetary Defense Coordinating Office, visit:

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More information on the Arecibo Observatory of the National Science Foundation can be found at:

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For news and updates of asteroids and comets, follow the AsteroidVatch on Twitter: / AsteroidVatch

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