قالب وردپرس درنا توس
Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Hubble Captures Rare Active Asteroid

Hubble Captures Rare Active Asteroid



heic1906 – Science Release

28. March 2019

Thanks to an impressive collaboration that gathers data from terrestrial telescopes, fiery surveys and space-based facilities – including the NASA / ESA Hubble Space Telescope – a rare self-destructing asteroid called 6478 Gault has been observed.

Clear images from NASA / ESA The Hubble Space Telescope has given researchers new insight into the asteroid Gault's unusual past. The object is 4-9 kilometers wide and has two narrow, comet-like tails of dirt that tell us that the asteroid slowly undergoes self-destruction. Each tail is a sign of an active event that released material into space.

Gault was discovered in 1

988. However, this observation of two debris arrays is the first indication of asteroid instability. This asteroid one of only a handful of being trapped is disintegrated by a process known as a YORP torque. When sunlight heats up an asteroid, it removes heat and momentum from the infrared radiation emanating from its warm surface. This creates a small force that can cause the asteroid to rotate faster. If this centrifugal force overcomes gravity at all, the asteroid becomes unstable. Landslides on the object can release bricks and dust into the room and leave a tail of waste as seen here with asteroid Gault.

"This self-destruction event is rare" explained Olivier Hainaut the Southern Observatory, Germany). "Active and unstable asteroids like Gault are now only discovered using new study telescopes that scan the whole sky, which means that asteroids such as Gault failing cannot escape detection."

Astronomers estimate that among the 800,000 known asteroids occupying the Asteroid Belt between Mars and Jupiter, YORP interruptions occur approximately once a year. The direct observation of this activity by the Hubble Space Telescope has given astronomers a special opportunity to study the asteroid composition. By examining the material that this unstable asteroid publishes in space, astronomers can gain insight into the planetary history of the Solar System's early years.

Understanding the nature of this active and self-destructive object has been a collaboration effort involving researchers and facilities around the world. The Asteroid Burning Tail was first registered by the University of Hawaii in NASA ATLAS (Asteroid Terrestrial Impact Last Alert System) telescopes on the Hawaiian Islands on January 5, 2019. After reviewing the archive data of ATLAS and UH / NASA Pan-STARRS (Panoramic Survey Telescope and Rapid Response System) it was found that the object's larger tail tail had been observed earlier in December 2018. Shortly after, in January 2019 another shorter tail was seen by various telescopes, including Isaac Newton, William Herschel and ESA OGS. telescopes in La Palma and Tenerife, Spain; The Himalaya Chandra Telescope in India and CFHT in Hawaii. Subsequent analysis of these observations pointed out that the two incidents that produced these debris paths occurred on October 28 and December 30, 2018, respectively. These tails will only be visible for a few months, after which the dust will have spread in the interplanetary room.

Subsequent observations were then made by various terrestrial telescopes. These data were used to derive a two hour rotational period for Gault, which is very close to the critical rate at which the material begins to tumble and slide over the asteroid surface before it enters the space.

"Gault is the best" smoking gun "example of a fast rotator right at the two-hour border explained lead author Jan Kleyna (University of Hawaii in the United States) . "It could have been on the brink of instability for 10 million years. Even a slight disturbance as a small impact from a stone may have triggered the latest outbreaks. "

Hubble's sharp imaging gave valuable details on the asteroid's activity. From the narrow width of the streaming stars, scientists deduced that the release of the material took place in short episodes lasting from a few hours to a few days. Excess dust in the immediate vicinity of the asteroid concluded that asteroid activity was not caused by a collision with another massive object, and researchers hope that further observations will provide even more insight into this rare and curious object.

Team results are has been accepted for publication in The Astrophysical Journal Letters.

More Information

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The research group's work is presented in the scientific document "The sporadic activity by Gault: A YORP-powered event "which will be published in ] The Astrophysical Journal Letters .

ATLAS (Asteroid Terrestrial-Impact Last Alert System) is an asteroid-effect alert system developed by the University of Hawaii in and funded by NASA. It consists of two telescopes, 100 miles apart, which automatically scans the whole sky several times each night looking for moving objects.

The international team of astronomers in this study consists of Jan T. Kleyna (University of Hawaii in the Institute for Astronomy, USA), Olivier R. Hainaut (European Southern Observatory, Germany), Karen J. Meech (University of Hawaii in the Institute for Astronomy, USA), Henry H. Hsieh (Planetary Science Institute, USA, and Academia Sinica Institute of Astronomy and Astrophysics, Taiwan), Alan Fitzsimmons (Queen's University Belfast Astrophysics Research Center, UK), Marco Micheli (European Space Agency Near Earth's Object Coordination Center, Italy, and the National Institute for Astrophysics – Osservatorio Astronomico di Roma, Italy), Jacqueline V Keane (University of Hawaii in the Institute for Astronomy, USA), Larry Denneau (University of Hawaii & # 39; 39; in the Institute for Astronomy, USA), John Tonry (University of Hawaii in the Institute for Astronomy, USA), Aren He inze (University of Hawaii in the Institute for Astronomy, USA), Bhuwan C. Bhatt ( Indian Inst itute for Astrophysics, India), Devendra K. Sahu (Indian Institute of Astrophysics, India),

Detlef Koschny Space Research and Technology Center, Holland & Near Earth Object Coordination Center, Italy and Technical University of Munich, Germany), Ken W. Smith (Queen's University Belfast Astrophysics Research Center, UK), Harald Ebeling (University of Hawaii in the Institute for Astronomy, USA), Robert Weryk (University of Hawaii in the Institute for Astronomy, USA), Heather Flewelling (University of Hawaii in the Institute for Astronomy, USA) and Richard J. Wainscoat (University of Hawaii in the Institute for Astronomy, USA).

Image Credit: NASA, ESA, NASA, ESA, K. Meech and J. Kleyna (University of Hawaii), O. Hainaut (European Southern Observatory), L. Calçada

Links

Contacts

Jan Kleyna
Department of Astronomy
Honolulu, HI, USA
Tel: +1 808 956-0797
Email: kleyna@hawaii.edu

Olivier Hainaut
European Southern Observatory
Garching bei München, Germany
Tel: +49 89 3200 6752
Email: ohainaut@eso.org

Dr. Karen Meech
Department of Astronomy
Honolulu, HI, USA
Tel: + 1-808-956-6828
Email: meech@ifa.hawaii.edu

Bethany Downer
ESA / Hubble, Public Information Officer
Garching bei München, Germany
Email: bethany.downer@partner.eso.org


Source link