596 Scheila
Encyclopedia
596 Scheila is a main-belt
asteroid
and main-belt comet
orbiting the Sun
. It was discovered on 21 February 1906 by August Kopff
from Heidelberg
. Kopff named the asteroid after a female English student with whom he was acquainted.
On December 11.4 2010, Steve Larson of the Catalina Sky Survey
detected a comet-like appearance to asteroid Scheila: it displayed a "coma
" of about magnitude
13.5. Inspection of archival Catalina Sky Survey observations showed the activity was triggered between 2010 November 11 and December 3. Imaging with the 2-meter Faulkes Telescope North
revealed a linear tail in the anti-sunward direction and an orbital tail, indicative of larger slower particles.
When first detected it was unknown what drove the ejecta plumes. Scheila's gravity is too large for electrostatics
to launch dust. Cometary outgassing
could not be ruled out until detailed spectroscopic
observations indicated the absence of gas in Scheila's plumes. Observations by the Hubble Space Telescope
and the Swift Gamma Ray Burst Mission's
UV-optical telescope make it most likely that Scheila was impacted
at ~5 km/s by a previously unknown asteroid ~35 meters in diameter.
In 2010, the Hubble Space Telescope
observed the aftermath of a catastrophic collision that destroyed the much smaller asteroid P/2010 A2
. Each asteroid the size of Scheila might be hit by an impactor 10–100 meters in diameter approximately every 1000 years, so with 200 asteroids of this size or bigger in the asteroid belt, we can observe a collision as often as every 5 years.
Scheila last came to perihelion
on 2007 May 20 and will not come to perihelion again until 2012 May 19.
Asteroid belt
The asteroid belt is the region of the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets...
asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
and main-belt comet
Main-belt comet
Main-belt comets are bodies orbiting within the main asteroid belt which have shown cometary activity during part of their orbit. The Jet Propulsion Laboratory defines a main-belt asteroid as an asteroid with a semi-major axis of more than 2 AU but less than 3.2 AU, and a perihelion of no less...
orbiting the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
. It was discovered on 21 February 1906 by August Kopff
August Kopff
August Kopff was a German astronomer who discovered several comets and asteroids. He worked in Heidelberg, then joined the Humboldt University of Berlin where he became the Director of the Institute for Astronomical Calculation.He discovered some comets, including periodic comet 22P/Kopff and the...
from Heidelberg
Heidelberg
-Early history:Between 600,000 and 200,000 years ago, "Heidelberg Man" died at nearby Mauer. His jaw bone was discovered in 1907; with scientific dating, his remains were determined to be the earliest evidence of human life in Europe. In the 5th century BC, a Celtic fortress of refuge and place of...
. Kopff named the asteroid after a female English student with whom he was acquainted.
On December 11.4 2010, Steve Larson of the Catalina Sky Survey
Catalina Sky Survey
Catalina Sky Survey is a project to discover comets and asteroids, and to search for Near-Earth objects. More specifically, to search for potentially hazardous asteroids , that may pose a threat of impact.-Mission:...
detected a comet-like appearance to asteroid Scheila: it displayed a "coma
Coma (cometary)
frame|right|The [[153P/Ikeya-Zhang|comet Ikeya-Zhang]] exhibiting a bright, condensed coma In astronomy, a coma is the nebulous envelope around the nucleus of a comet. It is formed when the comet passes close to the Sun on its highly elliptical orbit; as the comet warms, parts of it sublimate...
" of about magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
13.5. Inspection of archival Catalina Sky Survey observations showed the activity was triggered between 2010 November 11 and December 3. Imaging with the 2-meter Faulkes Telescope North
Faulkes Telescope North
The Faulkes Telescope North is a clone of the Liverpool Telescope, and is located at Haleakala Observatory in the U.S. state of Hawaii.The telescope is owned and operated by LCOGT. This telescope and its sister telescope Faulkes Telescope South are used by research and education groups across the...
revealed a linear tail in the anti-sunward direction and an orbital tail, indicative of larger slower particles.
When first detected it was unknown what drove the ejecta plumes. Scheila's gravity is too large for electrostatics
Electrostatics
Electrostatics is the branch of physics that deals with the phenomena and properties of stationary or slow-moving electric charges....
to launch dust. Cometary outgassing
Outgassing
Outgassing is the release of a gas that was dissolved, trapped, frozen or absorbed in some material. As an example, research has shown how the concentration of carbon dioxide in the Earth's atmosphere has sometimes been linked to ocean outgassing...
could not be ruled out until detailed spectroscopic
Spectroscopy
Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
observations indicated the absence of gas in Scheila's plumes. Observations by the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...
and the Swift Gamma Ray Burst Mission's
Swift Gamma-Ray Burst Mission
The Swift Gamma-Ray Burst Mission consists of a robotic spacecraft called Swift, which was launched into orbit on 20 November 2004, 17:16:00 UTC on a Delta II 7320-10C expendable launch vehicle. Swift is managed by the NASA Goddard Space Flight Center, and was developed by an international...
UV-optical telescope make it most likely that Scheila was impacted
Impact event
An impact event is the collision of a large meteorite, asteroid, comet, or other celestial object with the Earth or another planet. Throughout recorded history, hundreds of minor impact events have been reported, with some occurrences causing deaths, injuries, property damage or other significant...
at ~5 km/s by a previously unknown asteroid ~35 meters in diameter.
In 2010, the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...
observed the aftermath of a catastrophic collision that destroyed the much smaller asteroid P/2010 A2
P/2010 A2
P/2010 A2 is a small Solar System body that displayed characteristics of both an asteroid and a comet, and thus, was initially given a cometary designation. Since it has the orbit of a main-belt asteroid and showed the tail of a comet, it was listed as a main-belt comet...
. Each asteroid the size of Scheila might be hit by an impactor 10–100 meters in diameter approximately every 1000 years, so with 200 asteroids of this size or bigger in the asteroid belt, we can observe a collision as often as every 5 years.
Scheila last came to perihelion
Apsis
An apsis , plural apsides , is the point of greatest or least distance of a body from one of the foci of its elliptical orbit. In modern celestial mechanics this focus is also the center of attraction, which is usually the center of mass of the system...
on 2007 May 20 and will not come to perihelion again until 2012 May 19.
External links
- Orbital simulation from JPL (Java) / Ephemeris
- Comet-like appearance of (596) Scheila (Remanzacco Observatory)
- What's up with Scheila (596) (AARTScope Blog)
- Joseph Brimacombe animation on flckr
- (596) Scheila 2010-12-12 10:45:39UT (cbellh47 @ flckr)
- (596) Scheila by Rolando Ligustri (CAST-Italia)
- Comet-like appearance of (596) Scheila (MPML at Yahoo Groups)
- Asteroid 596 Scheila "Outburst" (Unmanned SpaceFlight)
- asteroid 596 Scheila goes cometary! (Cloudy Nights)
- UA Catalina Sky Survey Discovers Possible Extinct Comet (University of Arizona 2010 Dec 21)
- NASA's Swift and Hubble Probe Asteroid Collision Debris (04.28.11)
- Near Infrared Observations of Comet-Like Asteroid (596) Scheila (arXivArXivThe arXiv |Chi]], χ) is an archive for electronic preprints of scientific papers in the fields of mathematics, physics, astronomy, computer science, quantitative biology, statistics, and quantitative finance which can be accessed online. In many fields of mathematics and physics, almost all...
:1107.3845 : 19 Jul 2011) - Interpretation of (596) Scheila's Triple Dust Tails (arXivArXivThe arXiv |Chi]], χ) is an archive for electronic preprints of scientific papers in the fields of mathematics, physics, astronomy, computer science, quantitative biology, statistics, and quantitative finance which can be accessed online. In many fields of mathematics and physics, almost all...
:1110.1150 : 6 Oct 2011) - The cause of asteroid Scheila’s outburst (EPSC-DPS JOINT MEETING 2011 PRESS NOTICE)
