2008 KV42
Encyclopedia
, nicknamed Drac is a trans-Neptunian object
Trans-Neptunian object
A trans-Neptunian object is any minor planet in the Solar System that orbits the Sun at a greater distance on average than Neptune.The first trans-Neptunian object to be discovered was Pluto in 1930...

 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...

 in retrograde motion (backwards) and almost perpendicular to the ecliptic
Ecliptic
The ecliptic is the plane of the earth's orbit around the sun. In more accurate terms, it is the intersection of the celestial sphere with the ecliptic plane, which is the geometric plane containing the mean orbit of the Earth around the Sun...

: it has a 104-degree inclination
Inclination
Inclination in general is the angle between a reference plane and another plane or axis of direction.-Orbits:The inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit...

. This odd orbit suggests that may have been perturbed inwards from the Oort cloud
Oort cloud
The Oort cloud , or the Öpik–Oort cloud , is a hypothesized spherical cloud of comets which may lie roughly 50,000 AU, or nearly a light-year, from the Sun. This places the cloud at nearly a quarter of the distance to Proxima Centauri, the nearest star to the Sun...

. Comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...

s are thought to originate from the Oort cloud and this discovery may finally show how they transition from the Oort cloud to become objects like Halley's Comet.

The orbits of trans-Neptunian objects provide important clues as to how the outer Solar System took form and evolved. Discoveries of new classes of objects have led to fresh insights into the early history of the Solar System, challenging accepted theories. The discovery of , the first-ever object in this region to be detected with a retrograde
Retrograde and direct motion
Apparent retrograde motion is the motion of a planetary body in a direction opposite to that of other bodies within its system as observed from a particular vantage point...

 orbit, promises to do just that.

"Although we've been specifically looking for highly-tilted trans-Neptunians for some time now, we didn't expect to find a retrograde one", said Dr. JJ Kavelaars of the National Research Council of Canada
National Research Council of Canada
The National Research Council is an agency of the Government of Canada which conducts scientific research and development.- History :...

. "A number of theories on the formation of the outer Solar System have suggested that such things might be out there, but observational searches for them are very difficult."

Part of the difficulty is that these objects are extremely rare. Despite having surveyed most of the northern sky for bright objects of this type, astronomers have found only one other that might belong to the same class as . Discovered six years ago by the Deep Ecliptic Survey
Deep Ecliptic Survey
The Deep Ecliptic Survey is a project to find Kuiper belt objects , using the facilities of the National Optical Astronomy Observatory .The principal investigator is Bob Millis....

, has an orbit on a 77-degree tilt.

One of the great frustrations for researchers looking into the region beyond Neptune
Neptune
Neptune is the eighth and farthest planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times...

 has been trying to pin down the source regions for various comet types. Finding objects that provide a link between the source region and the observed comet population is an enormous help in choosing between the source regions, greatly clarifying our understanding of the formation of the outer Solar System.

This discovery was made using the Canada-France-Hawaii Telescope
Canada-France-Hawaii Telescope
The Canada–France–Hawaii Telescope is located near the summit of Mauna Kea mountain on Hawaii's Big Island at an altitude of 4,204 meters , and is one of the observatories that comprise the Mauna Kea Observatory...

 in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, with follow-up observations provided by the MMT telescope in Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

, the Cerro Tololo Inter-American Observatory
Cerro Tololo Inter-American Observatory
The Cerro Tololo Inter-American Observatory is a complex of astronomical telescopes and instruments located at 30.169 S, 70.804 W, approximately 80 km to the East of La Serena, Chile at an altitude of 2200 metres. The complex is part of the National Optical Astronomy Observatory along with Kitt...

 (CTIO) 4-metre telescope in Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, and the Gemini South telescope, also in Chile, of Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

's Gemini Observatory
Gemini Observatory
The Gemini Observatory is an astronomical observatory consisting of two telescopes at sites in Hawai‘i and Chile. Together, the twin Gemini telescopes provide almost complete coverage of both the northern and southern skies...

. The discovery team consists of scientists in Canada, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

, and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

.

"Having quick access to the MMT and Gemini South telescopes, via the generous support of the observers at MMT and the Canadian Director of Gemini South, Jean‑René Roy, was a huge help here. Given the highly unusual orbit, the object would have been lost without the critical tracking contribution of these large telescopes," said Dr. Brett Gladman, an astronomy professor and Canada Research Chair at the University of British Columbia
University of British Columbia
The University of British Columbia is a public research university. UBC’s two main campuses are situated in Vancouver and in Kelowna in the Okanagan Valley...

.

The discovery team is currently planning follow-up observations of to pin down its orbit with greater precision. The exciting work of unravelling the archaeological information trapped in the orbit of this highly exceptional member of the trans-Neptunian population can then begin.

The discovery of was announced at the 10th triennial "Asteroids, Comets and Meteors" meeting in Baltimore
Baltimore
Baltimore is the largest independent city in the United States and the largest city and cultural center of the US state of Maryland. The city is located in central Maryland along the tidal portion of the Patapsco River, an arm of the Chesapeake Bay. Baltimore is sometimes referred to as Baltimore...

 and via the Minor Planet Electronic Circular
Minor Planet Electronic Circular
The Minor Planet Electronic Circulars are published by the Minor Planet Center. They generally contain positional observations and orbits of unusual minor planets and all comets. Monthly lists of observable unusual objects, observable distant objects, observable comets and the critical list of...

 (MPEC) 2008-O02 on July 16, 2008, and International Astronomical Union
International Astronomical Union
The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

 electronic circular (IAUC) 8960 on July 18, 2008. Recent observations taken with the Canada-France-Hawaii Telescope have further refined our knowledge of the orbit, securing this as a possible link between the inner Oort cloud and the Halley-type comets.

With a semi-major axis
Semi-major axis
The major axis of an ellipse is its longest diameter, a line that runs through the centre and both foci, its ends being at the widest points of the shape...

 of 46±5 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....

, was discovered while at a distance of 32 AU and has a perihelion at roughly the distance of Uranus
Uranus
Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus , the father of Cronus and grandfather of Zeus...

.

External links

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