庫伯帶天體

存在於海王星之外,遙遠的外太陽系,據推測可能有數十萬個小天體,圍繞著太陽系的最邊緣地帶,

此為庫伯帶天體,冥王星很可能也是庫伯帶天體之一,但尚未証實。庫伯帶天體因距離遠,體積小,

故已發現的天體不多,目前科學家推測,大部份的彗星可能源自於此,以下資料引自 SEDS HST

[Image of KBComets]
Discovery of a Kuiper Belt Object in the Outer Solar System
HUBBLE DETECTION OF COMET NUCLEUS AT FRINGE OF SOLAR SYSTEM

This is sample data from NASA's Hubble Space Telescope that illustrates the detection of comets in the Kuiper Belt, a region of space beyond the orbit of the planet Neptune. This pair of images, taken with the Wide Field Planetary Camera 2 (WFPC2), shows one of the candidate Kuiper Belt objects found with Hubble. Believed to be an icy comet nucleus several miles across, the object is so distant and faint that Hubble's search is the equivalent of finding the proverbial needle-in-haystack.

Each photo is a 5-hour exposure of a piece of sky carefully selected such that it is nearly devoid of background stars and galaxies that could mask the elusive comet.

The left image, taken on August 22, 1994, shows the candidate comet object (inside circle) embedded in the background. The right picture, take of the same region one hour forty-five minutes later shows the object has apparently moved in the predicted direction and rate of motion for a kuiper belt member. The dotted line on the images is a possible orbit that this Kuiper belt comet is following. A star (lower right corner) and a galaxy (upper right corner) provide a static background reference. In addition, other objects in the picture have not moved during this time, indicating they are outside our solar system.

Through this search technique astronomers have identified 29 candidate comet nuclei belonging to an estimated population of 200 million particles orbiting the edge of our solar system. The Kupier Belt was theorized 40 years ago, and its larger members detected several years ago. However, Hubble has found the underlying population of normal comet-sized bodies.

Credit: A. Cochran (University of Texas) and NASA

Students for the Exploration and Development of Space

Created by R. Mark Elowitz
Maintained byGuy K. McArthur


庫伯帶網站請參考:http://www.ifa.hawaii.edu/faculty/jewitt/kb.html



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