Editing Kuiper belt (section)

== Extrasolar Kuiper belts ==
{{Main|Debris disc}}
[[File:Kuiper belt remote.jpg|thumb|upright=1.25|Debris discs around the stars [[HD 139664]] and [[HD 53143]] – black circle from [[coronograph|camera]] hiding stars to display discs.]]

By 2006, astronomers had resolved dust discs thought to be Kuiper belt-like structures around nine stars other than the Sun. They appear to fall into two categories: wide belts, with radii of over 50 AU, and narrow belts (tentatively like that of the Solar System) with radii of between 20 and 30 AU and relatively sharp boundaries.<ref name="Kalas et al. 2006"/> Beyond this, 15–20% of solar-type stars have an observed [[infrared excess]] that is suggestive of massive Kuiper-belt-like structures.<ref>{{cite journal |title=Debris Disks around Sun-like Stars |author=Trilling, D. E. |author2=Bryden, G. |author3=Beichman, C. A. |author4=Rieke, G. H. |author5=Su, K. Y. L. |author6=Stansberry, J. A. |author7=Blaylock, M. |author8=Stapelfeldt, K. R. |author9=Beeman, J. W. |author10=Haller, E. E. |volume=674 |issue=2 |pages=1086–1105 |date=February 2008 |bibcode=2008ApJ...674.1086T |doi=10.1086/525514 |journal=The Astrophysical Journal |arxiv=0710.5498|s2cid=54940779 }}</ref> Most known [[debris disc]]s around other stars are fairly young, but the two images on the right, taken by the Hubble Space Telescope in January 2006, are old enough (roughly 300 million years) to have settled into stable configurations. The left image is a "top view" of a wide belt, and the right image is an "edge view" of a narrow belt.<ref name="Kalas et al. 2006">{{cite journal |bibcode=2006ApJ...637L..57K |arxiv=astro-ph/0601488 |title=First Scattered Light Images of Debris Disks around HD 53143 and HD 139664 |last1=Kalas |first1=Paul |last2=Graham |first2=James R. |last3=Clampin |first3=Mark C. |last4=Fitzgerald |first4=Michael P. |volume=637 |issue=1 |date=2006 |pages=L57 |journal=The Astrophysical Journal |doi=10.1086/500305|s2cid=18293244 }}</ref><ref>{{cite web |title=Dusty Planetary Disks Around Two Nearby Stars Resemble Our Kuiper Belt |url=http://hubblesite.org/newscenter/archive/releases/2006/05/image/a |date=2006 |access-date=1 July 2007 |archive-date=9 July 2016 |archive-url=https://web.archive.org/web/20160709094354/http://hubblesite.org/newscenter/archive/releases/2006/05/image/a/ |url-status=live }}</ref> Computer simulations of dust in the Kuiper belt suggest that when it was younger, it may have resembled the narrow rings seen around younger stars.<ref>{{cite journal |title=Collisional Grooming Models of the Kuiper Belt Dust Cloud |author=Kuchner, M. J. |author2=Stark, C. C. |volume=140 |issue=4 |pages=1007–1019 |date=2010 |bibcode=2010AJ....140.1007K |doi=10.1088/0004-6256/140/4/1007 |journal=The Astronomical Journal |arxiv=1008.0904|s2cid=119208483 }}</ref>