see § List of discovered minor planets |
David James Tholen (born 1955) is an American astronomer at the Institute for Astronomy of the University of Hawaii. He holds a 1984 PhD from the University of Arizona, and specializes in planetary and Solar System astronomy. He is a discoverer of minor planets and known for the Tholen spectral classification scheme used on asteroids. [2]
Tholen has discovered a number of asteroids, including the lost 1998 DK36 , which may be an Apohele asteroid, and 2004 XZ130, which certainly is; in fact, it had the smallest semimajor axis and aphelion distance among the known asteroids (and still holds both records among numbered asteroids as of March 2010 [3] ). He won the H. C. Urey Prize in 1990. [4]
He co-discovered the asteroid 99942 Apophis (previously known as 2004 MN4 ). This asteroid will closely approach Earth on April 13, 2029 and very briefly appear as bright as a third magnitude star.
In 1995, Tholen obtained images of the then newly discovered comet Hale-Bopp at a time when the comet was moving very slowly with respect to the background stars, thus permitting the red- green- and blue-filtered images to be combined into a color composite without the background stars appearing as separately colored dots. This color composite image was made publicly accessible via the Institute of Astronomy's web site.
Later, then postdoc at University of Hawaii, Olivier R. Hainaut discovered that a nearly identical image was being discussed by late-night radio host Art Bell and one of his guests, Courtney Brown, who claimed that it proved the existence of an unnatural object following the comet, something supposedly seen by those who had learned how to engage in the technique of "remote viewing". The image provided to Bell by Brown, and eventually made public on Bell's web site, did indeed show an object next to the comet that did not appear in archival images of the sky. In reality, that image had been digitally altered from the original image posted by Tholen, presumably by taking the image of a star near the edge of the frame, adding it next to the comet, and then trimming away the outer edges of the frame.
Tholen and Hainaut exposed the fraud by producing the original image, which showed no such additional object. Nevertheless, some conspiracy theorists maintained that Brown's version was actually the original image and that Tholen had removed the additional object from the one on the Institute's web site. The Heaven's Gate cult was so convinced that the additional object was a spaceship coming to take them away from Earth that they committed mass suicide.
The Mars-crosser asteroid 3255 Tholen, discovered by Edward Bowell in 1980, is named after David Tholen. [2]
David Tholen and Roy Tucker, co-discovers of 99942 Apophis, are both fans of the TV series Stargate SG-1, which influenced the naming of the asteroid. The show's most persistent villain is "Apophis", an alien also named for the Egyptian god. "We considered a number of names, but 'Apophis' kept floating to the top," says Tucker. "Apophis was a very fitting name for 2004 MN4 not only because of its threatening nature, but also because of its evolution from an Aten asteroid to an Apollo asteroid during the 2029 encounter.". [5]
Tholen is a fan of the University of Kansas Jayhawks college basketball team and the Kansas City Royals Major League Baseball team.
He also plays clarinet and bass clarinet for the Honolulu Community Concert Band and the Oahu Community Orchestra.
He is also a user of the OS/2, Linux, Windows, Solaris, and Mac OS operating systems.
Tholen frequently posts to various Usenet groups using the alias tholen@antispam.ham.
3124 Kansas | 3 November 1981 | list |
11606 Almary | 19 October 1995 | list |
17045 Markert | 22 March 1999 | list |
(24978) 1998 HJ151 | 28 April 1998 | list [A] [B] [C] |
(27002) 1998 DV9 | 23 February 1998 | list [D] |
49036 Pelion | 21 August 1998 | list [D] |
(72912) 2001 OA84 | 18 July 2001 | list |
(96744) 1999 OW3 | 18 July 1999 | list [D] |
(97725) 2000 GB147 | 2 April 2000 | list [D] |
99942 Apophis | 19 June 2004 | list [E] [F] |
(101818) 1999 JD13 | 14 May 1999 | list [D] |
(103501) 2000 AT245 | 8 January 2000 | list [D] |
(124198) 2001 OH77 | 18 July 2001 | list |
(137911) 2000 AB246 | 8 January 2000 | list [D] |
(139478) 2001 OP104 | 19 July 2001 | list |
(141498) 2002 EZ16 | 8 March 2002 | list |
(160848) 2001 BN82 | 19 January 2001 | list |
(164294) 2004 XZ130 | 13 December 2004 | list |
(164405) 2005 UK504 | 24 October 2005 | list |
(164406) 2005 UV504 | 24 October 2005 | list |
(168613) 2000 AA246 | 7 January 2000 | list [D] |
(168828) 2000 SY320 | 29 September 2000 | list |
(190208) 2006 AQ | 2 January 2006 | list |
(198968) 2005 UF506 | 24 October 2005 | list |
(198971) 2005 UU512 | 31 October 2005 | list |
(202420) 2005 UO506 | 24 October 2005 | list |
(209923) 2005 UX504 | 24 October 2005 | list |
(218017) 2001 XV266 | 9 December 2001 | list |
(229495) 2005 UG508 | 24 October 2005 | list |
(231134) 2005 TU45 | 5 October 2005 | list |
(231199) 2005 UO505 | 24 October 2005 | list |
(231200) 2005 UZ505 | 24 October 2005 | list |
(233166) 2005 UF508 | 24 October 2005 | list |
(238850) 2005 UL530 | 24 October 2005 | list |
(240790) 2005 UH505 | 24 October 2005 | list |
(248508) 2005 UY504 | 24 October 2005 | list |
(250706) 2005 RR6 | 4 September 2005 | list |
(265742) 2005 UG510 | 24 October 2005 | list |
(268427) 2005 UJ506 | 24 October 2005 | list |
(276891) 2004 RH340 | 15 September 2004 | list |
(277451) 2005 UT504 | 24 October 2005 | list |
(280491) 2004 MO7 | 16 June 2004 | list |
(280742) 2005 LY42 | 8 June 2005 | list |
(281070) 2006 OY10 | 21 July 2006 | list |
(284133) 2005 UP504 | 24 October 2005 | list |
(290759) 2005 UR505 | 24 October 2005 | list |
(303930) 2005 UZ503 | 24 October 2005 | list |
(306798) 2001 OW94 | 20 July 2001 | list |
(309203) 2007 GG | 7 April 2007 | list |
(326354) 2000 SJ344 | 30 September 2000 | list [D] |
(327398) 2005 UL505 | 24 October 2005 | list |
(357129) 2001 XU266 | 9 December 2001 | list |
(363071) 2000 GD147 | 3 April 2000 | list [D] |
(363831) 2005 PY16 | 1 August 2005 | list |
(383165) 2005 VJ5 | 7 November 2005 | list |
(396816) 2004 QU28 | 17 August 2004 | list |
(405762) 2005 YO180 | 29 December 2005 | list |
(437908) 2001 XW266 | 9 December 2001 | list |
(440680) 2005 YW36 | 23 December 2005 | list |
(455951) 2005 UQ504 | 24 October 2005 | list |
(474212) 2000 SH344 | 29 September 2000 | list [D] |
(480852) 2000 WK192 | 24 November 2000 | list |
(481027) 2004 XN44 | 13 December 2004 | list |
(503858) 1998 HQ151 | 28 April 1998 | list [A] [B] [C] |
541132 Leleākūhonua | 13 October 2015 | list [B] [G] |
(541152) 2017 EU9 | 24 April 2005 | list |
Co-discovery made with: A J. X. Luu B C. Trujillo C D. C. Jewitt D R. J. Whiteley E R. A. Tucker F F. Bernardi G S. S. Sheppard |
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An asteroid is a minor planet of the inner Solar System. Historically, these terms have been applied to any astronomical object orbiting the Sun that did not resolve into a disc in a telescope and was not observed to have characteristics of an active comet such as a tail. As minor planets in the outer Solar System were discovered that were found to have volatile-rich surfaces similar to comets, these came to be distinguished from the objects found in the main asteroid belt. Thus the term "asteroid" now generally refers to the minor planets of the inner Solar System, including those co-orbital with Jupiter. Larger asteroids are often called planetoids.
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Brett James Gladman is a Canadian astronomer and a full professor at the University of British Columbia's Department of Physics and Astronomy in Vancouver, British Columbia. He holds the Canada Research Chair in planetary astronomy. He does both theoretical work and observational optical astronomy.
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(433953) 1997 XR2 is a sub-kilometer sized asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group. It was discovered on 4 December 1997, by the Lincoln Near-Earth Asteroid Research (LINEAR) program at Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico, in the United States.
Eleanor Francis "Glo" Helin was an American astronomer. She was principal investigator of the Near-Earth Asteroid Tracking (NEAT) program of NASA's Jet Propulsion Laboratory.
Roy A. Tucker (born 1951 in Jackson, Mississippi) is an American astronomer best known for the co-discovery of near-Earth asteroid 99942 Apophis (formerly known as 2004 MN4) along with David J. Tholen and Fabrizio Bernardi of the University of Hawaii. He is a prolific discoverer of minor planets, credited by the Minor Planet Center with the discovery of 702 numbered minor planets between 1996 and 2010. He has also discovered two comets: 328P/LONEOS–Tucker and C/2004 Q1, a Jupiter-family and near-parabolic comet, respectively.
The Palomar Planet-Crossing Asteroid Survey (PCAS) was an astronomical survey, initiated by American astronomers Eleanor Helin and Eugene Shoemaker at the U.S Palomar Observatory, California, in 1973. The program is responsible for the discovery of 95 near-Earth Objects including 17 comets, while the Minor Planet Center directly credits PCAS with the discovery of 20 numbered minor planets during 1993–1994. PCAS ran for nearly 25 years until June 1995. It had an international extension, INAS, and was the immediate predecessor of the outstandingly successful NEAT program.
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2101 Adonis, provisional designation: 1936 CA, is an asteroid on an extremely eccentric orbit, classified as potentially hazardous asteroid and near-Earth object of the Apollo group. Adonis measures approximately 1 kilometer in diameter. Discovered by Eugène Delporte at Uccle in 1936, it became a lost asteroid until 1977. It may also be an extinct comet and a source of meteor showers. It was named after Adonis from Greek mythology.
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3255 Tholen, provisional designation 1980 RA, is a stony asteroid, Mars-crosser and relatively fast rotator, that measures approximately 5.1 kilometers in diameter. It was discovered on 2 September 1980, by American astronomer Edward Bowell at Lowell's Anderson Mesa Station in Flagstaff, Arizona. The S-type asteroid has a rotation period of 2.95 hours. It was later named after American astronomer David Tholen.
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