David James Tholen (born 1955) is an American astronomer at the Institute for Astronomy of the University of Hawaiʻi. He holds a 1978 B.S. from the University of Kansas,[3] 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.[4]
David Tholen | |
|---|---|
| Education | University of Kansas (BS) University of Arizona (PhD) |
| Known for | Search for minor planets |
| Awards | Harold C. Urey Prize (1990) |
| Scientific career | |
| Fields | Astronomy Planetary science |
| Thesis | Asteroid Taxonomy from Cluster Analysis of Photometry. (1984) |
| Doctoral advisor | Benjamin Zellner[1] |
| Website | legacy |
| see § List of discovered minor planets |
Professional life
editTholen 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[5]). He won the H. C. Urey Prize in 1990.[6]
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 Hawaiʻi, 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.[4]
Personal interests
editDavid 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."[7]
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.
List of discovered minor planets
edit| 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 | ||
|---|---|---|
See also
editReferences
edit- ^ Tholen, David (1984). Asteroid Taxonomy from Cluster Analysis of Photometry (PhD thesis). The University of Arizona. Retrieved December 16, 2024.
- ^ "Minor Planet Discoverers (by number)". Minor Planet Center. January 12, 2017. Retrieved February 1, 2017.
- ^ "David James Tholen". prabook.com. Retrieved December 16, 2024.
- ^ a b Schmadel, Lutz D. (2007). "(3255) Tholen". Dictionary of Minor Planet Names – (3255) Tholen. Springer Berlin Heidelberg. p. 271. doi:10.1007/978-3-540-29925-7_3256. ISBN 978-3-540-00238-3.
- ^ "List Of Aten Minor Planets". Minor Planet Center. February 4, 2010. Retrieved January 8, 2011.
- ^ "Harold C. Urey Prize in Planetary Science".
- ^ Bill Cooke (August 18, 2005). "Asteroid Apophis set for a makeover". Astronomy Magazine. Archived from the original on November 10, 2005. (naming the asteroid Apophis and how Earth's gravity may change its trajectory in 2029)