Tyche is the nickname given to a possible gas giant planet in the Solar System's Oort cloud. It is one of several proposed planets beyond Neptune. Tyche was first proposed in 1999 by astronomer John Matese of the University of Louisiana at Lafayette.
Matese and Daniel Whitmire say that the points of origin for long-period comets gives a pattern that suggests Tyche's existence. They noted that Tyche, if it exists, should be seen in the archive of data that was collected by NASA's Wide-field Infrared Survey Explorer (WISE) Infrared telescope. However, several astronomers disagree that Tyche exists. In 2014 NASA announced that WISE had not found such a planet. 
References[change | change source]
- Rodgers, Paul (13 February 2011). "Up telescope! Search begins for giant new planet". The Independent. https://www.independent.co.uk/news/science/up-telescope-search-begins-for-giant-new-planet-2213119.html. Retrieved February 14, 2011.
- Wolchover, Natalie (2011). "Article: Astronomers doubt giant planet 'Tyche' exists in our Solar System". Space.com. http://www.space.com/10863-mystery-planet-tyche-debate.html. Retrieved February 15, 2011.
- Matese, John J.; Whitmire, Daniel P. (2011). "Persistent evidence of a jovian mass solar companion in the Oort cloud" (PDF). Icarus 211 (2): 926–938. doi:10.1016/j.icarus.2010.11.009. http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.4584v1.pdf.
- Plait, Phil (2011). "No, there’s no proof of a giant planet in the outer Solar System". Discovery Magazine. http://blogs.discovermagazine.com/badastronomy/2011/02/14/no-theres-no-proof-of-a-giant-planet-in-the-outer-solar-system/#more-28256. Retrieved February 15, 2011.
- Helhoski, Anna. "News 02/16/11 Does the Solar System have giant new planet?". The Norwalk Daily Voice. http://norwalk.dailyvoice.com/news/does-solar-system-have-giant-new-planet. Retrieved 10 July 2012.