Nemesis (hypothetical star)
- Afrikaans
- العربية
- Беларуская
- Bosanski
- Català
- Čeština
- Dansk
- Deutsch
- Ελληνικά
- Emiliàn e rumagnòl
- Español
- Esperanto
- Euskara
- فارسی
- Français
- Gaeilge
- Galego
- 한국어
- Հայերեն
- Hrvatski
- Bahasa Indonesia
- Italiano
- עברית
- Lietuvių
- Magyar
- Македонски
- Bahasa Melayu
- Nederlands
- 日本語
- Norsk bokmål
- Polski
- Português
- Română
- Русский
- Slovenčina
- Српски / srpski
- Suomi
- Svenska
- தமிழ்
- Українська
- Tiếng Việt
- 中文
More recent theories suggest that other forces, like close
Using newer and more powerful infrared telescope technology which is able to detect brown dwarfs as cool as 150 kelvins out to a distance of 10 light-years from the Sun,[12] the Wide-field Infrared Survey Explorer (WISE survey) has not detected Nemesis.[13][14] In 2011, David Morrison, a senior scientist at NASA known for his work in risk assessment of near Earth objects, has written that there is no confidence in the existence of an object like Nemesis, since it should have been detected in infrared sky surveys.[13][15][16][17]
Claimed periodicity of mass extinctions
In 1984,
In 2010, Melott & Bambach re-examined the fossil data, including the now-improved dating, and using a second independent database in addition to that Raup & Sepkoski had used. They found evidence for a signal showing an excess extinction rate with a 27-million-year periodicity, now going back 500 million years, and at a much higher statistical significance than in the older work.[9]
Development of the Nemesis hypotheses
Two teams of
If it does exist, the exact nature of Nemesis is uncertain. Muller suggests that the most likely object is a
As of 2012[update], more than 1800 brown dwarfs have been identified.
Muller, referring to the date of a recent extinction at 11 million years before the present day, posits that Nemesis has a
In 2010, and again in 2013, Melott & Bambach found evidence for a signal showing an excess extinction rate with a 27-million-year periodicity. However, because Nemesis is so distant from the Sun, it is expected to be subject to perturbations by passing stars, and therefore its orbital period should shift by 15–30%. The existence of a sharp 27-million year peak in extinction events is therefore inconsistent with Nemesis.[9][26]
Orbit of Sedna
The trans-Neptunian object Sedna has an extra-long and unusual elliptical orbit around the Sun,[2] ranging between 76 and 937 AU. Sedna's orbit takes about 11,400 years to complete once. Its discoverer, Michael Brown of Caltech, noted in a Discover magazine article that Sedna's location seemed to defy reasoning: "Sedna shouldn't be there", Brown said. "There's no way to put Sedna where it is. It never comes close enough to be affected by the Sun, but it never goes far enough away from the Sun to be affected by other stars."[27] Brown therefore postulated that a massive unseen object may be responsible for Sedna's anomalous orbit.[2] This line of inquiry eventually led to the hypothesis of Planet Nine.
Brown has stated that it is more likely that one or more non-companion stars, passing near the Sun billions of years ago, could have pulled Sedna out into its current orbit.[27] In 2004, Kenyon forwarded this explanation after analysis of Sedna's orbital data and computer modeling of possible ancient non-companion star passes.[8]
Past, current, and pending searches for Nemesis
Searches for Nemesis in the infrared are important because cooler stars comparatively shine brighter in infrared light. The
In particular, if Nemesis is a
Calculations in the 1980s suggested that a Nemesis object would have an irregular orbit due to perturbations from the galaxy and passing stars. The Melott and Bambach work[9] shows an extremely regular signal, inconsistent with the expected irregularities in such an orbit. Thus, while supporting the extinction periodicity, it appears to be inconsistent with the Nemesis hypothesis, though of course not inconsistent with other kinds of substellar objects. According to a 2011 NASA news release, "recent scientific analysis no longer supports the idea that extinctions on Earth happen at regular, repeating intervals, and thus, the Nemesis hypothesis is no longer needed."[32]
See also
- Counter-Earth
- Giant-impact hypothesis
- Lists of astronomical objects
- Nemesis (Asimov novel)
- Malmquist bias
- Planet Nine
- Planets beyond Neptune
- Shiva hypothesis
- Theia (planet)
- Tyche (hypothetical planet)
- Vulcan (hypothetical planet)
References
- ^ Leader-Post, "Scientists claim killer star exists", 22 Feb 1984, Page B6, Associated Press
- ^ a b c d e f g Leslie Mullen (11 March 2010). "Getting WISE About Nemesis". Astrobiology Magazine (Cosmic Evolution). Archived from the original on 14 March 2010. Retrieved 2010-05-15.
{{cite web}}
: CS1 maint: unfit URL (link) - ^ M. Davis, P. Hut, and R. Muller, “Extinction of species by periodic comet showers”, Nature 308, 715 (1984).
- ^ PMID 6583680. Retrieved 30 April 2007.
- ^ "New evidence that all stars are born in pairs". Berkeley News. 2017-06-13. Retrieved 2018-06-19.
- S2CID 119341787.
- ^ Levine, David (2018-06-19). "All stars in the universe may form in pairs — but we can't find the sun's missing 'Nemesis'". Business Insider. Retrieved 2018-06-19.
- ^ a b
Kenyon, Scott J.; Benjamin C. Bromley (2004). "Stellar encounters as the origin of distant Solar System objects in highly eccentric orbits". Nature. 432 (7017): 598–602. S2CID 4427211.
- ^ S2CID 7911150.
- ^ "Nemesis is a myth". Max Planck. August 1, 2011. Retrieved 2011-10-07.
- ^ Leslie Mullen (Astrobiology Magazine) (11 March 2010). "Sun's Nemesis Pelted Earth with Comets, Study Suggests". Space.com. Retrieved 2010-08-22.
- ^ a b "Science: Brown Dwarfs". WISE/NASA. Retrieved 2007-12-28.
- ^ a b David Morrison (October 17, 2012). "The idea has been disproved by several infrared sky surveys, most recently the WISE mission". NASA Ask An Astrobiologist. Archived from the original on October 23, 2012. Retrieved 2012-10-18.
- S2CID 16850733.
- ^ David Morrison (August 2, 2011). "Scientists today no longer think an object like Nemesis could exist". NASA Ask An Astrobiologist. Archived from the original on December 13, 2012. Retrieved 2011-10-22.
- ^ David Morrison (November 25, 2010). "this hypothetical Nemesis does not exist". NASA Ask An Astrobiologist. Archived from the original on December 13, 2012. Retrieved 2011-11-09.
- ^ "NASA's WISE Survey Finds Thousands of New Stars, But No 'Planet X'". Nasa JPL. 2014-03-07. Retrieved 2014-03-15.
- ^ S2CID 4236610.
- ^ S2CID 4267612.
- ^ a b c Richard A. Muller. "Nemesis". Lawrence Berkeley National Laboratory. Retrieved 2007-05-19.
- doi:10.1086/104156.
- ^ a b Richard A. Muller (2002). "Measurement of the lunar impact record for the past 3.5 billion years, and implications for the Nemesis theory" (PDF). Geol. Soc. of America Special Paper 356, pp 659–665 (2002). Retrieved 2011-11-11.
- ^ Chris Gelino, Davy Kirkpatrick, Adam Burgasser (6 November 2012). "DwarfArchives.org: Photometry, spectroscopy, and astrometry of M, L, and T dwarfs". caltech.edu. Retrieved 2012-12-28.
{{cite web}}
: CS1 maint: multiple names: authors list (link) (M=536, L=918, T=355, Y=14) - ^ Ian O'Neill (Discovery News) (12 June 2012). "Brown Dwarfs, Runts of Stellar Litter, Rarer than Thought". Space.com. Retrieved 2012-12-28.
- S2CID 368553.
- S2CID 15985292.
- ^ a b Cal Fussman (May 27, 2006). "The Man Who Finds Planets". Discover magazine. Retrieved 2011-10-20.
- ^ Perlmutter, Saul (1986). An Astrometric Search for a Stellar Companion to the Sun (Ph.D. thesis). University of California, Berkeley.
- ^ "NASA – WISE Delivers Millions of Galaxies, Stars, Asteroids". Nasa.gov. Retrieved 2011-06-15.
- ^ "NASA Releases New WISE Mission Catalog of Entire Infrared Sky". Nasa JPL. 2012-03-14. Retrieved 2012-03-15.
- ^ NASA's WISE Survey Finds Thousands of New Stars, But No 'Planet X'
- ^ "Can WISE Find the Hypothetical 'Tyche'?". NASA/JPL. February 18, 2011. Retrieved 2022-03-28.
External links
- "Astrobiology Magazine", "Cosmic Evolution" Section, "Getting WISE about Nemesis" 03/11/10, Author: Leslie Mullen, Article about Nemesis and Tyche theory, and how the WISE Sky Survey Mission may prove or disprove the theories.
- Robert Roy Britt, Nemesis: Does the Sun Have a 'Companion'?, Space.com, 3 April 2001.
- Foot R., Silagadze Z. K. (2001). "Do mirror planets exist in our solar system?". Acta Physica Polonica. B32 (7): 2271–2278. Bibcode:2001AcPPB..32.2271F.
- Richard A. Muller, Measurement of the lunar impact record for the past 3.5 billion years, and implications for the Nemesis theory, Geological Society of America Special Paper 356, pp 659–665 (2002). I
- Richard A. Muller, Nemesis (Weidenfeld & Nicolson, 1988, OP)
- Richard A. Muller, lecture where he describes Nemesis Theory
- Z.K. Silagadze, TeV scale gravity, mirror universe, and ... dinosaurs, Acta Physica Polonica B32 (2001) 99–128. (Provides a very entertaining and readable review of the Nemesis extinction hypothesis, including dozens of references to scientific articles on the topic.)
- SpaceDaily. Evidence Mounts For Companion Star To Our Sun. Apr 25, 2006
- Lynn Yarris. "Does a Companion Star to the Sun Cause Earth's Periodic Mass Extinctions?" Science Beat. Spring 1987
- Nemesis is a myth (Max Planck August 1, 2011)
Technological | |||||
---|---|---|---|---|---|
Sociological | |||||
Ecological |
| ||||
Biological |
| ||||
Astronomical | |||||
Eschatological | |||||
Others |
| ||||
Fictional | |||||
Organizations | |||||
General | |||||