| 词条 | 1SWASP J140747.93-394542.6 |
| 释义 |
|name=1SWASP J140747.93-394542.6 }}{{Starbox image |image= |caption= A graph of 1SWASP J1407 and J1407b to scale, showing the extent of the ring system }}{{Starbox observe |epoch = J2000 |constell = Centaurus |ra = 14 07 47.93[1] |dec = -39 45 42.7[1] |appmag_v = 12.31[1][1] }}{{Starbox character |class = K5 IV(e) Li[1] }}{{Starbox astrometry |prop_mo_ra = -25.4 ±1.4[1] |prop_mo_dec = -20.1 ±3.5[1] |dist_pc = 133 ±12[8] |dist_ly = 434 ±39[8] |parallax = 7.52 ±0.68[8] }}{{Starbox detail |mass = 0.9[1] |radius = 0.99 ±0.11[8] |temperature = 4400 ±100[8] |age = 16 million[1] }}{{Starbox reference |Simbad = 1SWASP+J140747.93-394542.6 |EPE = http://exoplanet.eu/catalog/1swasp_j1407_b/ }}{{Starbox end}} 1SWASP J140747.93-394542.6 (often abbreviated 1SWASP J140747 or J1407) is a star similar to the Sun in the constellation Centaurus at a distance of about 420 light years from Earth.[2] A relatively young star, its age is estimated to be 16 million years, and its mass is about 90% that of the Sun's.[3][4] The star has an apparent magnitude of 12.3 and requires a telescope to be seen.[1] The star's name comes from the SuperWASP (Wide Angle Search for Planets) program and the star's RA/Dec. J1407 is regularly{{Citation needed|reason=Has another eclipse been observed since 2007?|date=March 2019}} to a great extent eclipsed and orbited by at least one major body, 1SWASP J1407b[19] (J1407b), thought to be either a large gas giant planet or a brown dwarf with an immense ring system.[3][5][6] {{Anchor|J1407b}}1SWASP J140747.93-394542.6 bThe discovery of the J1407 system and its unusual eclipses were first reported by a team led by University of Rochester astronomer Eric Mamajek in 2012.[3] The existence and parameters of the ring system around the substellar companion J1407b were deduced from the observation of a very long and complex eclipse of the parent star lasting 56 days during April and May 2007.[3][4] The low-mass companion J1407b has been referred to as a "Saturn on steroids"[2][7] or “Super Saturn”[8] due to its massive system of circumplanetary rings with a radius of approximately 90 million km (0.6 AU).[5] The orbital period of J1407b is estimated to be around a decade (3.5 to 13.8 years), and its most probable mass is approximately 13 to 26 Jupiter masses, but with considerable uncertainty.[5] The ringed body can be ruled out as being a star with mass of over 80 Jupiter masses at greater than 99% confidence.[5] The ring system has an estimated mass similar to that of the Earth.[6] A major gap in the rings at about 61 million km (0.4 AU) from its centre is considered to be indirect evidence of the existence of an exomoon with mass up to 0.8 Earth masses.[5] J1407b is the first exoplanet or brown dwarf discovered with a ring system by the transit method. A sequence of occultations (eclipses) of the star occurred over a 56-day period in 2007. The pattern was consistent with that expected for the transit of a large array of multiple rings, indicating the substellar companion dubbed “J1407b”.[3] The J1407b ring system has an outer radius of approximately 90 million km (about 640 times the extent of Saturn’s rings).[9] Cleared gaps in the rings indicate satellites (“exomoons”) have formed accreted from denser rings. The young age of the stellar system (about 16 million years) and the high mass of the ring system (roughly an Earth mass) are more consistent with it being an early (proto-)exomoon or moons, rather than a long-term stable ring system in an evolved planetary system (such as Saturn's rings). From Earth's point of view, the ring system appears about 3.7 milliarcseconds across. For comparison, if Saturn were as many light years away, its rings in full breadth would be 0.006 milliarcseconds across.{{ref|1}} {{OrbitboxPlanet begin| table_ref = [10] }}{{OrbitboxPlanet | exoplanet = 1SWASP J1407b | mass = 20.0 ± 6.0 | semimajor = 3.9 ± 1.7 | period = 3725.0 ± 900.0 | eccentricity = }}{{Orbitbox end}} Notes1.{{note|1}} ring system diameter= 0.0000190 ly; distance = ~439 ly. 0.0000190/439=0.000000043 of the sky; 0.00000104 degrees; 0.000062 arminutes; 0.00374 arcseconds; 3.74 milliarcseconds See also
References1. ^1 {{cite simbad|title=1SWASP J140747.93-394542.6|access-date=2016-04-17}} 2. ^1 {{cite news |last=St. Fleur |first=Nicholas |title=Distant Ringed Object Could Be ‘Saturn on Steroids’ |url=https://www.nytimes.com/2016/10/14/science/exoplanet-rings-saturn-j1407b.html |date=October 13, 2016 |work=New York Times |accessdate=October 14, 2016 }} 3. ^1 2 3 4 5 6 7 8 9 10 11 12 {{Cite journal | first1=Eric E. | last1=Mamajek | first2=Alice C. | last2=Quillen | first3=Mark J. | last3=Pecaut | first4=Fred | last4=Moolekamp | first5=Erin L. | last5=Scott | first6=Matthew A. | last6=Kenworthy | first7=Andrew | last7=Collier Cameron | first8=Neil R. | last8=Parley | date=March 2012 | title=Planetary Construction Zones in Occultation: Discovery of an Extrasolar Ring System Transiting a Young Sun-like Star and Future Prospects for Detecting Eclipses by Circumsecondary and Circumplanetary Disks | journal=The Astronomical Journal | volume=143 |issue= | page=72 | arxiv=1108.4070 | bibcode=2012AJ....143...72M | doi=10.1088/0004-6256/143/3/72}} 4. ^1 {{cite web | url=http://www.ctio.noao.edu/noao/content/Eclipsing-Ring-System-J1407 | title=Eclipsing Ring System J1407 | publisher=Cerro Tololo Inter-American Observatory | date=June 22, 2012 | accessdate=January 27, 2015}} 5. ^1 2 3 4 5 6 7 8 9 {{Cite journal | first1=Matthew A. | last1=Kenworthy | first2=Eric E. | last2=Mamajek | title=Modeling giant extrasolar ring systems in eclipse and the case of J1407b: sculpting by exomoons? |arxiv=1501.05652 | date=January 22, 2015 | doi=10.1088/0004-637X/800/2/126 | volume=800 | journal=The Astrophysical Journal | page=126 | bibcode=2015ApJ...800..126K}} 6. ^1 {{cite news | url=http://www.eurekalert.org/pub_releases/2015-01/uor-grs012615.php | title=Gigantic ring system around J1407b much larger, heavier than Saturn's | publisher=University of Rochester | date=January 26, 2015 | accessdate=January 27, 2015}} 7. ^{{cite web | url=http://news.discovery.com/space/saturn-on-steroids-exoplanet-discovered-120111.htm | first=Ian | last=O'Neill | title='Saturn on Steroids' Exoplanet Discovered? | work=Discovery News | date=January 12, 2012 | accessdate=January 27, 2014}} 8. ^[https://www.rochester.edu/newscenter/gigantic-ring-system-around-j1407b/ Gigantic ring system around J1407b much larger, heavier than Saturn’s], on University of Rochester website. 9. ^{{cite web|last=Brumfield |first=Ben |url=http://www.cnn.com/2015/01/28/tech/giant-planetary-ring-system/index.html |title=Discovery: 'Super Saturn' with rings 200 times as big |publisher=CNN.com |date=2015-01-28 |accessdate=2017-06-01}} 10. ^1 {{cite web|url=http://exoplanet.eu/catalog/1swasp_j1407_b/ |title=The Extrasolar Planet Encyclopaedia — 1SWASP J1407 b |publisher=Exoplanet.eu |date=2014-10-29 |accessdate=2017-06-01}} External links
6 : Centaurus (constellation)|Planetary systems|Exoplanets|Planetary rings|Exoplanets discovered in 2012|K-type subgiants |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。