Jump to content

TRAPPIST-1

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Quantanew (talk | contribs) at 21:47, 6 May 2016 (diameter). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

TRAPPIST 1[1]

This chart shows the naked eye stars visible on a clear dark night in the sprawling constellation of Aquarius (The Water Carrier). The position of the faint and very red ultracool dwarf star TRAPPIST-1 is marked. Although it is relatively close to the Sun it is very faint and not visible in small telescopes.
Credit: ESO/IAU and Sky & Telescope
Observation data
Epoch       Equinox
Constellation Aquarius
Right ascension 23h 06m 29.283s[2]
Declination –05° 02′ 28.59″[2]
Apparent magnitude (V) 18.80
Characteristics
Spectral type M8[3]: 1236 
V−R color index 2.33
R−I color index 2.47
Astrometry
Radial velocity (Rv)-56.3 km/s
Parallax (π)82.58 mas
Distance39.5±1.3 ly
(12.1±0.4 pc)
Absolute magnitude (MV)18.4 ±0.1
Details
Mass0.08±0.009 M☉
Mass83.8048±9.428 MJup
Radius0.114±0.006 R☉
Luminosity (bolometric)0.000525±0.000036[4] L☉
Luminosity (visual, LV)0.00000373[note 1] L☉
Surface gravity (log g)~5.227[note 2][5] cgs
Temperature2550±55 K
Metallicity0.04±0.08
Rotation1.40 ± 0.05 days
Rotational velocity (v sin i)6 ± 2 km/s
Age> 0.5000 Gyr
Other designations
2MASS J23062928-0502285, 2MASSI J2306292-050227, 2MASSW J2306292-050227, 2MUDC 12171
Database references
SIMBADdata
Planets
TRAPPIST-1b
TRAPPIST-1c
TRAPPIST-1d
Data sources:

2MASS J23062928-0502285,[6] also known as TRAPPIST-1, is an ultracool dwarf star.[4][7] located 39.13 light-years (12.0 pc) away in the Aquarius constellation.

A team of astronomers headed by Michaël Gillon of the Institut d’Astrophysique et Géophysique at the University of Liège[8] in Belgium used the TRAPPIST (Transiting Planets and Planetesimals Small Telescope) telescope at the La Silla Observatory in the Atacama desert, Chile,[9] to observe TRAPPIST-1 and search for orbiting planets. By utilising transit photometry, they discovered three Earth-sized planets orbiting the dwarf star; the innermost two are tidally locked to their host star while the outermost appears to lie either within the system's habitable zone or just outside of it.[7][10] The team made their observations from September to December 2015 and published its findings in the May 2016 issue of the journal Nature.[9][11]

The ultracool dwarf star is not much larger in diameter than Jupiter and emits a tiny fraction of our Sun's total luminosity.[9] The three small planets orbit the dwarf closely (at 1%, 1.5% and 3% of the distance that the Earth orbits from the Sun). A year on the closest planet passes in only 1.5 Earth days, the second is in 2.4 Earth days and the orbit of the third planet is less certain, with a year passing in 4.5 to 73 Earth days.[9] It is important to note that tidally locked planets likely have very large differences in temperature between their permanently lit daysides and their permanently dark nightsides, which could produce very strong winds circling the planets while making the best places for life close to the mild twilight regions between the 2 sides.

Planetary system

Planet
 Mass
(M⊕) 		Radius
(R⊕) 		Period
(Days) 		Semimajor
orbit (Day) 		Eccentricity Insolation
(I⊕)
b − 1.113 ± 0.044 1.510848 ± 0.000019 0.01111 0 4.25 ± 0.38
c − 1.049 ± 0.050 2.421848 ± 0.000028 0.01522 0 2.26 ± 0.21
d − 1.163 ± 0.065 4.551–72.820 – 0 0.02–1

Template:TRAPPIST-1 Gallery

Notes

  1. ^ Taking the absolute visual magnitude of TRAPPIST-1 and the absolute visual magnitude of the Sun , the visual luminosity can be calculated by
  2. ^ The surface gravity is calculated directly from Newton's law of universal gravitation, which gives the formula where M is the mass of the object, r is its radius, and G is the gravitational constant.

References

  1. ^ "TRAPPIST-1b". Open Exoplanet Catalogue. Retrieved 2016-05-02.
  2. ^ a b Cutri, R.M.; Skrutskie, M.F.; Van Dyk, S.; Beichman, C.A.; Carpenter, J.M.; Chester, T.; Cambresy, L.; Evans, T.; Fowler, J.; Gizis, J.; Howard, E.; Huchra, J.; Jarrett, T.; Kopan, E.L.; Kirkpatrick, J.D.; Light, R.M.; Marsh, K.A.; McCallon, H.; Schneider, S.; Stiening, R.; Sykes, M.; Weinberg, M.; Wheaton, W.A.; Wheelock, S.; Zacarias, N. (June 2003). "2MASS All Sky Catalog of point sources". VizieR Online Data Catalog. 2246. European Southern Observatory with data provided by the SAO/NASA Astrophysics Data System. Bibcode:2003yCat.2246....0C.
  3. ^ Costa, E.; Mendez, R.A.; Jao, W.-C.; Henry, T.J.; Subasavage, J.P.; Ianna, P.A. (August 4, 2006). "The Solar Neighborhood. XVI. Parallaxes from CTIOPI: Final Results from the 1.5 m Telescope Program" (PDF). The Astronomical Journal. 132 (3). The American Astronomical Society. Bibcode:2006AJ....132.1234C. doi:10.1086/505706.
  4. ^ a b Temperate Earth-sized planets transiting a nearby ultracool dwarf star. eso.org. (pdf)
  5. ^ Viti, Serena; Jones,, Hugh R. A. (November 1999). "Gravity dependence at the bottom of the main sequence". Astronomy and Astrophysics. 351: 1028–1035. Bibcode:1999A&A...351.1028V. Retrieved 6 May 2016.{{cite journal}}: CS1 maint: extra punctuation (link)
  6. ^ 2MASS J23062928-0502285
  7. ^ a b "Three Potentially Habitable Worlds Found Around Nearby Ultracool Dwarf Star - Currently the best place to search for life beyond the Solar System". eso.org. Retrieved 2016-05-02.
  8. ^ Institut d’Astrophysique et Géophysique at the University of Liège
  9. ^ a b c d "Could these newly-discovered planets orbiting an ultracool dwarf host life?". The Guardian. 2 May 2016.
  10. ^ "Three New Planets Are the Best Bets for Life". Popular Mechanics. 2016-05-02. Retrieved 2016-05-02.
  11. ^ http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17448.html

Further reading

Retrieved from "https://en.wikipedia.org/w/index.php?title=TRAPPIST-1&oldid=718990448"