Kepler-18 c (GSC 03149-02089 c, KIC 8644288 c, 2MASS J19521906 + 4444467 c [2] ) is the second of three exoplanets in the star Kepler-18 in the constellation Cygnus. [1] [3]
| Kepler-18 c | |
|---|---|
| Exoplanet | |
| Parent star | |
| Star | Kepler-18 (KOI-137) |
| Constellation | Swan |
| Right Ascension ( α ) | 19 h 52 m 19.067 s |
| Declination ( δ ) | + 44 ° 44 ′ 46.94 ″ |
| Visible magnitude ( m V ) | 13.549 |
| Distance | 1761 St. year ( 540 pc ) |
| Spectral class | Gv |
| Weight ( m ) | 0.972 ± 0.042 M ☉ |
| Radius ( r ) | 1.108 ± 0.051 R ☉ |
| Temperature ( T ) | 5383 ± 44 K |
| Metallicity ([Fe / H]) | + 0.200 ± 0.04 |
| Age | 10.0 ± 2.3 Ga |
| Elements of the orbit | |
| Semimajor axis ( a ) | 0.0752 ± 0.00125 a. e. |
| Eccentricity ( e ) | 0 |
| Orbital Period ( P ) | 7.64159 ± 3 × 10 -5 d. |
| Inclination ( i ) | 87.68 ± 0.22 ° |
| Pericenter Argument ( ω ) | 31 ± 16.9 ° |
| Pericenter Time ( T 0 ) | 2455165.83 ± 0.36 JD |
| physical characteristics | |
| Weight ( m ) | 17.3 ± 1.9 M ⊕ |
| Minimum Weight ( m sin i ) | 0.0544 ± 0.006 M J |
| Radius ( r ) | 0.49 ± 0.023 R J ( 5.49 ± 0.26 R ⊕ ) |
| Density ( ρ ) | 0.59 ± 0.07 g / cm 3 |
| Gravity ( g ) | 3.1 g |
| Temperature ( T ) | 911.1 K |
| Discovery Information | |
| opening date | December 20, 2011 |
| Detection method | Transit |
| Opening place | Kepler telescope |
| Opening status | Published [1] |
| Other designations | |
| GSC 03149-02089 s, KIC 8644288 s, 2MASS J19521906 + 4444467 s [2] | |
The exoplanet belongs to the class of hot Neptunes and is a gas giant heated to 911 Kelvin, which does not have a solid surface. Its average density is much lower than that of Neptune , which indicates a small number of heavy elements in the chemical composition. The radius of Kepler-18 with is equal to five earth radii. It is drawn at a distance of 0.075 a. e. from the star, making a complete revolution in seven and a half days.
The authors of the discovery calculated that the planet has a massive core and there is a 2: 1 orbital resonance with the planet Kepler-18 d .
Content
- 1 Native Star
- 2 See also
- 3 notes
- 4 Literature
- 5 Articles
- 6 References
- 7 Catalogs
Native Star
The star Kepler-20, also known as GSC 03149-02089, belongs to the stars of the spectral class GV. The star is located 1761 light-years from Earth in the constellation Cygnus. At least three planets revolve around a star [1] [3]
Kepler-18 - a star of 13.5 magnitude, in its parameters similar to our Sun. Its mass and radius are almost identical to the sun; surface temperature is about 5345 kelvin . The chemical composition of the star revealed an increased content of heavy elements. However, Kepler-18 is much older than our Sun in age - it is about 10 billion years old. The star got its name in honor of the Kepler space telescope, which discovered its planets. [1] [3]
See also
- Kepler-18
- List of exoplanets discovered in 2011
- List of exoplanets discovered by the Kepler telescope
- Kepler (telescope)
Notes
- ↑ 1 2 3 4 1110.0820v1, 2011 .
- ↑ 1 2 NASA Exoplanet Archive .
- ↑ 1 2 3 1102.0541v2, 2011 .
Literature
- Michael Perryman Part 6. Transits // The Exoplanet Handbook . - Cambridge University Press , 2011 .-- pp. 103-114. - 424 p. - ISBN 9780521765596 . Archived July 21, 2013 to Wayback Machine
Articles
- William D. Cochran et all. Kepler 18-b, c, and d: A System Of Three Planets Confirmed by Transit Timing Variations, Lightcurve Validation, Spitzer Photometry and Radial Velocity Measurements . - 2011. - arXiv : 1110.0820v1 .
- William J. Borucki. Characteristics of planetary candidates observed by Kepler, II: Analysis of the first four months of data . - 2011 .-- arXiv : 1102.0541v2 .
- Stephen R. Kane, Dawn M. Gelino. Decoupling Phase Variations in Multi-Planet Systems (Eng.) // The Astrophysical Journal . - 2012. - arXiv : 1211.6747v1 .
Links
- NASA's Kepler announces 11 planetary systems hosting 26 planets Ames Research Center. Archived July 10, 2013.
Directories
- Kepler-18 c . exoplanets.org. Archived July 11, 2013.
- Kepler-18 from (English) (inaccessible link) . Open Exoplanet Catalog. Archived July 11, 2013.
- Kepler-18 from (English) (inaccessible link - history ) . Ames Research Center.
- Kepler-18 c . NASA Exoplanet Archive. Archived July 11, 2013.
- Kepler-18 c . SIMBAD Archived July 11, 2013.