|
Exoplanet Name : |
KELT-21 b |
|
Alternate Name : |
|
|
Status : |
Confirmed |
|
Radius (Rjup / Re): |
1.5860 |
(Rjup) |
17.7775 |
(Rearth) |
|
Mass (Mjup / Me): |
3.9100 |
(Mjup) |
1243.1376 |
(Mearth) |
|
Semi Major Axis / Orbital Distance Calculated |
0.0522 |
(AU) |
0.0522 |
(AU Est.) |
|
Eccentricity : |
0.0000 |
|
Orbital Period(Yrs) |
0.0099 |
|
Orbital Period(Observed/Estimated) |
3.61 |
(Days Obs.) |
3.61 |
(Days Est.) |
|
Surface Gravity (G Earth) |
3.9335 |
|
Star Radiation at Atmospheric Boundary: |
4018124.8 |
(W/m2) |
|
Measured Temperature (K) |
0.0 |
(K) |
|
Blackbody T 0.1(K) |
1998.2 |
(K) |
|
Blackbody T 0.3(K) |
1876.6 |
(K) |
|
Blackbody T 0.7(K) |
1518.3 |
(K) |
|
Tidally Locked Blackbody T 0.1(K) |
2376.3 |
(K) |
|
Tidally Locked Blackbody T 0.3(K) |
2231.6 |
(K) |
|
Size Class: |
Super-Jupiter-size |
|
Mass Class: |
|
|
Detection Type : |
Primary Transit |
|
Mass Detection : |
Radial Velocity |
|
Radius Detection : |
Primary Transit |
|
Habitability by Solar Eq. Astronomical Unit: |
Not habitable |
|
Habitability by Kopparapu: |
Not habitable |
|
Star Name : |
KELT-21 |
|
Alternate Name : |
|
|
Star Distance(LY) : |
1353.5 |
|
Stellar Radius(Rsun) : |
1.6 |
(Rsun Measured) |
|
Stellar Mass(Msun) : |
1.5 |
(Msun Measured) |
1.5 |
(Msun Estimated) |
|
Star Age : |
1.6 |
(GY) |
|
Temperature : |
7598 |
(K) |
|
Spectral type : |
A8V |
|
UV portion[%]: |
0.3 |
|
Visible portion[%]: |
1.5 |
|
IR portion[%]: |
98.2 |
|
Metalicity : |
-0.4 |
|
Absolute Magnitude: |
2.4 |
|
Apparent Magnitude: |
10.5 |
|
Right Ascension(RA) |
304.8000 |
|
Declination (DEC) |
32.5811 |
|
Hubble Space Telescope Guide Star Catalog (GSC) ID |
|
|
Discovered by |
|
|
Discovery Paper - Authors |
|
|
Discovery Paper - Title |
|
|
Discovery Paper - Journal |
|
|
Discovery Paper - URL |
|
|
SIMBAD LINK |
https://simbad.u-strasbg.fr/simbad/sim-basic?Ident=KELT-21&submit=SIMBAD+search |
|
Open Exoplanet Database Link |
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KELT-21 b
KELT-21 b
KELT-21 b is an exoplanet orbiting the star KELT-21, located about 1353.5 light-years (415.0 pc) away from Solar System. Its discovery was publicly announced on 2017.
The host star KELT-21 has apparent magnitude of 10.5, with absolute magnitude of 2.4. It is 1.5 times more massive and 1.6 times bigger compared with our Sun. The surface temperature is 7598 with its spectral types of A8V
In this planetary system, the extrasolar planet KELT-21 b orbits around the star KELT-21 every 3.6 days with its orbital distance of 0.05 AU ( 7814992.8 km)
(Projected orbit of KELT-21 b around its host star KELT-21)
The Star KELT-21 's habitable zone is located at the following distance
Inner Boundary (the orbital distance at Venus's Equivalent Radiation )
: 2.049 AU ( 306457735.6 km)
Earth Boundary (the orbital distance at Earth's Equivalent Radiation)
: 2.832 AU ( 423604677.6 km)
Outer Boundary (the orbital distance at Mars's Equivalent Radiation)
: 4.315 AU ( 645479785.2 km)
Snow Line (the orbital distance at Snow Line Equivalent Radiation)
: 6.349 AU ( 949851780.6 km)
Radiation at Planetary Boundary of KELT-21 b : 4018124.84 W/m2
(Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star KELT-21)
Kopparapu Recent Venus for Star KELT-21 distance : 1.937 AU
Kopparapu Runaway Greenhouse for Earth-sized planet for Star KELT-21 distance : 2.453 AU
Kopparapu Runaway Greenhouse for Super-Earth-sized planet for Star KELT-21 distance : 2.369 AU
Kopparapu Runaway Greenhouse for Mars-sized planet for Star KELT-21 distance : 2.593 AU
Kopparapu Outer Boundary for Maximum Greenhouse for Star KELT-21 distance : 4.230 AU
Kopparapu Outer Boundary for Early Mars for Star KELT-21 distance : 4.460 AU
(Habitable zone calculated based on Kopparapu et al.(2013) around the star KELT-21)
Original Kopparapu Recent Venus for Star KELT-21 distance : 2.009 AU
Original Kopparapu Runaway Greenhouse for Star KELT-21 distance : 2.507 AU
Original Kopparapu Moist Greenhouse for Star KELT-21 distance : 2.659 AU
Original Kopparapu Outer Boundary for Maximum Greenhouse for Star KELT-21 distance : 4.306 AU
Original Kopparapu Outer Boundary for Early Mars for Star KELT-21 distance : 4.478 AU
(Habitable zone calculated based on Kopparapu et al.(Original) around the star KELT-21)
(Position in Stellar Map of star KELT-21 and its Exoplanet KELT-21 b)
(Zoomed position in Stellar Map of star KELT-21 and its Exoplanet KELT-21 b (zoom level 3))
(Synthetic Spectrum of star KELT-21*)
*Yamashiki YA et al. 2019 ApJ 881 114
MUSCLES Paper I - France et al. 2016 ApJ 820 89
MUSCLES Paper II- Youngblood et al. 2016 ApJ 824 101
MUSCLES Paper III- Loyd et al. 2016 ApJ 824 102
