Exoplanet Name : |
eta2 Hyi b |
Alternate Name : |
HD 11977 b |
Status : |
Confirmed |
Radius (Rjup / Re): |
0.9078 |
(Rjup) |
10.1759 |
(Rearth) |
Mass (Mjup / Me): |
6.2900 |
(Mjup) |
1999.8300 |
(Mearth) |
Semi Major Axis / Orbital Distance Calculated |
1.8900 |
(AU) |
1.8900 |
(AU Est.) |
Eccentricity : |
0.4000 |
Orbital Period(Yrs) |
1.9466 |
Orbital Period(Observed/Estimated) |
711.00 |
(Days Obs.) |
686.70 |
(Days Est.) |
Surface Gravity (G Earth) |
19.3130 |
Star Radiation at Atmospheric Boundary: |
35541.9 |
(W/m2) |
Measured Temperature (K) |
0.0 |
(K) |
Blackbody T 0.1(K) |
612.8 |
(K) |
Blackbody T 0.3(K) |
575.5 |
(K) |
Blackbody T 0.7(K) |
465.6 |
(K) |
Tidally Locked Blackbody T 0.1(K) |
728.8 |
(K) |
Tidally Locked Blackbody T 0.3(K) |
684.4 |
(K) |
Size Class: |
Jupiter-size |
Mass Class: |
|
Detection Type : |
Radial Velocity |
Mass Detection : |
|
Radius Detection : |
|
Habitability by Solar Eq. Astronomical Unit: |
Not habitable |
Habitability by Kopparapu: |
Not habitable |
Star Name : |
eta2 Hyi |
Alternate Name : |
HD 11977 |
Star Distance(LY) : |
216.9 |
Stellar Radius(Rsun) : |
13.0 |
(Rsun Measured) |
Stellar Mass(Msun) : |
1.9 |
(Msun Measured) |
1.8 |
(Msun Estimated) |
Star Age : |
1.2 |
(GY) |
Temperature : |
4975 |
(K) |
Spectral type : |
G8.5 III |
UV portion[%]: |
3.1 |
Visible portion[%]: |
36.8 |
IR portion[%]: |
60.1 |
Metalicity : |
-0.2 |
Absolute Magnitude: |
0.6 |
Apparent Magnitude: |
4.7 |
Right Ascension(RA) |
28.7333 |
Declination (DEC) |
-67.6472 |
Hubble Space Telescope Guide Star Catalog (GSC) ID |
|
Discovered by |
|
Discovery Paper - Authors |
|
Discovery Paper - Title |
|
Discovery Paper - Journal |
|
Discovery Paper - URL |
|
SIMBAD LINK |
|
Open Exoplanet Database Link |
|
![](eta2_Hyi_b_CSun.png) |
![](eta2_Hyi_b_CJup.png) |
![](eta2_Hyi_b_CNep.png) |
![](eta2_Hyi_b_CEar.png) |
/
eta2 Hyi b
eta2 Hyi b
eta2 Hyi b is an exoplanet orbiting the star eta2 Hyi, located about 216.9 light-years (66.5 pc) away from Solar System. Its discovery was publicly announced on 2005.
The host star eta2 Hyi has apparent magnitude of 4.7, with absolute magnitude of 0.6. It is 1.9 times more massive and 13.0 times bigger compared with our Sun. The surface temperature is 4975 with its spectral types of G8.5 III
In this planetary system, the extrasolar planet eta2 Hyi b orbits around the star eta2 Hyi every 711.0 days with its orbital distance of 1.89 AU ( 282739975.6 km)
(Projected orbit of eta2 Hyi b around its host star eta2 Hyi)
![](eta2_Hyi_b_Orb.png)
The Star eta2 Hyi 's habitable zone is located at the following distance
Inner Boundary (the orbital distance at Venus's Equivalent Radiation )
: 6.970 AU ( 1042767855.1 km)
Earth Boundary (the orbital distance at Earth's Equivalent Radiation)
: 9.635 AU ( 1441377683.6 km)
Outer Boundary (the orbital distance at Mars's Equivalent Radiation)
: 14.682 AU ( 2196340613.6 km)
Snow Line (the orbital distance at Snow Line Equivalent Radiation)
: 21.605 AU ( 3232011428.5 km)
Radiation at Planetary Boundary of eta2 Hyi b : 35541.87 W/m2
(Habitable zone calculated based on SEAU(Solar Equivalent Astronomical Unit) around the star eta2 Hyi)
![](eta2_Hyi_b_OrbH.png)
Kopparapu Recent Venus for Star eta2 Hyi distance : 7.549 AU
Kopparapu Runaway Greenhouse for Earth-sized planet for Star eta2 Hyi distance : 9.558 AU
Kopparapu Runaway Greenhouse for Super-Earth-sized planet for Star eta2 Hyi distance : 9.232 AU
Kopparapu Runaway Greenhouse for Mars-sized planet for Star eta2 Hyi distance : 10.132 AU
Kopparapu Outer Boundary for Maximum Greenhouse for Star eta2 Hyi distance : 17.342 AU
Kopparapu Outer Boundary for Early Mars for Star eta2 Hyi distance : 18.292 AU
(Habitable zone calculated based on Kopparapu et al.(2013) around the star eta2 Hyi)
![](eta2_Hyi_b_OrbK.png)
Original Kopparapu Recent Venus for Star eta2 Hyi distance : 7.468 AU
Original Kopparapu Runaway Greenhouse for Star eta2 Hyi distance : 9.851 AU
Original Kopparapu Moist Greenhouse for Star eta2 Hyi distance : 9.882 AU
Original Kopparapu Outer Boundary for Maximum Greenhouse for Star eta2 Hyi distance : 17.632 AU
Original Kopparapu Outer Boundary for Early Mars for Star eta2 Hyi distance : 18.337 AU
(Habitable zone calculated based on Kopparapu et al.(Original) around the star eta2 Hyi)
![](eta2_Hyi_b_OrbKO.png)
(Position in Stellar Map of star eta2 Hyi and its Exoplanet eta2 Hyi b)
![](eta2_Hyi_b_STZ0.png)
(Zoomed position in Stellar Map of star eta2 Hyi and its Exoplanet eta2 Hyi b (zoom level 3))
![](eta2_Hyi_b_STZ3.png)
(Synthetic Spectrum of star eta2 Hyi*)
![](eta2_Hyi_b_Spc.png)
*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