| Observation data Epoch 2000 Equinox 2000 |
|
|---|---|
| Constellation | Lyra |
| Right ascension | 10h 23m 28s |
| Declination | −00° 54′ 08″ |
| Apparent magnitude (V) | 7.38 |
| Distance | 243.8 ± 16.0 ly (74.8 ± 4.9 pc) |
| Spectral type | G5 IV |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Extrasolar Planets Encyclopaedia |
data |
24 Sextantis (often shortened to 24 Sex) is a 7th magnitude star located approximately 244 light-years away in the constellation of Sextans. It is a G-type subgiant with 54% more mass than the Sun, but cooler. At the age of 2.7 billion years, it indicates that it is an evolved A-type star. At a magnitude of 7.38, this star is too faint to be seen with the naked eye, but binoculars would be needed to see this star.
The star is known to have two giant extrasolar planets.
On July 26, 2010 the California and Carnegie Planet Search team announced the discovery of two planets around 24 Sextantis along with two planets around HD 200964.[1] The inner planet is twice as massive as Jupiter and takes 453 days to orbit the star in a circular orbit at the average distance of 1.33 AU (199 Gm). The outer planet is 5/6 the mass of Jupiter and takes 883 days to orbit eccentrically around the star at the average distance of 2.08 AU (312 Gm).
The two planets are in a 2:1 resonance, meaning that the outer planet orbits the star once every time when the inner planet orbits the star twice. These two jovian planets are dancing around each other gravitationally.[1]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity |
|---|---|---|---|---|
| b | ≥1.99+0.26 −0.38 MJ |
1.333+0.004 −0.009 |
452.8+2.1 −4.5 |
0.09+0.14 −0.06 |
| c | ≥0.86+0.35 −0.26 MJ |
2.08+0.05 −0.02 |
883+32 −14 |
0.29+0.16 −0.09 |