Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cygnus [1] |
Right ascension | 19h 28m 32.8905s [2] |
Declination | +42° 25′ 45.959″ [2] |
Apparent magnitude (V) | 15.306 [3] |
Characteristics | |
Spectral type | M0V [4] |
Astrometry | |
Radial velocity (Rv) | −26.99±6.00 [2] km/s |
Proper motion (μ) |
RA: −0.463(21)
mas/
yr
[2] Dec.: 11.691(21) mas/ yr [2] |
Parallax (π) | 2.2537 ± 0.0185 mas [2] |
Distance | 1,450 ± 10
ly (444 ± 4 pc) |
Details | |
Mass | 0.684±0.026 [5] M☉ |
Radius | 0.664±0.013 [5] R☉ |
Temperature | 4499±75 [5] K |
Metallicity [Fe/H] | −0.17±0.11 [4] dex |
Rotation | 17.951±0.016 days [6] |
Rotational velocity (v sin i) | 0.6 [3] km/s |
Age | 2.2 [7] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
KIC | data |
Kepler-28 is an M-type main-sequence star about 1,450 light-years (440 parsecs) away in the northern constellation of Cygnus. [2] With an apparent visual magnitude of 15.036, [3] this star is too faint to be seen with the naked eye. It is orbited by two exoplanets.
The two transiting planets of Kepler-28 were discovered in 2011 using the Kepler space telescope, and were confirmed in early 2012. [9] They are both warm sub-Neptune gas planets. [7] The planetary parameters were updated in 2023, with lower values for all of mass, radius, and density compared to previous estimates. [5]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 1.63+0.51 −0.40 M🜨 |
0.062 | 5.91213(17) | <0.08 | — | 1.959+0.043 −0.042 R🜨 |
c | 2.06+0.70 −0.52 M🜨 |
0.081 | 8.98597(27) | 0.017+0.023 −0.014 |
— | 1.857±0.042 R🜨 |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cygnus [1] |
Right ascension | 19h 28m 32.8905s [2] |
Declination | +42° 25′ 45.959″ [2] |
Apparent magnitude (V) | 15.306 [3] |
Characteristics | |
Spectral type | M0V [4] |
Astrometry | |
Radial velocity (Rv) | −26.99±6.00 [2] km/s |
Proper motion (μ) |
RA: −0.463(21)
mas/
yr
[2] Dec.: 11.691(21) mas/ yr [2] |
Parallax (π) | 2.2537 ± 0.0185 mas [2] |
Distance | 1,450 ± 10
ly (444 ± 4 pc) |
Details | |
Mass | 0.684±0.026 [5] M☉ |
Radius | 0.664±0.013 [5] R☉ |
Temperature | 4499±75 [5] K |
Metallicity [Fe/H] | −0.17±0.11 [4] dex |
Rotation | 17.951±0.016 days [6] |
Rotational velocity (v sin i) | 0.6 [3] km/s |
Age | 2.2 [7] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
KIC | data |
Kepler-28 is an M-type main-sequence star about 1,450 light-years (440 parsecs) away in the northern constellation of Cygnus. [2] With an apparent visual magnitude of 15.036, [3] this star is too faint to be seen with the naked eye. It is orbited by two exoplanets.
The two transiting planets of Kepler-28 were discovered in 2011 using the Kepler space telescope, and were confirmed in early 2012. [9] They are both warm sub-Neptune gas planets. [7] The planetary parameters were updated in 2023, with lower values for all of mass, radius, and density compared to previous estimates. [5]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 1.63+0.51 −0.40 M🜨 |
0.062 | 5.91213(17) | <0.08 | — | 1.959+0.043 −0.042 R🜨 |
c | 2.06+0.70 −0.52 M🜨 |
0.081 | 8.98597(27) | 0.017+0.023 −0.014 |
— | 1.857±0.042 R🜨 |