Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Andromeda |
Right ascension | 00h 01m 26.9169s [1] |
Declination | 39° 23′ 01.7821″ [1] |
Apparent magnitude (V) | 10.63 |
Characteristics | |
Evolutionary stage | main-sequence star |
Spectral type | F [2] |
Astrometry | |
Radial velocity (Rv) | 1.296 [3] km/s |
Proper motion (μ) |
RA: -9.696
[3]
mas/
yr Dec.: -7.823 [3] mas/ yr |
Parallax (π) | 3.6836 ± 0.0144 mas [3] |
Distance | 885 ± 3
ly (271 ± 1 pc) |
Position (relative to KELT-1) [2] | |
Component | KELT-1B |
Epoch of observation | 2012 |
Angular distance | 0.588±0.001 ″ |
Position angle | 157.4±0.2° |
Projected separation | 154±8 AU |
Details [2] | |
Mass | 1.324±0.026 M☉ |
Radius | 1.462+0.037 −0.024 R☉ |
Luminosity | 3.11±0.05 [4] L☉ |
Surface gravity (log g) | 4.229+0.012 −0.019 cgs |
Temperature | 6518±50 K |
Metallicity [Fe/H] | 0.008±0.073 dex |
Rotational velocity (v sin i) | 55 km/s |
Age | 1.75±0.25 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
KELT-1 is a F-type main-sequence star. Its surface temperature is 6518±50 K. It is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of 0.008±0.073, but is much younger at an age of 1.75±0.25 billion years. The star is rotating very rapidly. [2]
A red dwarf stellar companion at a projected separation of 154±8 AU was detected in 2012, simultaneously with a planetary companion. [2]
The star was found to be orbited by a low-mass brown dwarf or giant planet in 2012. [2]
The atmosphere of the brown dwarf
KELT-1b has been extensively measured from space- and ground-based observatories by a team of astronomers led by Thomas Beatty. They found that KELT-1b has an equilibrium temperature of 2422+32
−26
K,
[2] but features a very strong contrast between measured dayside and nightside temperatures. Dayside temperature appears to be 3340±110
K,
[5] while nightside temperature is 1173+175
−130
K.
[6] The excess dayside temperature may be an artifact arising from highly reflective (dayside albedo reaching 0.5, which is unusual for hot planets and brown dwarfs) rock-vapor clouds. Also, the brightest band is shifted eastward from the
subsolar point by 18.3±7.4°.
[5]
KELT-1b's density of 22.1+5.62
−9.16 g/cm3 is the highest among well characterized planets.
[4]
The planetary orbit is well aligned with the equatorial plane of the star, with the misalignment angle equal to 2±16°. [2] Despite the short orbital period, orbital decay of KELT-1b has not been detected as of 2018. [7]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 27.23+0.50 −0.48 MJ |
0.02466±0.00016 | 1.21749397 | 0 | 85.3+2.9 −2.6 ° |
1.15+0.10 −0.15 RJ |