Observation data EpochJ2000 EquinoxJ2000 | |
---|---|
Constellation | Auriga |
Right ascension | 04h 55m 59.38527s[1] |
Declination | +30° 34′ 01.5190″[1] |
Apparent magnitude (V) | 9.30[2] |
Characteristics | |
Spectral type | G2IIIne[2] |
B−Vcolor index | +0.74[3] |
Variable type | T Tauri |
Astrometry | |
Radial velocity (Rv) | 23.20[4] km/s |
Proper motion (μ) | RA: 1.18[1]mas/yr Dec.: -22.24[1]mas/yr |
Parallax (π) | 6.85±2.23 mas[1] |
Distance | approx. 500 ly (approx. 150 pc) |
Absolute magnitude (MV) | +2.83[3] |
Details[3] | |
Mass | 2.0±0.1 M☉ |
Radius | 2.61+0.20 −0.23 R☉ |
Luminosity | 6.3±1.6 L☉ |
Surface gravity (log g) | 3.91+0.07 −0.10 cgs |
Temperature | 5550±100 K |
Rotation | 1.76+0.29 −0.33 days |
Rotational velocity (v sin i) | 66.2 km/s |
Age | 4 Myr |
Other designations | |
SU Aur,BD+30° 743,HD 282624,HIP 22925,SAO 57509 | |
Database references | |
SIMBAD | data |
SU Aurigae is aT Tauri-typevariablestar in theconstellationAuriga. It is located about 500light-years (150parsecs) away in theTaurus-Auriga Star Forming Region. Itsapparent magnitude is 9.30, which is dim enough that it cannot be seen with the unaided eye.
In 1907,Henrietta Swan Leavitt discovered that SU Aurigae is a variable star.[5]
SU Aurigae'sspectral type of G2IIIne means that it is aG-type star with aneffective temperature similar to theSun. The III in the spectral type refers to itsluminosity, which is much higher than normalG-type main sequence stars and would put it in thegiant star class.[6] However, it is only about 4 million years old, which is relatively young for a star - youngprotostars like SU Aurigae are luminous because they are larger, not condensing into a normal size until they are older.[7]
SU Aurigae is known to have acircumstellarprotoplanetary disk surrounding it, which is typical of many T Tauri stars.[7] SU Aurigae's disk has a high inclination of 62° and is nearly perpendicular to the plane of sky, so orbitingprotoplanets orcomets may be the cause of why there are drops in the amount of light detected.[3] SU Aurigae'sproper motion and distance is similar toAB Aurigae,[1] a better known pre-main-sequence star, meaning that the two may form a very widebinary system;[6] if not, they are still in the samestar association.