Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Camelopardalis |
Right ascension | 03h 59m 18.2863s[2] |
Declination | +57° 14′ 13.673″[2] |
Apparent magnitude (V) | 9.80 - 10.15[3] |
Characteristics | |
Spectral type | O6nn[4] (O6V((f)) + O6V((f))[5]) |
U−B color index | −0.66[4] |
B−V color index | +0.28[4] |
Variable type | Ellipsoidal[3] |
Astrometry | |
Radial velocity (Rv) | −47[1] km/s |
Proper motion (μ) | RA: −2.3[6] mas/yr Dec.: −0.3[6] mas/yr |
Parallax (π) | 0.1333 ± 0.0789 mas[7] |
Distance | ~4,000[1] pc |
Absolute magnitude (MV) | −4.1[4] |
Orbit[1] | |
Period (P) | 1.175 days |
Semi-major axis (a) | 19.24 R☉ |
Eccentricity (e) | 0 |
Inclination (i) | 62.59° |
Argument of periastron (ω) (secondary) | 90° |
Argument of periastron (ω) (primary) | 270° |
Semi-amplitude (K1) (primary) | 335 km/s |
Semi-amplitude (K2) (secondary) | 400 km/s |
Details[1] | |
A | |
Mass | 37.7 M☉ |
Radius | 7.60 R☉ |
Surface gravity (log g) | 4.251 cgs |
Temperature | 42,000 ± 1,500 K |
Rotational velocity (v sin i) | 290 km/s |
B | |
Mass | 31.6 M☉ |
Radius | 7.01 R☉ |
Surface gravity (log g) | 4.245 cgs |
Temperature | 39,000 ± 1,500 K |
Rotational velocity (v sin i) | 268 km/s |
Other designations | |
MY Camelopardalis, BD+56°864, Alicante 1 NM 693, 2MASS J03591829+5714137, Gaia DR2 469715181320008960, TYC 3725-498-1 | |
Database references | |
SIMBAD | data |
MY Camelopardalis (MY Cam) is a binary star system located in the Alicante 1 open cluster, some 13 kly (4.0 kpc) away in the constellation Camelopardalis. It is one of the most massive known binary star systems and a leading candidate for a massive star merger. MY Cam is the brightest star in Alicante 1.[1]
The system consists of two hot blue O-type stars with one component having a mass of 32 solar masses and the other 38 solar masses. MY Cam is a contact binary and eclipsing binary, with an orbital period of 1.2 days, and an orbital velocity of 1,000,000 km/h (280 km/s; 620,000 mph).[1] Both stars share a common envelope.[1]
GaiaDR2
was invoked but never defined (see the help page).