DX Cancri

DX Cancri
DX
Location of DX Cancri in the constellation Cancer

Observation data
Epoch J2000      Equinox J2000
Constellation Cancer
Right ascension 08h 29m 49.35279s
Declination +26° 46′ 33.6241″
Apparent magnitude (V) 14.81
Characteristics
Spectral type M6.5V
Apparent magnitude (J) 8.2
U−B color index +2.11
B−V color index +2.08
Variable type Flare star
Astrometry
Radial velocity (Rv)+9.0 km/s
Proper motion (μ) RA: −1,113.694 mas/yr
Dec.: −612.191 mas/yr
Parallax (π)279.2496±0.0637 mas
Distance11.680 ± 0.003 ly
(3.5810 ± 0.0008 pc)
Absolute magnitude (MV)16.98
Details
Mass0.106±0.009 M
Radius0.1235±0.0006 R
Luminosity0.00073±0.000007 L
Surface gravity (log g)~5 cgs
Temperature2,840 K
Rotation0.46 days
Rotational velocity (v sin i)11.0 km/s
Age200 Myr
Other designations
G 051-015, GCTP 2016.01, GJ 1111, LHS 248
Database references
SIMBADdata

An ultraviolet band light curve for a flare on DX Cancri, adapted from Pettersen (1981)

DX Cancri is a red dwarf star in the northern zodiac constellation of Cancer. It is the 18th closest star (or star system) to the Sun, at a distance of 11.680 light-years (3.581 parsecs) as determined by its parallax. It is also the nearest star in Cancer. Despite this, the star has less than 1% of the Sun's luminosity and, with an apparent visual magnitude of 14.81, is far too faint to be seen with the naked eye. Visually viewing this star requires a telescope with a minimum aperture of 16 in (41 cm).

In 1981, Bjørn Ragnvald Pettersen discovered that the star, then called G 51-15, is a variable star. It was given its variable star designation, DX Cancri, in 1985. It is a flare star that has unpredictable, intermittent increases in brightness by up to a factor of five.

The star has a stellar classification of M6.5V, identifying it as a type of main sequence star known as a red dwarf. Such stars are characterized by their high abundance in the universe, low mass, radius, faint brightness and reddish color. It has about 10% of the mass of the Sun, and 12% of the Sun's radius. The outer envelope of the star has an effective temperature of 2,840 K.

It is a proposed member of the Castor Moving Group of stars that share a common trajectory through space. This group has an estimated age of 200 million years.