Epoch J2000.0 Equinox J2000.0
|Right ascension||07h 18m 29.1316s|
|Declination||−13° 13′ 01.507″|
|Apparent magnitude (V)||11.4|
|U−B color index||-0.47|
|B−V color index||0.28|
|Proper motion (μ)||RA: -3.74 mas/yr
Dec.: 3.52 mas/yr
|Parallax (π)||-0.66 ± 2.55 mas|
(1124 pc)
|Absolute magnitude (MV)||-3.84|
|Age||20 million years|
The distance is uncertain, varying between 3.5 kiloparsecs (11,410 lightyears) and 6.9 kiloparsecs (22,500 light years). Assuming a distance of 4.8 kiloparsecs (15,600 light-years), this star is calculated to be 280.000 times brighter than our Sun, 16 times more massive, and 1.41 times larger with a surface temperature of 112,000 Kelvin.
Stars of its kind are characterised by a rapid loss of stellar mass, driven by chemically enriched high-speed stellar winds. It is estimated that it loses mass at the rate of 7x10−5 solar masses each year through winds of 1,545 km/s.
Studies of the interaction between WR 7 and the surrounding nebula assumes a distance of 5 kiloparsecs, and have discovered the existence of a HI region of 70x37 kiloparsecs that expands at 12 km/s, possibly created by the progenitor of the current star, a type-O main sequence star. It seems likely that there is a bow shock acting on the southern edge of the nebula, possibly reduced when the star was at the stage of red supergiant.
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