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WR 3 - HD9974 - HIP7681

WR 3 is a Wolf-Rayet star that can be located in the constellation of Cassiopeia. HIP7681 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD9974.

Location of WR 3

The location of the star in the galaxy is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the star is compared to the celestial equator and is expressed in degrees. For WR 3, the location is 01h 38m 55.63 and +58d09`22.7 .

Wolf-Rayet Star

The star is a Wolf-Rayet, a rare type of star of which not many are known. These stars are extremely luminous and large compared to our Sun. They live fast and die hard in a matter of millions not billions of years like our Sun. They exhaust their hydrogen supplies, turning to other gasses and expand outwards with massive solar winds, moving a step closer in the stellar evolution towards their death in a super or hypernova explosion.

Physical Properties (Temperature, Radius) of WR 3

WR 3 has a spectral type of WN3+.... This means the star is a Wolf-Rayet star. The star has a B-V Colour Index of 0.01 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 10,051 Kelvin.

WR 3 Apparent and Absolute Magnitudes

WR 3 has an apparent magnitude of 10.67 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. If you used the 1997 Parallax value, you would get an absolute magnitude of Magnitude, whether it be apparent/visual or absolute magnitude is measured by a number, the smaller the number, the brighter the Star is. Our own Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Distance to WR 3

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as -2.80 which gave the calculated distance to WR 3 as -1164.87 light years away from Earth or -357.14 parsecs. It would take a spaceship travelling at the speed of light, -1164.87 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

Source of Information

The source of the information if it has a Hip I.D. is from Simbad, the Hipparcos data library based at the University at Strasbourg, France. Hipparcos was a E.S.A. satellite operation launched in 1989 for four years. The items in red are values that I've calculated so they could well be wrong. Information regarding Stellar Age, Metallicity or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

WR 3 Facts

Alternative Names

Traditional NameWR 3
Hipparcos Library I.D.7681
Henry Draper Designation9974
Wolf-Rayet Id3

Visual Facts

Star Type Wolf-Rayet star
Apparent Magnitude10.67
Right Ascension (R.A.)01h 38m 55.63
Declination (Dec.)+58d09`22.7
1997 Distance from Earth-2.80 Parallax (milliarcseconds)
 -1164.87 Light Years
 -357.14 Parsecs
B-V Index0.01
Spectral TypeWN3+...

Estimated Facts

Calculated Effective Temperature10,051 Kelvin

Sources and Links

SIMBAD SourceLink

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