V762 Cassiopeiae is a red pulsating variable star that can be located in the constellation of Cassiopeia. The description is based on the spectral class. The star can be seen with the naked eye, that is, you don't need a telescope/binoculars to see it.
This star`s spectral type is recorded in the original Hipparcos data files as being K1V however, the star is displayed below as being "M3 D" making it a red dwarf. If you see it referred to as a K1V then its using older data where as Simbad has a different value and presumed to be more up to date.
V762 Cassiopeiae was at one time regarded as being the furthest star you can see with the naked eye. Any further you`ll need either a binocular or telescope. In 2007, the parallax, the figure that is used to calculate the distance became larger and therefore its distance was calculated as being much closer. It is no longer seen as being the furthest visible. Further Reading: Armagh Observatory
Its been pointed out to me that a star that is a dwarf star would not be able to be seen at that distance, the star is more likely a giant and not a dwarf star as identified by the "M3 D" spectral type. Spectral Type "M3 D" just refers to the colour and not the size. A M star according to the Harvard Classification is a small star. Being a giant then would enable it to be visible in the night sky. The radius of the star is calculated using a formula from SDSS rather than the figure coming from any professional publications or acknowledged source. It is therefore a large variable star which fits more in with it being a giant star rather than a dwarf star. Thanks to Geoff of New Mexico for his help on this.
Its apparent magnitude is 5.87, just slightly brighter than the maximum 6.0 mag that we can see with the naked eye. The largest star in the galaxy so far discovered UY Scuti has a large magnitude of 11.20 which is why we can`t see without telescopic support.
HIP5926 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD7389.
V762 Cassiopeiae has alternative name(s) :- , V762 Cas.
BD number is the number that the star was filed under in the Durchmusterung or Bonner Durchmusterung, a star catalogue that was put together by the Bonn Observatory between 1859 to 1903. The star's BD Number is BD+70 90.
More details on star alternative names can be found at Star Names .
The location of the star in the night sky 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 V762 Cassiopeiae, the location is 01h 16m 11.90 and +71° 44` 37.8 .
All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving -0.50 ± 0.32 miliarcseconds/year towards the north and -0.95 ± 0.45 miliarcseconds/year east if we saw them in the horizon. The Radial Velocity, that is the speed at which the star is moving away/towards us is -17.00000 km/s with an error of about 2.90 km/s .
V762 Cassiopeiae has a spectral type of M3 D. This means the star is a red variable star. The star has a B-V Colour Index of 2 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 1,830 Kelvin.
V762 Cassiopeiae Radius has been calculated as being 2,831.87 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 1,970,418,592.86.km. If you need the diameter of the star, you just need to multiple the radius by 2. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 527.28. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.
V762 Cassiopeiae has an apparent magnitude of 5.87 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 -7.42 If you used the 2007 Parallax value, you would get an absolute magnitude of -3.77. 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.
Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 0.22 which gave the calculated distance to V762 Cassiopeiae as 14825.61 light years away from Earth or 4545.45 parsecs. It would take a spaceship travelling at the speed of light, 14825.61 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.
In 2007, Hipparcos data was revised with a new parallax of 1.18 which put V762 Cassiopeiae at a distance of 2764.10 light years or 847.46 parsecs. It should not be taken as though the star is moving closer or further away from us. It is purely that the distance was recalculated.
The star is a pulsating Semi-Regular Star which are giants or supergiants of intermediate and late spectral variable type which means that its size changes over time. The Variable Type is usually named after the first star of that type to be spotted. V762 Cassiopeiae brightness ranges from a magnitude of 6.020 to a magnitude of 5.920 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.1 days (variability).
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 Metallicity and/or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.
|Primary / Proper / Traditional Name||V762 Cassiopeiae|
|Alternative Names||HD 7389, HIP 5926, BD+70 90, V762 Cas|
|Spectral Type||M3 D|
|Multiple Star System||Yes|
|Star Type||Variable Star|
|Absolute Magnitude||-7.42 / -3.77|
|Visual / Apparent Magnitude||5.87|
|Naked Eye Visible||Yes - Magnitudes|
|Right Ascension (R.A.)||01h 16m 11.90|
|Declination (Dec.)||+71° 44` 37.8|
|Galactic Latitude||8.97 degrees|
|Galactic Longitude||124.89 degrees|
|1997 Distance from Earth||0.22 Parallax (milliarcseconds)|
|14825.61 Light Years|
|2007 Distance from Earth||1.18 Parallax (milliarcseconds)|
|2764.10 Light Years|
|Proper Motion Dec.||-0.50 ± 0.32 milliarcseconds/year|
|Proper Motion RA.||-0.95 ± 0.45 milliarcseconds/year|
|Radial Velocity||-17.00 ± 2.90 km/s|
|Variable Star Class||Pulsating|
|Variable Star Type||Semi-Regular Star which are giants or supergiants of intermediate and late spectral|
|Mean Variability Period in Days||0.083|
|Variable Magnitude Range (Brighter - Dimmer)||5.920 - 6.020|
|Calculated Effective Temperature||1,830 Kelvin|
The star has been identified as being a multi-star system, one in which there is at least one star in close orbit to another star or two or more stars orbiting a central point. The stars may be of equal mass, unequal mass where one star is stronger than the other or be in groups orbiting a central point which doesn't necessarily have to be a star. More information can be found on my dedicated multiple star systems page. The source of the info is Simbad. The file is dated 2000 so any differences between this and any other source will be down to the actual source from where the information came from.
|Proper Motion mas/yr|
|H.D. Id||B.D. Id||Star Code||Magnitude||R.A.||Dec.||Spectrum||Colour||Year|