CO Eridani
CO Eridani Facts
CO Eridani's star type is eclipsing main sequence star that can be located in the constellation of Eridanus. The description is based on the spectral class.
CO Eridani is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (F7V) of the star, the star's colour is blue to white .
CO Eridani's Alternative Names
CO Eridani has alternative name(s) :- CO Eri, CO Eri.
Location of CO Eridani
The location of the main sequence 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 object is compared to the celestial equator and is expressed in degrees. For CO Eridani, the location is 02h 35m 38.60 and -45° 04` 12.2 .
Proper Motion of CO Eridani
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 -21.94 ± 0.83 milliarcseconds/year towards the north and 34.53 ± 1.06 milliarcseconds/year east if we saw them in the horizon. . When the value is negative then the star and the Sun are getting closer to one another, likewise, a positive number means that two stars are moving away. Its nothing to fear as the stars are so far apart, they won't collide in our life-time, if ever.
Physical Properties (Colour, Temperature) of CO Eridani
CO Eridani Colour and Temperature
CO Eridani has a spectral type of F7V. This means the star is a blue to white main sequence star. The star has a B-V Colour Index of 0.65 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 5,722 Kelvin.
CO Eridani Radius
Radius has been calculated as being 4.42 times bigger than the Sun. The Sun's radius is 695,800km, therefore the star's radius is an estimated 3,078,051.11.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 5.37. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.
CO Eridani Apparent and Absolute Magnitudes
CO Eridani has an apparent magnitude of 9.12 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 1.66 If you used the 2007 Parallax value, you would get an absolute magnitude of 1.24. 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 CO Eridani
Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 3.22 which gave the calculated distance to CO Eridani as 1012.93 light years away from Earth or 310.56 parsecs. It would take a spaceship travelling at the speed of light, 1012.93 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 2.66 which put CO Eridani at a distance of 1226.18 light years or 375.94 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.
Variable Type of CO Eridani
The star is a eclipsing Beta Persei (Algol)/ 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. CO Eridani brightness ranges from a magnitude of 10.300 to a magnitude of 9.200 over its variable period. The smaller the magnitude, the brighter the star.
Additional CO Eridani Facts and Figures
Primary / Proper / Traditional Name CO Eridani
Alternative Names CO Eri, HD 16308, HIP 12071, CO Eri
Spectral Type F7V
Star Type Main Sequence Dwarf Star
Colour Yellow - White
Constellation Eridanus
Proper Motion RA. 34.53 ± 1.06 milliarcseconds/year
Variable Star Class Eclipsing
Variable Star Type Beta Persei (Algol)/
Variable Magnitude Range (Brighter - Dimmer) 9.200 - 10.300
Achernar (Alpha Eridani)
Cursa (Beta Eridani)
Zaurak (Gamma Eridani)
Rana (Delta Eridani)
Ran (Epsilon Eridani)
AS Eridani
BB Eridani
BC Eridani
BM Eridani
BR Eridani