R40 is a blue very luminous supergiant star that can be located in the constellation of Tucana. The star can not be seen by the naked eye, you need a telescope to see it.
HIP5267 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD6884.
R40 has alternative name(s), SMC V2018.
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 R40, the location is 01h 07m 18.22 and -72d28`03.6 .
Luminosity is the amount of energy that a star pumps out and its relative to the amount that our star, the Sun gives out. The figure of 73000.0000000 that I have given is based on the Spectral Types page that I have found on the Internet. You might find a different figure, one that may have been calculated rather than generalised that I have done. The figure is always the amount times the luminosity of the Sun. It is an imprecise figure because of a number of factors including but not limited to whether the star is a variable star and distance.
R40 has a spectral type of B8Iab:e. This means the star is a blue supergiant star. The star has a B-V Colour Index of 0.09 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 8,573 Kelvin. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.
R40 has an apparent magnitude of 10.27 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.
Using the original Hipparcos data that was released in 1997, the parallax to the star was given as -1.88 which gave the calculated distance to R40 as -1734.91 light years away from Earth or -531.91 parsecs. It would take a spaceship travelling at the speed of light, -1734.91 years to get there. We don't have the technology or spaceship that can carry people over that distance yet. R40 brightness ranges from a magnitude of 10.397 to a magnitude of 10.180 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.2 days (variability).
|Short Name||SMC V2018|
|Hipparcos Library I.D.||5267|
|Henry Draper Designation||6884|
|Star Type||supergiant star|
|Visual / Apparent Magnitude||10.27|
|Naked Eye Visible||Requires a 4.5 - 6 Inch Telescope - Magnitudes|
|Right Ascension (R.A.)||01h 07m 18.22|
|Galactic Latitude||-44.61 degrees|
|Galactic Longitude||301.25 degrees|
|1997 Distance from Earth||-1.88 Parallax (milliarcseconds)|
|-1734.91 Light Years|
|Radial Velocity||170.00 ± 4.70 km/s|
|Mean Variability Period in Days||0.182|
|Variable Magnitude Range (Brighter - Dimmer)||10.180 - 10.397|
|Luminosity (x the Sun)||73,000.0000000|
|Calculated Effective Temperature||8,573 Kelvin|