YZ Horolgii is a blue to white pulsating variable star that can be located in the constellation of Horologium. The description is based on the spectral class. YZ Horolgii is not part of the constellation but is within the borders of the constellation.
The star can not be seen by the naked eye, you need a telescope to see it.
HIP14656 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD19817.
YZ Horolgii has alternative name(s) :- , YZ Hor.
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 YZ Horolgii, the location is 03h 09m 22.08 and -48° 57` 46.0 .
YZ Horolgii has a spectral type of F0p (CrEu). This means the star is a blue to white variable star. The star has a B-V Colour Index of 0.33 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 6,656 Kelvin.
YZ Horolgii Radius has been calculated as being 3.19 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 2,223,025.35.km. If you need the diameter of the star, you just need to multiple the radius by 2. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.
YZ Horolgii has an apparent magnitude of 8.15 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. Using the supplied Parallax value, you would get an absolute magnitude of 1.71 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 5.16 which gave the calculated distance to YZ Horolgii as 632.10 light years away from Earth or 193.80 parsecs. It would take a spaceship travelling at the speed of light, 632.10 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.
The star is a pulsating Slow Irregular 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. YZ Horolgii brightness ranges from a magnitude of 8.300 to a magnitude of 8.160 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||YZ Horolgii|
|Alternative Names||HD 19817, HIP 14656, YZ Hor|
|Spectral Type||F0p (CrEu)|
|Constellation's Main Star||No|
|Multiple Star System||Yes|
|Star Type||Variable Star|
|Colour||blue to white|
|Visual / Apparent Magnitude||8.15|
|Naked Eye Visible||Requires a 7x50 Binoculars - Magnitudes|
|Right Ascension (R.A.)||03h 09m 22.08|
|Declination (Dec.)||-48° 57` 46.0|
|Galactic Latitude||-55.65 degrees|
|Galactic Longitude||261.73 degrees|
|Distance from Earth||5.16 Parallax (milliarcseconds)|
|632.10 Light Years|
|39,973,840.91 Astronomical Units|
|Variable Star Class||Pulsating|
|Variable Star Type||Slow Irregular|
|Mean Variability Period in Days||0.108|
|Variable Magnitude Range (Brighter - Dimmer)||8.160 - 8.300|
|Calculated Effective Temperature||6,656 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|