9 Sagittae is a blue eclipsing binary system variable star that can be located in the constellation of Sagitta. 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.
The Id of the star in the Yale Bright Star Catalogue is HR7574. HIP97796 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD188001.
9 Sagittae has alternative name(s) :- , QZ Sge.
Flamsteed designations are named after the creator, Sir John Flamsteed. Sir John numbered the stars in the constellation with a number and the latin name, this star's Flamsteed designation is 9 Sagittae with it shortened to 9 Sge.
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+18 4276.
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 9 Sagittae, the location is 19h 52m 21.77 and +18° 40` 18.8 .
9 Sagittae has a spectral type of O8e. This means the star is a blue variable star. The star has a B-V Colour Index of -0.03 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 11,122 Kelvin.
9 Sagittae Radius has been calculated as being 61.75 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 42,962,572.75.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. The star's Iron Abundance is -0.11 with an error value of 9.99 Fe/H with the Sun has a value of 1 to put it into context.
9 Sagittae has an apparent magnitude of 6.24 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 -6.95 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 0.23 which gave the calculated distance to 9 Sagittae as 14181.01 light years away from Earth or 4347.83 parsecs. It would take a spaceship travelling at the speed of light, 14181.01 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.
The star is a eclipsing binary system Eclipsing 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. 9 Sagittae brightness ranges from a magnitude of 6.256 to a magnitude of 6.207 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.0 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||9 Sagittae|
|Alternative Names||HD 188001, HIP 97796, HR 7574, 9 Sge, BD+18 4276, QZ Sge|
|Multiple Star System||No / Unknown|
|Star Type||Variable Star|
|Visual / Apparent Magnitude||6.24|
|Naked Eye Visible||Yes - Magnitudes|
|Right Ascension (R.A.)||19h 52m 21.77|
|Declination (Dec.)||+18° 40` 18.8|
|Galactic Latitude||-4.33 degrees|
|Galactic Longitude||56.48 degrees|
|Distance from Earth||0.23 Parallax (milliarcseconds)|
|14181.01 Light Years|
|Radial Velocity||13.60 ± 2.30 km/s|
|Iron Abundance||-0.11 ± 9.99 Fe/H|
|Variable Star Class||Eclipsing binary system|
|Variable Star Type||Eclipsing|
|Mean Variability Period in Days||0.037|
|Variable Magnitude Range (Brighter - Dimmer)||6.207 - 6.256|
|Calculated Effective Temperature||11,122 Kelvin|