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23 Aquilae, HD180972, HIP94885

23 Aquilae is a orange to red giant star that can be located in the constellation of Aquila. 23 Aquilae is the brightest star in Aquila based on the Hipparcos 2007 apparent magnitude. The star can be seen with the naked eye, that is, you don't need a telescope/binoculars to see it.

HIP94885 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD180972. The Id of the star in the Gould Star Catalogue is 35. Stars in the southern hemisphere are more likely to have a Gould Id than the northern hemisphere. For example, there are no Gould classified stars in Ursa Major.

Location of 23 Aquilae

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 23 Aquilae, the location is 19h 18m 32.49 and +01d05`06.3 .

Proper Motion of 23 Aquilae

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 17.47 ± 0.29 miliarcseconds/year towards the north and 12.30 ± 0.51 miliarcseconds/year east if we saw them in the horizon.

Physical Properties (Colour, Temperature, Radius) of 23 Aquilae

23 Aquilae has a spectral type of K2II-IIIvar. This means the star is a orange to red giant star. The star is 7310.00000000 Parsecs from the Galactic Centre or terms of Light Years is 23842.5404464000000000s. The star has a B-V Colour Index of 1.14 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 4,593 Kelvin.

23 Aquilae Radius has been calculated as being 16.47 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 11,460,334.55.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 16.02. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

23 Aquilae Apparent and Absolute Magnitudes

23 Aquilae has an apparent magnitude of 5.10 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 -0.24 If you used the 2007 Parallax value, you would get an absolute magnitude of -0.18. 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 23 Aquilae

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 8.56 which gave the calculated distance to 23 Aquilae as 381.03 light years away from Earth or 116.82 parsecs. It would take a spaceship travelling at the speed of light, 381.03 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 8.79 which put 23 Aquilae at a distance of 371.06 light years or 113.77 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's Galacto-Centric Distance is 7,310.00 Parsecs or 23,842.54 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

Source of Information

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.

23 Aquilae Facts

Alternative Names

Traditional/Proper Name23 Aquilae
Flamsteed Name23 Aquilae
Flamsteed Short Name23 Aql
Hipparcos Library I.D.94885
Bonner DurchmusterungBD+00 4168
Gould I.D.35
Henry Draper Designation180972

Visual Facts

Star Typegiant star
Absolute Magnitude-0.24 / -0.18
Visual / Apparent Magnitude5.10
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)19h 18m 32.49
Declination (Dec.)+01d05`06.3
Galactic Latitude-5.53 degrees
Galactic Longitude37.00 degrees
1997 Distance from Earth8.56 Parallax (milliarcseconds)
 381.03 Light Years
 116.82 Parsecs
2007 Revised Distance from Earth8.79 Parallax (milliarcseconds)
 371.06 Light Years
 113.77 Parsecs
Galacto-Centric Distance23,842.54 Light Years / 7,310.00 Parsecs
Proper Motion Dec.17.47 ± 0.29 milliarcseconds/year
Proper Motion RA.12.30 ± 0.51 milliarcseconds/year
B-V Index1.14
Radial Velocity-23.13 ± 0.19 km/s
Spectral TypeK2II-IIIvar
Colour(K) Orange to Red

Estimated Facts

Calculated Effective Temperature4,593 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Multi-Star System

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. IdB.D. IdStar CodeMagnitudeR.A.Dec.SpectrumColourYear
180972+00 4168.0A5.3000023.0000013.00000K0Orange
B9.300001958
C13.500001958

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