Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. ...
for a single
star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
in the
equatorial Equatorial may refer to something related to:
*Earth's equator
**the tropics, the Earth's equatorial region
**tropical climate
*the Celestial equator
** equatorial orbit
**equatorial coordinate system
** equatorial mount, of telescopes
* equatorial ...
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The origins of the e ...
of
Aquila
Aquila may refer to:
Arts, entertainment, and media
* ''Aquila'', a series of books by S.P. Somtow
* ''Aquila'', a 1997 book by Andrew Norriss
* ''Aquila'' (children's magazine), a UK-based children's magazine
* ''Aquila'' (journal), an or ...
parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...
shift of this star is , which gives a distance estimate of from Earth. It is drifting closer with a
radial velocity
The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...
of −25 km/s, and displays a relatively high
proper motion
Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more dista ...
, traversing the
celestial sphere
In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, ...
at the rate of per year.
The
stellar classification
In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...
of Mu Aquilae is K3-IIIb Fe0.5, indicating that this is an evolvedgiant star with a mild overabundance of iron appearing in its spectrum. It belongs to a sub-category of giants called the red clump, which means it is generating energy through the fusion of helium at its core. Compared to the Sun, it has 116% of the mass and has expanded to 7.7 times the size. This inflated outer envelope has an
effective temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...
of 4,567 K and is radiating 24.5 times the Sun's luminosity. At this heat, Mu Aquilae glows with the orange hue of a K-type star. It is roughly seven billion years old.