HD 189245 is the Henry Draper catalogue designation for a solitary^[11] star in the southern constellation of Sagittarius. It has an apparent visual magnitude of 5.66,^[3] which means it is faintly visible to the naked eye. Parallax measurements from the Hipparcos satellite indicate a distance of 72 light years from the Sun.^[2] It is drifting closer with a heliocentric radial velocity of −13 km/s.^[6]

The stellar classification of this star is F8.5 V Fe−0.6 CH−0.5,^[4] indicating that it is an F-type main sequence star with a spectrum that shows deficiencies in iron (Fe) and methylidyne (CH) in its outer atmosphere. It is a variable star with an active chromosphere and is a source of X-ray emission.^[4][12] HD 189245 is spinning rapidly with a projected rotational velocity of 72.6^[8] km/s. Gyrochronology indicates this is a young star with an estimated age of 500 million years. However, the amount of X-ray emission suggests an even younger star that is roughly 100 million years old.^[5]

The velocity components of HD 189245 indicate that it is a likely member of the AB Doradus moving group of stars, which share a common motion through space. This group has an age of around 50 million years and is centered at a point 98 ly (30 pc) from the Sun.^[13]

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