Hartmut Jahreiß (born 1942) is a German astronomer associated with Astronomisches Rechen-Institut specializing in the study of nearby stars.
His thesis was on the spatial distribution, kinetics and age of stars near the Sun.
[1] Jahreiß soon began work at Astronomisches Rechen-Institut with Wilhelm Gliese, a world-renowned authority on nearby stars.
[4] The Gliese catalog stars are now known by the abbreviation GJ (Gliese–Jahreiß) in recognition of Jahreiß's contribution.
Jahreiß contributed to the Hipparcos catalogs of nearby stars.