It has a diameter of ca.9km and was discovered on February 25th 1992 by the Spacewatch project at the Kitt Peak-observatoriet in Arizona.
It is named after Norwegian astronomer Tommy Grav.
While studying at the Department of Theoretical Astrophysics in Oslo, he and his team found five new Neptune moons. These are the faintest objects ever observed in the solar system. They invented a completely new method to detect these moons. The team that discovered these new satellites of Neptune includes Holman and Kavelaars, graduate student Tommy Grav (University of Oslo & Harvard-Smithsonian Center for Astrophysics), and undergraduate students Wesley Fraser and Dan Milisavljevic (McMaster University, Hamilton, Ontario, Canada).

https://sv.wikipedia.org/wiki/12309_Tommygrav

https://www.uio.no/forskning/forskningsnytt/apollon/artikler/2004/neptunmaaner.html

Spacewatch is a research project at the University of Arizona led by Dr Robert S. McMillan. The aim is to study the smaller objects in the solar system such as asteroids, comets and many other smaller objects. The Kitt Peak observatory outside Tucson, Arizona is mainly used. The project has led to the discovery of many celestial bodies, including the Kuiper belt object, 20000 Varuna, and two entirely new classes of celestial bodies: Small near-Earth asteroids and distant Centaurs.

Spacewatch was the first with a technique where they used automatic photography of the sky with a CCD camera in a telescope and then examine the result with a computer program to see if anything moves in the images.

According to the Minor Planet Center, the Spacewatch project has discovered 248354 minor planets between 1985 and 2021.
The asteroid 4255 Spacewatch, which was also discovered by the project, is named after the project.

https://sv.wikipedia.org/wiki/Spacewatch

Sun distance (au): 2.645

Time: 01:13UT 2026-09-27 Exp. 43 x 120 sec. IR Pass (685 nm) Filter
Tel: C14 @ f/6.6 Camera ASI 174 MM Mini Mono @ +8°C 1"/pix Paramount GT-1100S
Odd Trondal Obs.code 238 (Uranium). Oslo Norway