Autor: Tobias Hoffmann

On the 2nd of March at 20:05 (UTC) the GHOST telescope of the university observatory of Oldenburg (G01) discovered its first Near-Earth Object (NEO) since the start of observations for NEOs in July 2021 [1].* The telescope was one of the first ones that observed the object “2022 EX” or “K22E00X”, after the ATLAS telescope on Mauna Loa (T08), Hawaii, initially found the objects about 12 hours prior at 07:35 (UTC). In total the telescope in Oldenburg was the fifth telescope world-wide that observed the object. With a visual magnitude of 18.2 mag it was a relativly bright NEO, thus more than 20 observatories observed the object in the first two days.

2022 EX is considered a “Potentially Hazardous Asteroid” (PHA) with a size of about 170 m and a minimal orbital intersection distance with Earth of 0.01858 AU (2.8 Million km or about 7 moon distances) [2]. Eventhough it is currently not considered a risk according to the ESA risk list [3], since to current measurements it will not hit Earth in the future, it should be observed frequently to improve the predictions [4], this is why the Oldenburg telescopes are observing the object as long as it is close and bright enough [5].

Since launch of the NEO observation system in Oldenburg, both telescopes of the university observatory, GHOST and ORT, made more than 500 follow-up observations of small objects in the solar system. They submit their measurements to Minor Planet Center (MPC), which combines measurements from observatories all around the world and calculates precise orbits of these objects. This ensures that all objects that could be dangerous for Earth are tracked.

*The Oldenburg telescope did not initially discover the asteroid. It was found by the survey telescope T08 on Hawaii, but the GHOST telescope quickly made decisive verification measurements. The MPC recognizes the first observations that contributed to the essential orbit determination as a discovery.

[1] https://www.minorplanetcenter.net/mpec/K22/K22E59.html

[2] https://www.minorplanetcenter.net/db_search/show_object?utf8=%E2%9C%93&object_id=K22E00X

[3] https://neo.ssa.esa.int/risk-list

[4] https://neo.ssa.esa.int/priority-list

[5] https://www.minorplanetcenter.net/mpec/K22/K22EA5.html

GHOST Telescope (https://wp.uni-oldenburg.de/asf/ghost/) on the roof of the university during the capture of Near-Earth Objects (NEOs) with Star-constellations (e.g., Orion) in the background.