1999 RM45

On March 2021 the asteroid 1999 RM45 was reaching its best visibility for InFINNity Deck. This asteroid is approximately 350-750 metres in diameter and had its closest approach at a distance of about 11 light seconds (approximately 7x the Earth-Moon distance).

I had programmed its trajectory in the GM3000HPS mount, which allowed me to follow the asteroid unguided. On 1 March I took a 30 seconds exposure of the part of the sky where the asteroid was expected with adjacent result.

From the image a relative speed of just over 1"/s could be calculated.

The following night I captured the asteroid between 18:53:09 and 19:01:36 UTC using FireCapture and the SkyWatcher Esprit 150ED and ZWO ASI1600 Pro Cool camera combination. Exposure was 5 seconds per frame, the result of which is shown here at a 5fps rate. The asteroid is the faint dot at the centre.