June
1st Moon. Best 60% of 68 images, 0.17 sec, OIII filter Crop of Mare Imbrium There are two distinctive craters in Mare Imbrium, Helicon and Le Verrier. I had a look at the smaller craters Le Verrier A, B, C etc, to see the smallest ones I could detect. Le Verrier X is 3km across There is a 3.6 km crater just below Le Verrier which I can also just about make out. (image from Wikipedia) The Moon was 362133km away at the time of the image. A 3km crater subtends an angle of 1.7 arc seconds at this distance. The images are at 0.87arc seconds per pixel, so it looks like I will struggle to detect anything much smaller than Le Verrier X. June 23rd Quasar PS1 J161737.78+595020.1 This is now the most distant object I have imaged. It has a redshift of 4.351 which puts it at 12.299 billion light years. This is the time of light travel - universe expansion means the quasar is now at 24.572 billion light years distance from us. Astrometry confirms the objects location: June 25th Supernova in M85 I had retired for the night and then saw on Twitter that there was a reported supernova in galaxy M85. The sky was cloudy, mostly thin high level stuff and I could only get two 600 second images. The SN was visible, only just. The magnitude was 17.0 It has since been classified as a type 1a supernova |