Starship Asterisk*

Which is more problematic for astronomers; artificial ground lighting or orbiting space vehicles and junk?

Appearing with the massive hexagon and center vortex are a few other features or artifacts in the false-color map-projected video image that are not mentioned/explained. 1) A small dark speck at the very edge of the image ~4 o'clock, 2) A much larger light shaded disk at ~5:30, 3) A light-dark bound...

Today's explanation refers to C/2017 O1 ASASSN as a binary comet. Does this suggest that it has two separate nuclei, only one of which I can resolve in the image posted?

Setting aside discussion of the apparition evoked by today’s amazing aurora image for a moment, I’m intrigued by the “small vertical tail” appearing at the left inner edge of the crescent, just left of image center. May I assume the image captures a dense sheet of incoming electrons more or less edg...

Thank you Art Neuendorffer and JohnD for your replies and helpful references.

If I'm not mistaken, various seismometers have been placed on the Moon over time. Assuming such devices are operable and sensitive enough, is it possible to analyze such seismic readings in order to substantiate the theory that the far side crust is thicker? Would the LCROSS impact at the South Pole...