Mag 21.7 Quasar in Virgo

Decided to go Quasar hunting. Conditions were very good this evening (or rather as good as it gets here... NELM 4 -4.25 at zenith), low humidity

Managed to get down to mag 21.7 using short exposures 10x25s (average stack) using the Ultrastar mono x2 binned. This was using the C8 at F5. No LP filter.

The NGC4666 (Superwind field is littered with Quasars). I identified and marked 3 but there are more in the image.

The most distant one in the image that I marked is barely visible and required an aggressive stretch. It has a magnitude of 21.7 and a redshift of 2.25 which means light from that quasar has been traveling for ~11.6 billion light years. If you take into account the expansion of space time the distance today would be ~19 billion light years. Pretty much incomprehensible scale.

The mag 21.7 quasar is at the limit of detection using this sensor and short exposures. The pixel size makes a big difference in the ability to go deep. With x2 bin the Ultrastar Mono has large 13 micron pixels which are able to capture very faint electromagnetic flux.