I enjoy imaging Near Earth Objects (NEO’s) as reported on the pages of
Spaceweather.
With the skies finally clearing in SE Qld, this gave me the opportunity to attempt NEO 2022 NR which was predicted to pass within 1 Lunar Distance (LD) of planet Earth on 10th July, at around mag 16.
Depending on how fast they move, I have previously been able to record the trails of these objects down to magnitude 16. Any faster, smaller or dimmer and they don’t sprinkle enough photons in one place to create the extended trail, unlike the fixed stars which just keep on pouring their light into the charge wells of the sensor under their fixed location.
I set up on the 9th July as I knew 2022 NR would be moving more slowly, but a 30 sec exposure tracking at the sidereal rate did not reveal a trail as I viewed the image on screen. So I asked the Mount to track on the NEO and after 30 secs, a very faint blip did appear so I increased the exposure to 60 secs and there it was, a stationary coalescence of pixels against the trailed stars in the back ground.
Buoyed by this success, I followed the same process the next evening, Sat 10th July when the NEO would be belting along and lo and behold, once more it made its appearance on the computer screen.
The composite comparison image gives an indication of how the NEO sped up as it reached its closest approach, the rate across the FOV some 3 times faster than the previous evening.
Cheers
Dennis