It’s not that hard. See the lights on behind you, pull over and lock your phone.

You need a tripod or something to rest the phone against. The prompt to take an astrophotography photo doesn’t come up until the phone had been held VERY still for 5-10 sec.

Biometrics are fine, just use lockdown of you get pulled over or are going throgh TSA.

You can still activate the camera/camcoder by double tapping power on a Pixel even in lockdown.