It's difficult to say what precise altitude it was at, but the spiral formation is from the final booster stage jettisoning fuel so that it doesn't explode on r

It's difficult to say what precise altitude it was at, but the spiral formation is from the final booster stage jettisoning fuel so that it doesn't explode on re-entry. That means, in very broad terms, the spacecraft and the booster were likely in the low earth orbit regime, and likely just under orbital velocity for the spacecraft. Given that the spiral had a northward azimuth from Delta Junction (as per the article) the draining happened after it had already passed overhead, and it was likely very far away when it actually re-entered. At an inclination in line with Vandenburg, it likely landed in the Pacific. I am an astrodynamicist but my work in launch dynamics is a bit rusty, so bear with me if my off-the-cuff estimates are off.