Comets moving through real SPHEREx images

These are known comets. JPL Horizons tells us where each one was at the moment each SPHEREx image was taken; we found the images that caught it, cut small boxes out of them and measured the comet ourselves: where it really is, how fast it moves, how big its glowing head (coma) is, and its brightness at each image's own wavelength. Nothing here is a discovery.

where JPL predicts it+ where we measured it

Pause ← → speed slownormalfast markers

Following the comet

Brightness at each image's own wavelength

Every exposure (table)

How the comets were chosen

We started from all 4088 comets in the JPL Small-Body Database, computed where each one was at the mid time of every one of the 1.3 million public SPHEREx images (DR1 + QR3), and kept the images that really contain it (JPL Horizons positions). Then we read small boxes of the brightest predicted cases and kept the comets that are clearly seen.