Comet Leonard appears in STEREO telescope

Over the past couple of days, speculation has grown among astronomers that comet Leonard may be undergoing "outbursts" — rapid changes in brightness corresponding to large and abrupt releases of volatile material. However, with the comet close to the horizon in twilight skies, observation from Earth are slightly challenging. Thankfully the NASA STEREO-A satellite has had eyes on the comet since early November, and has watched its every move. In this animation [above/below], we show highly processed images taken by the SECCHI/HI-2 camera on STEREO on Dec. 5-Dec 14, 2021. Over just a few days, we see a dramatic increase in the comet’s brightness and an apparent significant increase in gas production leading to the comet forming a long, flowing ion (gas) tail that interacts strongly with the solar wind, which at least supports the ground-based observations that noted increased activity in the comet.

» A guide to observing the comet.

More of Comet Leonard:

• » C2021_A1_Leonard_HI2A_20211214.mp4 - NASA/NRL/B.Gallagher