Sidusglacies - ⚡️

Saturn Aurora.

Credit: NASA, ESA, J Clarke and Z Levay

Interstellar dust of the Horsehead Nebula as revealed by the Hubble Space Telescope and KUEYEN telescope. Credit: NASA/ESA/Hubble, ESO

Betelgeuse is still there, but had to check

These beautiful Kelvin-Helmholtz clouds were spotted over Lincolnshire on December 19th. They form between two layers of air, one of which is moving faster than the other. Although that situation is not very unusual, the conditions have to be just right for visible clouds to form at that interface between layers, and the clouds themselves are typically short-lived. This set is particularly lovely with its smooth curves and breaking wave form. If you, like me, love these clouds but never manage to see them yourself, you can always try wearing some instead! (Image credit: A. Towriss; via BBC News; submitted by Vince D.)

Space Age landscapes by planetary scientist William K. Hartmann.

The Sun rises over Earth in a postcard illustrated by Soviet cosmonaut Alexei Leonov, recalling the 1965 mission when he became the first human to walk in space.

“One of the most actively changing areas on Mars are the steep edges of the North Polar layered deposits. This image from NASA’s Mars Reconnaissance Orbiter (MRO) shows many new ice blocks compared to an earlier image in December 2006. An animation shows one example, where a section of ice cliff collapsed. The older image (acquired in bin-2 mode) is not as sharp as the newer one.” Credit - nasa.gov