Planetary Picture of the Day
Week of February 26, 2024
Dunes on Mars, ridges on Europa, and volcanic paterae on Io.
Monday, February 26, 2024
Tvashtar Paterae on Io
An approximate natural-color view of the volcanic Tvashtar Paterae region of Io, made from images acquired by NASA's Galileo spacecraft on Feb. 22, 2000. For an idea of scale, the dark kidney-shaped patera near the center is about 50 kilometers long and 20 kilometers wide.
Tuesday, February 27, 2024
Cracks and Ridges on Europa
A closeup of Europa's complicated surface from Galileo on its 19th orbit of Jupiter in February 1999. This image shows cracks and ridges on Europa's surface that reveal a detailed geologic history that may be related to changing tidal forces as Europa orbits Jupiter.
Wednesday, February 28, 2024
The Dotted Dunes of Mars
As spring dawns on the Northern Hemisphere of Mars, dunes of sand near the poles begin to defrost. Thinner regions of ice typically thaw first revealing sand whose darkness soaks in sunlight and accelerates the thaw. The process might involve sandy jets exploding through the thinning ice. By summer, the spots expand to encompass the entire dunes which are then completely thawed and dark. The carbon dioxide and water ice sublime in the thin atmosphere directly to gas.
Thursday, February 29, 2024
Micro Snowflake
This is a photomicrograph of a dendrite star snowflake captured with a Scanning Electron Microscope. Enjoy a beautiful image on this Leap Day!
