Planetary Picture of the Day
Week of May 12, 2025
The universe is full of wondrous circles and spheres, from sun dogs around the Sun to spiraling galaxies and storms on Jupiter, including all of our planets and the Moon. Enjoy!
Monday, 12 May 2025
Double Halo
Yes, you are seeing double in this beautiful photograph from Josh Dury, taken last week from Mendip Hills in Somerset, UK. This particular phenomenon is called a parhelic circle—an optical phenomenon appearing as a white line at the same altitude as the Sun. Parhelic circles form as beams of sunlight are reflected by vertical or almost vertical hexagonal ice crystals. In rare instances, a complete circle stretches across the sky, which it did here. This image captures a nearly 180-degree portion of the sky, horizon to horizon.
Tuesday, 13 May 2025
Mars' Thin Atmosphere
Did you know that Mars has an atmosphere? It's very thin and not breathable for humans, but it does have wind and can carry dust around the planet. This image, captured by ESA's Mars Express, shows that thin atmosphere, fading away into the darkness of space. Also shown is Promethei Terra, a large region to the east of the massive impact basin Hellas Planitia.
Wednesday, 14 May 2025
Out of this Whirl
The graceful, winding arms of the majestic spiral galaxy M51 (NGC 5194) appear like a grand spiral staircase sweeping through space. They are actually long lanes of stars and gas laced with dust.
This sharpest-ever image, taken in January 2005 with the Advanced Camera for Surveys aboard the NASA/ESA Hubble Space Telescope, illustrates a spiral galaxy's grand design, from its curving spiral arms, where young stars reside, to its yellowish central core, a home of older stars. The galaxy is nicknamed the Whirlpool because of its swirling structure.
The Whirlpool is one of astronomy's galactic darlings. Located approximately 25 million light-years away in the constellation Canes Venatici (the Hunting Dogs), the Whirlpool's beautiful face-on view and closeness to Earth allow astronomers to study a classic spiral galaxy's structure and star-forming processes.
Thursday, 15 May 2025
Lunar Sunrise
Rise and shine! Firefly Aerospace’s Blue Ghost lander captured a stunning sunrise over the lunar surface on March 3. The lander carried ten scientific instruments onboard, all of which operated successfully for a full two weeks. At that time, the lander rotated into lunar night and ran out of battery power.
Friday, 16 May 2025
Southern Storms
Jupiter’s south pole, as seen by NASA’s Juno spacecraft from an altitude of 52,000 kilometers. The oval features are cyclones, up to 1,000 kilometers in diameter. Multiple images taken with the JunoCam instrument on three separate orbits were combined to show all areas in daylight, enhanced color, and stereographic projection.
