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NASA Astronomy Picture of the Day:

A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That's twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope's Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light. Webb's field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy's core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy's central bar. Astronomers suspect the gravitational field of NGC 1365's bar plays a crucial role in the galaxy's evolution, funneling gas and dust into a star-forming maelstrom and ultimately feeding material into the active galaxy's central, supermassive black hole.

Trier, Caspar-Olevian-Saal, Trier. Entrance to the Caspar-Olevian-Saal.

Agnes Monkelbaan, CC BY-SA 4.0, via Wikimedia Commons. View source.

Trison Thomas on Unsplash

NASA Astronomy Picture of the Day:

The strangest moon in the Solar System is bright yellow. The featured picture, an attempt to show how Io would appear in the "true colors" perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io's colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes. The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter's other Galilean moons. The resulting friction greatly heats Io's interior, causing molten rock to explode through the surface. Io's volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io's volcanic lava is so hot it glows in the dark.

Giacomo Raibolini painted this image of Saint Sebastian in the likeness of his father, Francesco Francia. Today is Saint Sebastian's feast day in the Catholic Church and Oriental Orthodox Church.

Giacomo Raibolini, Public domain, via Wikimedia Commons. View source.

Victor Rodriguez on Unsplash

NASA Astronomy Picture of the Day:

What powers this unusual nebula? CTB 1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion. The resulting supernova remnant, nicknamed the Medulla Nebula for its brain-like shape, still glows in visible light because of the heat generated by its collision with confining interstellar gas. Why the nebula also glows in X-ray light, though, remains a topic of research. One hypothesis holds that an energetic pulsar was created and powers the nebula with a fast outwardly moving wind. Following this lead, a pulsar was found in radio waves that appears to have been expelled by the supernova explosion at over 1000 kilometers per second. Although the Medulla Nebula appears as large as a full moon, it is so faint that it took 84-hours of exposure with a small telescope in Texas, USA, to create the featured image.

Grain field in the Dernekamp hamlet, Kirchspiel, Dülmen, North Rhine-Westphalia, Germany.

Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons. View source.