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Explanation: Thor not only has his own day (Thursday), but a helmet in the heavens. Popularly called Thor's Helmet, NGC 2359 is a hat-shaped cosmic cloud with wing-like appendages. Heroically sized even for a Norse god, Thor's Helmet is about 30 light-years across. In fact, the cosmic head-covering is more like an interstellar bubble, blown by a fast wind from the bright, massive star near the bubble's center. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. NGC 2359 is located about 15,000 light-years away toward...

Explanation: This was a very unusual type of solar eclipse. Typically, it is the Earth's Moon that eclipses the Sun. In 2012, though, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun. Eventually the alignment became perfect and the phase of Venus dropped to zero. The dark spot of Venus crossed our parent star. The situation could technically be labeled a Venusian annular eclipse with an extraordinarily large ring of fire. Pictured here during the occultation, the Sun...

Explanation: On March 14 the Moon was Full. In an appropriate celebration of Pi day, that put the Moon 3.14 radians (180 degrees) in ecliptic longitude from the Sun in planet Earth's sky. As a bonus for fans of Pi and the night sky, on that date the Moon also passed directly through Earth's umbral shadow in a total lunar eclipse. In clear skies, the colors of an eclipsed Moon can be vivid. Reflecting the deeply reddened sunlight scattered into Earth's shadow, the darkened lunar disk was recorded in this time series composite image from Cerro Tololo Observatory, Chile. The...

Explanation: What phase of the Moon is 3.14 radians from the Sun? The Full Moon, of course. Even though the Moon might look full for several days, the Moon is truly at its full phase when it is Pi radians (aka 180 degrees) from the Sun in ecliptic longitude. That's opposite the Sun in planet Earth's sky. Rising as the Sun set on March 9, 2020, only an hour or so after the moment of its full phase, this orange tinted and slightly flattened Moon still looked full. It was photographed opposite the setting Sun from Teide National Park on...

Explanation: Two protostars are hidden in a single pixel near the center of a striking hourglass-shaped nebula in this near-infrared image from the James Webb Space Telescope. The actively forming star system lies in a dusty molecular cloud cataloged as Lynds 483, some 650 light-years distant toward the constellation Serpens Cauda. Responsible for the stunning bipolar outflows, the collapsing protostars have been blasting out collimated energetic jets of material over tens of thousands of years. Webb's high-resolution view shows the violence of star-formation in dramatic detail as twisting shock fronts expand and collide with slower, denser material. The premier close-up...

Explanation: Why does this galaxy look like a curly vegetable? The Fiddlehead spiral galaxy likely gets its distorted spiral appearance from a gravitational interaction with its close-by elliptical companion NGC 770, seen just below. Cataloged as NGC 772 and Arp 78, the Fiddlehead spans over 200,000 light years, is a nearby 100 million light years beyond the stars of our Milky Way galaxy, and is visible toward the constellation of the Ram (Aries). But in the featured image, the Fiddlehead appears to have another companion -- one with a long and fuzzy tail: Comet 43P/Wolf-Harrington. Though the comet appears to...

Explanation: Many spiral galaxies have bars across their centers. Even our own Milky Way Galaxy is thought to have a modest central bar. Prominently barred spiral galaxy NGC 1672, featured here, was captured in spectacular detail in an image taken by the orbiting Hubble Space Telescope. Visible are dark filamentary dust lanes, young clusters of bright blue stars, red emission nebulas of glowing hydrogen gas, a long bright bar of stars across the center, and a bright active nucleus that likely houses a supermassive black hole. Light takes about 60 million years to reach us from NGC 1672, which spans...

Explanation: Could Queen Calafia's mythical island exist in space? Perhaps not, but by chance the outline of this molecular space cloud echoes the outline of the state of California, USA. Our Sun has its home within the Milky Way's Orion Arm, only about 1,000 light-years from the California Nebula. Also known as NGC 1499, the classic emission nebula is around 100 light-years long. On the featured image, the most prominent glow of the California Nebula is the red light characteristic of hydrogen atoms recombining with long lost electrons, stripped away (ionized) by energetic starlight. The star most likely providing the...

Explanation: Why are there so many cyclones around the north pole of Jupiter? The topic is still being researched. NASA's robotic Juno mission orbiting Jupiter took data in 2018 that was used to construct this stunning view of the curious cyclones at Jupiter's north pole. Measuring the thermal emission from Jovian cloud tops, the infrared observations are not restricted to the hemisphere illuminated by sunlight. They reveal eight cyclonic features that surround a cyclone about 4,000 kilometers in diameter, just offset from the giant planet's geographic north pole. Similar data show a cyclone at the Jovian south pole with five...

Explanation: The plane of our Milky Way galaxy extends beyond the limb of planet Earth in this space age exposure captured by astronaut Don Pettit. His camera, with low light and long duration settings, was pointed out the window of a Dragon crew spacecraft docked with the International Space Station on January 29. The orbital outpost was at an altitude of about 400 kilometers above the Pacific Ocean at the time. Motion blurs the Earth below, while the gorgeous view from low Earth orbit includes the Milky Way's prominent satellite galaxies, known as the Large and Small Magellanic Clouds, near...

Explanation: Very faint planetary nebula Abell 7 is about 1,800 light-years distant. It lies just south of Orion in planet Earth's skies toward the constellation Lepus, The Hare. Surrounded by Milky Way stars and near the line-of-sight to distant background galaxies its generally simple spherical shape, about 8 light-years in diameter, is revealed in this deep telescopic image. Within the cosmic cloud are beautiful and complex structures though, enhanced by the use of long exposures and narrowband filters that capture emission from hydrogen, sulfur, and oxygen atoms. Otherwise Abell 7 would be much too faint to be appreciated by eye....

Explanation: Beautiful island universe Messier 94 lies a mere 15 million light-years distant in the northern constellation of the hunting dogs, Canes Venatici. A popular target for earth-based astronomers, the face-on spiral galaxy is about 30,000 light-years across, with spiral arms sweeping through the outskirts of its broad disk. But this Hubble Space Telescope field of view spans about 7,000 light-years or so across M94's central region. The sharp close-up examines the galaxy's compact, bright nucleus and prominent inner dust lanes, surrounded by a remarkable bluish ring of young, massive stars. The massive stars in the ring appear to be...

Explanation: On the right, dressed in blue, is the Pleiades. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and most easily visible open clusters on the sky. The Pleiades contains over 3,000 stars, is about 400 light years away, and only 13 light years across. Surrounding the stars is a spectacular blue reflection nebula made of fine dust. A common legend is that one of the brighter stars faded since the cluster was named. On the left, shining in red, is the California Nebula. Named for its shape, the California Nebula is much...

Explanation: Why does this Moon look so unusual? A key reason is its vivid red color. The color is caused by the deflection of blue light by Earth's atmosphere -- the same reason that the daytime sky appears blue. The Moon also appears unusually distorted. Its strange structuring is an optical effect arising from layers in the Earth's atmosphere that refract light differently due to sudden differences in temperature or pressure. A third reason the Moon looks so unusual is that there is, by chance, an airplane flying in front. The featured picturesque gibbous Moon was captured about two weeks...

Explanation: There's a new lander on the Moon. Yesterday Firefly Aerospace's Blue Ghost executed the first-ever successful commercial lunar landing. During its planned 60-day mission, Blue Ghost will deploy several NASA-commissioned scientific instruments, including PlanetVac which captures lunar dust after creating a small whirlwind of gas. Blue Ghost will also host the telescope LEXI that captures X-ray images of the Earth's magnetosphere. LEXI data should enable a better understanding of how Earth's magnetic field protects the Earth from the Sun's wind and flares. Pictured, the shadow of the Blue Ghost lander is visible on the cratered lunar surface, while the...

Explanation: Have you heard about the Hubble Ultra-Deep Field? Either way, you've likely not heard about it like this -- please run your cursor over the featured image and listen! The Hubble Ultra-Deep Field (HUDF) was created in 2003-2004 with the Hubble Space Telescope staring for a long time toward near-empty space so that distant, faint galaxies would become visible. One of the most famous images in astronomy, the HUDF is featured here in a vibrant way -- with sonified distances. Pointing to a galaxy will play a note that indicates its approximate redshift. Because redshifts shift light toward the...

Explanation: With spacecraft thrusters at top center, the rugged surface of the Moon lies below the Blue Ghost lander in this space age video frame. The view of the lunar far side was captured by the Firefly Aerospace lunar lander on February 24, following a maneuver to circularize its orbit about 100 kilometers above the lunar surface. The robotic lunar lander is scheduled to touch down tomorrow, Sunday, March 2, at 3:34am Eastern Time in the Mare Crisium impact basin on the lunar near side. In support of the Artemis campaign, Blue Ghost is set to deliver science and technology...

Explanation: Planet Earth hangs in the background of this space age selfie. The snapshot was captured by the IM-2 Nova-C lander Athena, just after stage separation following its February 26 launch to the Moon. A tall robotic lander, Athena is scheduled to touch down on Thursday, March 6, in Mons Mouton, a plateau near the Moon’s South Pole. The intended landing site is in the central portion of one of the Artemis 3 potential landing regions. Athena carries rovers and experiments as part of NASA's Commercial Lunar Payload Services program, including a drill intended to explore beneath the lunar surface...

Explanation: Framed in this single, starry, telescopic field of view are two open star clusters, M35 and NGC 2158. Located within the boundaries of the constellation Gemini, they do appear to be side by side. Its stars concentrated toward the upper right, M35 is relatively nearby, though. M35 (also cataloged as NGC 2168) is a mere 2800 light-years distant, with 400 or so stars spread out over a volume about 30 light-years across. Bright blue stars frequently distinguish younger open clusters like M35, whose age is estimated at 150 million years. At lower left, NGC 2158 is about four times...

Explanation: Do you see the ring? If you look very closely at the center of the featured galaxy NGC 6505, a ring becomes evident. It is the gravity of NGC 6505, the nearby (z = 0.042) elliptical galaxy that you can easily see, that is magnifying and distorting the image of a distant galaxy into a complete circle. To create a complete Einstein ring there must be perfect alignment of the nearby galaxy's center and part of the background galaxy. Analysis of this ring and the multiple images of the background galaxy help to determine the mass and fraction of...