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rlier this week, Earth’s shadow swept across the full Moon in the year’s only total lunar eclipse. This stunning sequence combines images showing the Moon’s path across the night sky. Each lunar image captures our planet’s shadow gradually engulfing the Moon, culminating in its red glow. Sunlight scatters and refracts as it passes through Earth’s atmosphere toward the Moon. Shorter wavelength light (blue and green) scatters more efficiently, leaving red, orange, and yellow hues to paint the lunar surface. Tsé Bit'a'í (”rock with wings”, also known as Shiprock), located in Navajo Nation, provides a powerful volcanic foreground central to this photo and to stories of Navajo origin, adventure, and heroism. As the first full moon of the lunar new year, this eclipse held significance across cultures. Visible from East Asia to North America, this eclipse united observers across great distances, a cosmic reminder that we share the same sky. Growing Gallery: Total Lunar Eclipse of March 3

What’s looking back at you isn’t a cosmic eye, but Shapley 1, a beautifully symmetric planetary nebula. Shapley 1, also known as the Fine Ring Nebula or PLN 329+2.1, bejewels the southern sky constellation of the Carpenter's Square (Norma). The nebula is the result of a star near the mass of our Sun running out of fuel and shedding its outer layers. Glowing oxygen from those expelled layers makes up the circular halo. The bright central point is actually a binary: a white dwarf, the remaining stellar core after the outer layers are expelled into space, and another star, orbiting each other every 2.9 days. Shapley 1’s annular shape is due to our top-down view of the system and provides insight into the influence of central stars on planetary nebula structures.

If you could fly over the North Pole of Mars, what would you see?  Images from ESA’s Mars Express mission in 2019 were compiled into the featured video which shows just such a trip. First you see below you a landscape tinted orange by rusted iron in the fine soil, with some land appearing darker due to exposed rock. Soon the northern polar cap comes into view, mostly white because of its reflective frozen water. Surrounding the polar cap is the North Polar Basin, a layered depression covered with dust and sand. The frames in the featured video were captured during northern Martian Spring when the carbon-dioxide ice is evaporating, leaving the underlying water-ice in the cap. Mars Express continues to study the Martian surface and look for clues about the Red Planet's ancient climate and potential for life.

How well do you know the night sky? OK, but how well can you identify famous sky objects in a very deep image? Either way, here is a test: see if you can find some well-known night-sky icons in a deep image filled with filaments of normally faint dust and gas. This image contains the Pleiades star cluster, Barnard's Loop, Orion Nebula, Aldebaran, Betelgeuse, Witch Head Nebula, Eridanus Loop, and the California Nebula. To find their real locations, here is an annotated image version. The reason this task might be difficult is similar to the reason it is initially hard to identify familiar constellations in a very dark sky: the tapestry of our night sky has an extremely deep hidden complexity. The featured composite reveals some of this complexity in a 16 hours of sky exposure in dark skies over Granada, Spain. Tonight: Total Lunar Eclipse

How does the Moon's appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse. Stars move by in the background because the Moon orbits the Earth during the eclipse. The circular shadow of the Earth is then seen moving across the Moon. The light blue hue of the shadow's edge is related to why Earth's sky is blue, while the deep red hue of the shadow's center is related to why the Sun appears red when near the horizon. Tomorrow night, people living in Eastern Asia, Australia, and much of North America may get to see a Total Blood Moon Lunar Eclipse. Here the term blood refers to the (likely) red color of a fully eclipsed Moon. Almost Hyperspace: Random APOD Generator

Fans of the western sky after sunset have lately enjoyed this month's remarkable array of bright planets. Witnessed from some locations, on February 18 planet Mercury even appeared to slide behind the Moon, an event known as a lunar occultation. These two snapshots, taken in early evening skies show before and after telescopic views of the rare disappearance of innermost planet behind young Moon. The top panel finds bright Mercury just visible at the northern (right) edge of the earthshine-illuminated lunar disk. In the bottom panel the bright planet has emerged in darker skies beyond the Moon's sunlit crescent. As seen south of Sallisaw, Oklahoma, planet Earth, this lunar occultation of Mercury lasted only about 3 minutes (video). But you can still check out a parade of planets tonight. March 3: Total Lunar Eclipse

Normally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic field of view. Floating in the interstellar sea, the nebula is anchored right and left by two bright stars, Mu and Eta Geminorum, at the foot of the celestial twins. The Jellyfish Nebula itself is right of center, seen as a brighter arcing ridge of emission with dangling tentacles. In fact, this cosmic jellyfish is part of bubble-shaped supernova remnant IC 443, the expanding debris cloud from a massive star that exploded. Light from the explosion first reached planet Earth over 30,000 years ago. Like its cousin in astrophysical waters the Crab Nebula supernova remnant, the Jellyfish Nebula is known to harbor a neutron star, the ultradense remnant of the collapsed stellar core. An emission nebula cataloged as Sharpless 249 fills the field at the upper left. The Jellyfish Nebula is about 5,000 light-years away. At that distance, this image would be about 300 light-years across.

What does the universe look like through infrared goggles? Our eyes can only see visible light, but astronomers want to see more. Today’s APOD shows spiral galaxy IC 5332 as seen by two NASA telescopes: Webb in mid-infrared and Hubble in ultraviolet and visible light. To toggle between the two space-based views just slide your cursor over the image (or follow this link). The Hubble image highlights the spiral arms of the galaxy separated by dark regions, whereas the Webb image reveals a finer, more tangled structure. Interstellar dust scatters and absorbs light from the stars in the galaxy, causing the dark dust lanes in the Hubble image, and then emits heat in infrared light, so dust glows in this Webb image. The Mid-InfraRed Instrument on Webb needs to operate at a chilling temperature of -266ºC (or - 447ºF), otherwise it would detect infrared radiation from the telescope itself. Combining these observations, astronomers connect the “small scale” of gas and stars to the truly large scale of galactic structure and evolution.

ver wonder what it would look like to crack open the Sun? The Egg Nebula, a dying Sun-like star, can unscramble this question. Pictured is a combination of several visible and infrared images of the nebula (also known as RAFGL 2688 or CRL 2688) taken with the Hubble Space Telescope. The star has shed its outer layers, and a bright, hot core (or "yolk") now illuminates the milky "egg white" shells of gas and dust surrounding the center. The central lobes and rings are structures of gas and dust recently ejected into space, with the dust being dense enough to block our view of the stellar core. Light beams emanate from that blocked core, escaping through holes carved in the older ejected material by newer, faster jets expelled from the star’s poles. Astronomers are still trying to figure out what causes the disks, lobes, and jets during this short (only a few thousand years!) phase of the star’s evolution, making this an egg-cellent image to study! APOD Front Page: apod.nasa.gov

Look up this week and see a whole bunch of planets. Just after sunset, looking west (mostly), planets Mercury, Venus, Saturn, and Jupiter will all be visible to the unaided eye simultaneously. If you have a telescope, planets Uranus and Neptune can also be seen. In order up from the horizon, the lineup this week will be Venus (the brightest), Mercury, Saturn, Neptune, Uranus, and Jupiter (second brightest). It doesn't matter where on Earth you live because this early evening planet parade will be visible through clear skies all around the globe. The planets will appear to be nearly in a line because they all orbit the Sun in nearly the same plane: the ecliptic. The featured image shows a similar planet parade that occurred in 2022, captured over the Sydney Opera House in southern Australia. Although visible all week, the planets will be most easily seen together this weekend.

Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured 18-hour exposure, taken from Bory Tucholskie, Poland covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45, the Pleiades lies about 400 light years away toward the constellation of the Bull (Taurus). A common legend with a modern twist is that one of the brighter stars faded since the cluster was named, leaving only six of the sister stars visible to the unaided eye. The actual number of Pleiades stars visible, however, may be more or less than seven, depending on the darkness of the surrounding sky and the clarity of the observer's eyesight. Sky Surprise: What picture did APOD feature on your birthday? (after 1995)