explore | Grilled Cheese

Yes, but have you ever seen a sunrise like this? Here, after initial cloudiness, the Sun appeared to rise in two pieces and during a partial eclipse in 2019, causing the photographer to describe it as the most stunning sunrise of his life. The dark circle near the top of the atmospherically-reddened Sun is the Moon -- but so is the dark peak just below it. This is because along the way, the Earth's atmosphere had a layer of unusually warm air over the sea which acted like a gigantic lens and created a second image. For a normal sunrise or sunset, this rare phenomenon of atmospheric optics is known as the Etruscan vase effect. The featured picture was captured in December 2019 from Al Wakrah, Qatar. Some observers in a narrow band of Earth to the east were able to see a full annular solar eclipse -- where the Moon appears completely surrounded by the background Sun in a ring of fire. The next solar eclipse, also an annular eclipse for well-placed observers, will occur this coming Saturday. APOD editor to speak: in Houghton, Michigan on Thursday, October 12 at 6 pm

The month was July, the place was the Greek island of Crete, and the sky was spectacular. Of course there were the usual stars like Polaris, Vega, and Antares -- and that common asterism everyone knows: the Big Dipper. But this sky was just getting started. The band of the Milky Way Galaxy stunned as it arched across the night like a bridge made of stars and dust but dotted with red nebula like candy. The planets Saturn and Jupiter were so bright you wanted to stop people on the beach and point them out. The air glowed like a rainbow -- but what really grabbed the glory was a comet. Just above the northern horizon, Comet NEOWISE spread its tails like nothing you had ever seen before or might ever see again. Staring in amazement, there was only one thing to do: take a picture. Coverage: NASA's SpaceX Crew-1 Mission

Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo, its galactic disk tilted towards our line of sight. This Hubble close-up of the nearby island universe spans about 24,000 light-years across NGC 6744's central region in a detailed portrait that combines visible light and ultraviolet image data. The giant galaxy's yellowish core is dominated by the visible light from old, cool stars. Beyond the core are pinkish star forming regions and young star clusters scattered along the inner spiral arms. The young star clusters are bright at ultraviolet wavelengths, shown in blue and magenta hues.

What could cause such rays of dark? Dark sky rays were caught in spectacular fashion earlier last month from Pentwater, Michigan, USA, looking west over Lake Michigan. The cause is something surprisingly familiar: shadows. Clouds near the horizon can block sunlight from reflecting off air, making columns outward from the Sun appear unusually dark. Cloud shadows can be thought of as the complement of the more commonly highlighted crepuscular rays, also visible above, where sunlight pours though cloud holes. Sometimes, on the opposite side of the sky, anticrepuscular rays can also be seen.

Rocket launching soon for the StriX Launch 13 mission

Active galaxy NGC 1275 is the central, dominant member of the large and relatively nearby Perseus Cluster of Galaxies. A prodigious source of x-rays and radio emission, NGC 1275 accretes matter as entire galaxies fall into it, ultimately feeding a supermassive black hole at the galaxy's core. This stunning visible light image from the Hubble Space Telescope shows galactic debris and filaments of glowing gas, some up to 20,000 light-years long. The filaments persist in NGC 1275, even though the turmoil of galactic collisions should destroy them. What keeps the filaments together? Recent work indicates that the structures, pushed out from the galaxy's center by the black hole's activity, are held together by magnetic fields. To add x-ray data from the Chandra Observatory and radio data from the Very Large Array to the Hubble image, just slide your cursor over the picture. In the resulting composite, x-rays highlight the shells of hot gas surrounding the center of the galaxy, with radio emission filling giant bubble-shaped cavities. Also known as Perseus A, NGC 1275 spans over 100,000 light years and lies about 230 million light years away.

Light-years across, this suggestive shape known as the Seahorse Nebula appears in silhouette against a rich, luminous background of stars. Seen toward the royal northern constellation of Cepheus, the dusty, obscuring clouds are part of a Milky Way molecular cloud some 1,200 light-years distant. It is also listed as Barnard 150 (B150), one of 182 dark markings of the sky cataloged in the early 20th century by astronomer E. E. Barnard. Packs of low mass stars are forming within from collapsing cores only visible at long infrared wavelengths. Still, colorful stars in Cepheus add to the pretty, galactic skyscape.

This delightfully detailed false color image of Saturn was earmarked to celebrate the 8th anniversary of the orbiting Hubble Space Telescope. The picture is a combination of three images taken in January 1998 and shows the lovely ringed planet in reflected infrared light. Different colors indicated varying heights and compositions of cloud layers generally thought to consist of ammonia ice crystals. The eye-catching rings cast a shadow on Saturn's upper hemisphere, while the bright stripe seen within the left portion of the shadow is infrared sunlight streaming through the large gap in the rings known as the Cassini Division. Two of Saturn's many moons have also put in an appearance, Tethys just beyond the planet's disk at the upper right, and Dione at the lower left.

Framing a bright emission region, this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula, the reddish glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant and 70 light-years across the complex and beautiful nebula blossoms at the center of this composite image. Ultraviolet radiation from young energetic stars at the edge of the Cygnus OB3 association, including O star HDE 227018, ionizes the atoms and powers the emission from the Tulip Nebula. HDE 227018 is the bright star near the center of the nebula. Also framed in the field of view is microquasar Cygnus X-1, one of the strongest X-ray sources in planet Earth's sky. Driven by powerful jets from a black hole accretion disk, its fainter visible curved shock front lies above and right, just beyond the cosmic Tulip's petals

$It was really not about superheroes as on May 6 the much touted Super Moon, the largest Full Moon of 2012, rose over this otherwise peaceful harbor. And no supervillains were present either as boats gently rocked at their moorings near the checkerboard La Perdrix lighthouse on the coast of Brittany, France. But the rise of the Super Moon was preceded by a Green Flash, captured in the first frame of this timelapse video recorded that night. The cropped image of the frame, a two second long exposure, shows the strongly colored flash left of the lighted buoy near picture center. While the Super Moon was enjoyed at locations all around the world, the circumstances that produced the Green Flash were more restrictive. Green flashes for both Sun and Moon are caused by atmospheric refraction enhanced by long, low, sight lines and strong atmospheric temperature gradients often favored by a sea horizon.$

Bright and beautiful spiral galaxy M83 lies a mere twelve million light-years from Earth, toward the headstrong constellation Hydra. Sweeping spiral arms, prominent in visible light images, lend this galaxy its popular moniker -- the Southern Pinwheel. In fact, the spiral arms are still apparent in this Chandra Observatory false-color x-ray image of M83, traced by diffuse, hot, x-ray emitting gas. But more striking in the x-ray image is the galaxy's bright central region. The central emission likely represents even hotter gas created by a sudden burst of massive star formation. Point-like neutron star and black hole x-ray sources, final stages in the life cycles of massive stars, also show a concentration near the center of M83 and offer further evidence for a burst of star formation at this galaxy's core. Light from this burst of star formation would have first reached Earth some 20 million years ago.

The Plane of the Ecliptic is illustrated in this Clementine star tracker camera image which reveals (from right to left) the Moon lit by Earthshine, the Sun's corona rising over the Moon's dark limb, and the planets Saturn, Mars, and Mercury. The ecliptic plane is defined as the imaginary plane containing the Earth's orbit around the Sun. In the course of a year, the Sun's apparent path through the sky lies in this plane. The planetary bodies of our solar system all tend to lie near this plane, since they were formed from the Sun's spinning, flattened, proto-planetary disk. The snapshot above nicely captures a momentary line-up looking out along this fundamental plane of our solar system.

Like a Dali masterpiece, this image of Messier 8 from the NASA/ESA Hubble Space Telescope is both intensely colourful and distinctly surreal. Located in the constellation of Sagittarius (The Archer), this giant cloud of glowing interstellar gas is a stellar nursery that is also known as the Lagoon Nebula. Although the name definitely suits the beauty of this object, “lagoon” does suggest tranquillity and there is nothing placid about the high-energy radiation causing these intricate clouds to glow. The massive stars hiding within the heart of the nebula give off enormous amounts of ultraviolet radiation, ionising the gas and causing it to shine colourfully, as well as sculpting the surrounding nebula into strange shapes. The result is an object around four to five thousand light-years away which, on a clear night, is faintly visible to the naked eye. Since it was first recorded back in the 1747 this object has been photographed and analysed at many different wavelengths. By using...

Here's what a spiral galaxy REALLY looks like. Yesterday, M81 was shown in two colors only, but here we see M81 at its most colorful. In the above picture, note how blue the spiral arms are - this indicates the presence of hot young stars and on-going star formation. Also note the yellow hue of the nucleus, possibly designating a population of older stars many billions of years old. M81 is actually a dominant member of a group of galaxies which includes M82 and several other galaxies. Unlike our Local Group of galaxies, large galaxies in the M81 group are actually colliding. It is possible that M81's interaction with M82 create the density waves which generate M81's spiral structure.