Magazine Posts

NASA Astronomy Picture of the Day:

Bright stars, interstellar clouds of dust and glowing nebulae fill this cosmic scene, a skyscape just north of Orion's belt. Close to the plane of our Milky Way Galaxy, the wide field view spans just under 5 degrees or about 10 full moons on the sky. Striking bluish M78, a reflection nebula, is at the lower right. M78's tint is due to dust preferentially reflecting the blue light of hot, young stars. In colorful contrast, the red swath of glowing hydrogen gas streaming through the center is part of the region's faint but extensive emission nebula known as Barnard's Loop. At upper left, a dark dust cloud forms a prominent silhouette cataloged as LDN 1622. While M78 and the complex Barnard's Loop are some 1,500 light-years away, LDN 1622 is likely to be much closer, only about 500 light-years distant from our fair planet Earth.

Photo by Terry Hancock

NASA Astronomy Picture of the Day:

Over fifty gravitational wave events have now been detected. These events mark the distant, violent collisions of two black holes, a black hole and a neutron star, or two neutron stars. Most of the 50 events were detected in 2019 by the LIGO gravitational wave detectors in the USA and the VIRGO detector in Europe. In the featured illustration summarizing the masses of the first 50 events, blue dots indicate higher-mass black holes while orange dots denote lower-mass neutron stars. Astrophysicists are currently uncertain, though, about the nature of events marked in white involving masses that appear to be in the middle -- between two and five solar masses. The night sky in optical light is dominated by nearby and bright planets and stars that have been known since the dawn of humanity. In contrast, the sky in gravitational waves is dominated by distant and dark black holes that have only been known about for less than five years. This contrast is enlightening -- understanding the gravitational wave sky is already reshaping humanity's knowledge not only of star birth and death across the universe, but properties of the universe itself.

NASA Astronomy Picture of the Day:

This is what it looks like to punch an asteroid. Last month, NASA's robotic spacecraft OSIRIS-REx descended toward, thumped into, and then quickly moved away from the small near-Earth asteroid 101955 Bennu. The featured video depicts the Touch-And-Go (TAG) sampling event over a three-hour period. As the movie begins, the automated probe approaches the 500-meter, diamond-shaped, space rock as it rotates noticeably below. About 20 seconds into the video, Nightingale comes into view -- a touchdown area chosen to be relatively flat and devoid of large boulders that could damage the spaceship. At 34 seconds, the shadow of OSIRIS-REx's sampling arm suddenly comes into view, while very soon thereafter rocks and gravel fly from the arm's abrupt hard impact. The wily spacecraft was able to capture and successfully stow some of Bennu's ejecta for return to Earth for a detailed analysis. This long return is scheduled to start in 2021 March with arrival back on Earth in 2023 September. If the return sample does successfully reach Earth, it will be scrutinized for organic compounds that might have seeded a young Earth, rare or unusual elements and minerals, and clues about the early history of our Solar System.

NASA Astronomy Picture of the Day:

What's happening to the Sun? Clearly, the Sun's lower half is hidden behind a thick cloud. Averaging over the entire Earth, clouds block the Sun about 2/3rds of the time, although much less over many land locations. On the Sun's upper right is a prominence of magnetically levitating hot gas. The prominence might seem small but it could easily envelop our Earth and persist for over a month. The featured image is a combination of two exposures, one optimizing the cloud and prominence, and the other optimizing the Sun's texture. Both were taken about an hour apart with the same camera and from the same location in Lynnwood, Washington, USA. The shaggy texture derives from the Sun's chromosphere, an atmospheric layer that stands out in the specifically exposed color. The uniformity of the texture shows the surface to be relatively calm, indicative of a Sun just past the solar minimum in its 11-year cycle. In the years ahead, the Sun will progress toward a more active epoch where sunspots, prominences, and ultimately auroras on Earth will be more common: solar maximum. Gallery: Notable images of the Halloween Blue Moon of 2020 submitted to APOD

Photo by Rainee Colacurcio

NASA Astronomy Picture of the Day:

What's happening at the center of the Trifid Nebula? Three prominent dust lanes that give the Trifid its name all come together. Mountains of opaque dust appear near the bottom, while other dark filaments of dust are visible threaded throughout the nebula. A single massive star visible near the center causes much of the Trifid's glow. The Trifid, cataloged as M20, is only about 300,000 years old, making it among the youngest emission nebulas known. The star forming nebula lies about 9,000 light years away toward the constellation of the Archer (Sagittarius). The region pictured here spans about 10 light years. The featured image is a composite with luminance taken from an image by the 8.2-m ground-based Subaru Telescope, detail provided by the 2.4-m orbiting Hubble Space Telescope, color data provided by Martin Pugh and image assembly and processing provided by Robert Gendler. Portal Universe: Random APOD Generator

NASA Astronomy Picture of the Day:

re extreme and terrifying realms of the Universe tonight. If you dare to look, mysterious dark matter, a graveyard galaxy, zombie worlds, and gamma-ray bursts of doom are not all that awaits. Just follow the link and remember, it's all based on real science, even the scary parts. Have a safe and happy halloween!

NASA Astronomy Picture of the Day:

On Halloween fear and dread will stalk your night skies, also known as Phobos and Deimos the moons of Mars. The 2020 opposition of Mars was on October 13, so the Red Planet will still rise shortly before sunset. Near Halloween's Full Moon on the sky, its strange yellowish glow will outshine other stars throughout the night. But the two tiny Martian moons are very faint and in close orbits, making them hard to spot, even with a small telescope. You can find them in this carefully annotated composite view though. The overexposed planet's glare is reduced and orbital paths for inner moon Phobos and outer moon Deimos are overlayed on digitally combined images captured on October 6. The diminutive moons of Mars were discovered in August of 1877 by astronomer Asaph Hall at the US Naval Observatory using the Great Equatorial 26-inch Alvan Clark refractor

Photo by Dennis Simmons

NASA Astronomy Picture of the Day:

Inspired by the halloween season, this telescopic portrait captures a cosmic cloud with a scary visage. The interstellar scene lies within the dusty expanse of reflection nebula IC 2118 in the constellation Orion, the Hunter. IC 2118 is about 800 light-years from your neighborhood, close to bright bluish star Rigel at Orion's foot. Often identified as the Witch Head nebula for its appearance in a wider field of view it now rises before the witching hour. With spiky stars for eyes, the ghoulish apparition identified here seems to extend an arm many light-years long toward Orion's hot supergiant star. The source of illumination for IC 2118, Rigel is just beyond this frame at the upper left.

Photo by Casey Good/Steve Timmons

NASA Astronomy Picture of the Day:

Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars. The overall blue glow near the inner star forming region results from the emission of ionized hydrogen gas. The surrounding nebula, featured here, holds a complex tapestry of gas, dark dust, stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. NGC 6357 spans about 400 light years and lies about 8,000 light years away toward the constellation of the Scorpion.

Photo by Steven Mohr

NASA Astronomy Picture of the Day:

What would an erupting volcano on Venus look like? Evidence of currently active volcanoes on Venus was announced earlier this year with the unexplained warmth of regions thought to contain only ancient volcanoes. Although large scale images of Venus have been taken with radar, thick sulfuric acid clouds would inhibit the taking of optical light vistas. Nevertheless, an artist's reconstruction of a Venusian volcano erupting is featured. Volcanoes could play an important role in a life cycle on Venus as they could push chemical foods into the cooler upper atmosphere where hungry microbes might float. Pictured, the plume from an erupting volcano billows upwards, while a vast lava field covers part of the hot and cracked surface of Earth's overheated twin. The possibility of airborne microbial Venusians is certainly exciting, but currently controversial. An APOD Described on TikTok: By astrokirsten

NASA Astronomy Picture of the Day:

Do any shapes seem to jump out at you from this interstellar field of stars and dust? The jeweled expanse, filled with faint, starlight-reflecting clouds, drifts through the night in the royal constellation of Cepheus. Far from your own neighborhood on planet Earth, these ghostly apparitions lurk along the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over two light-years across and brighter than the other spooky chimeras, VdB 141 or Sh2-136 is also known as the Ghost Nebula, seen at toward the bottom of the featured image. Within the reflection nebula are the telltale signs of dense cores collapsing in the early stages of star formation.

Photo by Bogdan Jarzyna

NASA Astronomy Picture of the Day:

Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and why visible matter is distributed as it is both in the local universe and on the cosmic microwave background. The featured image from the American Museum of Natural History's Hayden Planetarium previous Space Show Dark Universe highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer simulation, complex filaments of dark matter, shown in black, are strewn about the universe like spider webs, while the relatively rare clumps of familiar baryonic matter are colored orange. These simulations are good statistical matches to astronomical observations. In what is perhaps a scarier turn of events, dark matter -- although quite strange and in an unknown form -- is no longer thought to be the strangest source of gravity in the universe. That honor now falls to dark energy, a more uniform source of repulsive gravity that seems to now dominate the expansion of the entire universe.

Photo by Tom AbelRalf KaehlerKIPACSLACAMNH