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Explanation: Here comes Comet Leonard. Comet C/2021 A1 (Leonard) was discovered as a faint smudge in January 2021 when it was out past Mars -- but its orbit will take the giant shedding ice-ball into the inner Solar System, passing near both Earth and Venus in December before it swoops around the Sun in early January 2022. Although comets are notoriously hard to predict, some estimations have Comet Leonard brightening to become visible to the unaided eye in December. Comet Leonard was captured just over a week ago already sporting a green-tinged coma and an extended dust tail. The featured...

Explanation: Predawn hours of November 19 found the Moon in partly cloudy skies over Cancun, Mexico. Captured in this telephoto snapshot, the lunar disk is not quite entirely immersed in Earth's dark umbral shadow during a long partial lunar eclipse. The partial eclipse was deep though, deep enough to show the dimmed but reddened light in Earth's shadow. That's a sight often anticipated by fans of total lunar eclipses. Wandering through the constellation Taurus, the eclipsed Moon's dimmer light also made it easier to spot the Pleiades star cluster. The stars of the Seven Sisters share this frame at the...

Explanation: In visible light the stars have been removed from this narrow-band image of NGC 281, a star forming region some 10,000 light-years away toward the constellation Cassiopeia. Stars were digitally added back to the resulting starless image though. But instead of using visible light image data, the stars were added with X-ray data (in purple) from the Chandra X-ray Observatory and infrared data (in red) from the Spitzer Space Telescope. The merged multiwavelength view reveals a multitude of stars in the region's embedded star cluster IC 1590. The young stars are normally hidden in visible light images by the...

Explanation: A photographer in silhouette stands in bright moonlight as the Full Moon rises in this well-planned telephoto image. Of course, the Full Moon is normally the brightest lunar phase. But on November 18/19, the Full Moon's light will be dimmed during a deep partial lunar eclipse seen across much of planet Earth. At maximum eclipse only a few percent of the lunar disk's diameter should remain outside the Earth's dark umbral shadow when the Moon slides close to the shadow's southern edge. Near apogee, the farthest point in its orbit, the Moon's motion will be slow. That should make...

A Nasa engineer has sparked a debate about wages and the costs of living in the US after revealing that she was in the process of applying to part-time jobs at Tiffany & Co and Apple. Kelly, a TikTok user who lives in Houston, Texas, and goes by the username @sexybabypartygirl on TikTok, documented her interview experience with the jewellery brand on the app, where she began: “I am a Nasa engineer and I’m applying for a job at Tiffany, part time. And I have my interview in 40 minutes.”

Explanation: Why doesn't the nearby galaxy create a gravitational lensing effect on the background galaxy? It does, but since both galaxies are so nearby, the angular shift is much smaller than the angular sizes of the galaxies themselves. The featured Hubble image of NGC 3314 shows two large spiral galaxies which happen to line up exactly. The foreground spiral NGC 3314a appears nearly face-on with its pinwheel shape defined by young bright star clusters. Against the glow of the background galaxy NGC 3314b, though, dark swirling lanes of interstellar dust can also be seen tracing the nearer spiral's structure. Both...

Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids -- because shower meteors all appear to come from a radiant toward Gemini. Three dimensionally, however, sand-sized debris expelled from the unusual asteroid 3200 Phaethon follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the constellation of Gemini. Therefore, when Earth crosses this orbit, the radiant point of falling debris...

U.S. officials say Russia destroyed a retired satellite in an anti-satellite weapon test, creating a cloud of debris that prompted the seven-member crew of the International Space Station to take shelter in their Crew Dragon and Soyuz spacecraft early Monday as a precaution. "I'm outraged by this unconscionable action," NASA Administrator Bill Nelson said in a statement.... State Department spokesman Ned Price said the Russian Federation "recklessly conducted a destructive satellite test of a direct ascent anti-satellite missile against one of its own satellites." "The test has so far generated over 1,500 pieces of trackable orbital debris and hundreds of...

Explanation: What happening above that volcano? Something very unusual -- a volcanic light pillar. More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting Sun. Alternatively, other light pillars -- some quite colorful -- have been recorded above street and house lights. This light pillar, though, was illuminated by the red light emitted by the glowing magma of an erupting volcano. The volcano is Italy's Mount Etna, and the featured image was captured with a single shot a few hours after sunset in mid-June. Freezing temperatures above...

Alongside advances in space exploration, we’ve recently seen much time and money invested into technologies that could allow effective space resource utilization. And at the forefront of these efforts has been a laser-sharp focus on finding the best way to produce oxygen on the Moon. In October, the Australian Space Agency and NASA signed a deal to send an Australian-made rover to the Moon under the Artemis program, with a goal to collect lunar rocks that could ultimately provide breathable oxygen on the Moon. Although the Moon does have an atmosphere, it’s very thin and composed mostly of hydrogen, neon,...

Explanation: What is that light in the sky? Perhaps one of humanity's more common questions, an answer may result from a few quick observations. For example -- is it moving or blinking? If so, and if you live near a city, the answer is typically an airplane, since planes are so numerous and so few stars and satellites are bright enough to be seen over the din of artificial city lights. If not, and if you live far from a city, that bright light is likely a planet such as Venus or Mars -- the former of which is constrained...

Explanation: Returning along its 6.4 year orbit, periodic comet Churyumov-Gerasimenko (67P) is caught in this telescopic frame from November 7. Sweeping past background stars in the constellation Gemini the comet's dusty tail stretches toward the upper right to Upsilon Geminorum. Also known as Pollux, Beta Geminorum, Gemini's brightest star, shines just off the upper left edge of the field-of-view. Churyumov-Gerasimenko reached its 2021 perihelion or closest approach to the Sun on November 2. At perigee, its closest approach to planet Earth on November 12, this comet was about 0.42 astronomical units away, though it remains too faint to be seen...

I have carried out a search for Planet 9 in the IRAS data. At the distance range proposed for Planet 9, the signature would be a 60 micron unidentified IRAS point source with an associated nearby source from the IRAS Reject File of sources which received only a single hours-confirmed (HCON) detection. The confirmed source should be detected on the first two HCON passes, but not on the third, while the single HCON should be detected only on the third HCON. I have examined the unidentified sources in three IRAS 60micron catalogues: some can be identified with 2MASS galaxies, Galactic...

Explanation: The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this sharp image shows off...

“Earthgrazers” are fireball meteors with a trajectory so shallow that they skim long distances across the upper atmosphere, NASA says. The fireball appeared Tuesday, Nov. 9, around 6:30 p.m. Eastern Daylight Time, officials say, and was “detected by three NASA meteor cameras in the region.” It entered the atmosphere “at a very shallow angle — only 5 degrees from the horizontal.” In fact, it was flying for so long that NASA had to recalculate its data to determine how far it traveled across the planet. “The meteor was first seen at an altitude of 55 miles above the Georgia town...

Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by interstellar dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This telescopic close-up spans about two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with telltale hints of contrasty red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains...

Explanation: Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood. Just as the setting Sun disappears completely from view, a last glimmer appears startlingly green. The effect is typically visible only from locations with a low, distant horizon, and lasts just a few seconds. A green flash is also visible for a rising Sun, but takes better timing to spot. A dramatic green flash...

As first reported by veteran researcher Douglas Dean Johnson, Sen. Kirsten Gillibrand’s (D-N.Y.) proposed legislation would fundamentally transform the government’s approach to the UFO phenomenon. Indeed, the Gillibrand amendment would shift decades of official, Cold War-induced deflection and obfuscation towards increasingly transparent, objective scientific analysis. *snip* Beyond granting a new, UFO-focused unit robust bureaucratic authorities and access to an array of critical government resources, Gillibrand’s amendment would empower the office’s leadership to initiate and supervise rapid field investigations of UFO encounters. Moreover, the Gillibrand proposal requires that all elements of the Department of Defense and the U.S. intelligence community share...

At the end of the first orbital test flight for its 164-foot Starship, SpaceX envisions a reentry into the atmosphere at speeds approaching Mach 25, or 19, 000 miles per hour, followed by 15 minutes of hypersonic flight. During this time, the spacecraft will hurtle sideways, generating tremendous heat before adjusting to an upright position for a "soft " rocket-powered ocean landing 62 miles north of Kauai. It will sink in the Navy's Pacific Missile Range Facility, according to plans for the historic flight, and join dozens of warships that have gone down over past decades during Navy "sink exercises...

Explanation: Why would you want to fake a universe? For one reason -- to better understand our real universe. Many astronomical projects seeking to learn properties of our universe now start with a robotic telescope taking sequential images of the night sky. Next, sophisticated computer algorithms crunch these digital images to find stars and galaxies and measure their properties. To calibrate these algorithms, it is useful to test them on fake images from a fake universe to see if the algorithms can correctly deduce purposely imprinted properties. The featured mosaic of fake images was created to specifically mimic the images...