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Explanation: What happens to a star that goes near a black hole? If the star directly impacts a massive black hole, then the star falls in completely -- and everything vanishes. More likely, though, the star goes close enough to have the black hole's gravity pull away its outer layers, or disrupt, the star. Then, most of the star's gas does not fall into the black hole. These stellar tidal disruption events can be as bright as a supernova, and an increasing amount of them are being discovered by automated sky surveys. In the featured artist's illustration, a star has...

Explanation: Despite their resemblance to R2D2, these three are not the droids you're looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in the Atacama Desert region of Chile. The ATs are designed to be used for interferometry, a technique for achieving extremely high resolution observations, in concert with the observatory's 8 meter Very Large Telescope units. A total of four ATs are operational, each fitted with a transporter that moves the telescope along a track allowing different arrays with the large unit telescopes. To work as an interferometer, the light from each telescope is...

Explanation: A mere 280 light-years from Earth, tidally locked, Jupiter-sized exoplanet WASP-43b orbits its parent star once every 0.8 Earth days. That puts it about 2 million kilometers (less than 1/25th the orbital distance of Mercury) from a small, cool sun. Still, on a dayside always facing its parent star, temperatures approach a torrid 2,500 degrees F as measured at infrared wavelengths by the MIRI instrument on board the James Webb Space Telescope. In this illustration of the hot exoplanet's orbit, Webb measurements also show nightside temperatures remain above 1,000 degrees F. That suggests that strong equatorial winds circulate the...

Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. The large galaxy of over 100 billion stars has well-defined spiral arms, similar to our own Milky Way. One of the brightest members of the Virgo Cluster of galaxies, M100, also known as NGC 4321 is 56 million light-years distant toward the well-groomed constellation Coma Berenices. In this telescopic image, the face-on grand design spiral shares a nearly 1 degree wide field-of-view with slightly less conspicuous edge-on spiral NGC 4312 (at upper right). The 21 hour long equivalent exposure from a dark sky...

Explanation: To some, this nebula looks like the head of a fish. However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula's colors were created by adopting the Hubble color palette for mapping narrowband emissions from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805,...

The solar flare is the most powerful eruption from sunspot region R3654 yet. Last night (April 30), the sun released an extremely powerful solar flare triggering widespread radio blackouts across the Pacific region. The flare peaked at 7:46 p.m. EDT (2346 GMT) and ended shortly after at 7:58 p.m. EDT (2358). Solar flares are eruptions from the sun's surface that emit intense bursts of electromagnetic radiation. They are created when magnetic energy builds up in the solar atmosphere and is released. Solar flares are categorized by size into lettered groups, with X-class being the most powerful. Then there are M-class...

It sounds like a dream, but it's true in Antarctica, gold rains from the sky. Tucked in among the glaciers, fiery Mount Erebus is the southernmost active volcano on Earth, providing a bit of heat amid the frozen landscape. The frozen continent features 138 volcanoes, according to a 2017 study, with around nine of them reported as active. With a summit elevation of 12,448 feet (3,794 meters), Mount Erebus is the most well-known. Erebus is one of three volcanoes that form Ross Island, and it's said that it was erupting when it was discovered in 1841 during the voyage of...

Explanation: The star system GK Per is known to be associated with only two of the three nebulas pictured. At 1500 light years distant, Nova Persei 1901 (GK Persei) was the second closest nova yet recorded. At the very center is a white dwarf star, the surviving core of a former Sun-like star. It is surrounded by the circular Firework nebula, gas that was ejected by a thermonuclear explosion on the white dwarf's surface -- a nova -- as recorded in 1901. The red glowing gas surrounding the Firework nebula is the atmosphere that used to surround the central star....

An active volcano in Antarctica is shooting $6,000 in gold dust into the air every single day, NASA’s Earth Observatory revealed last week. The volcano on Mount Erebus spits pockets of gas containing 80 grams of crystallized gold daily, it said. Mount Erebus, is arguably Antarctica’s most famous volcano. It holds the titles of the tallest active volcano on the continent, with its summit reaching 12,448 feet (3,794 meters), and the southernmost active volcano on Earth. Named after the personification of darkness in Greek mythology, Mount Erebus was erupting when Captain Sir James Clark Ross first discovered it in 1841....

Explanation: Three bright objects satisfied seasoned stargazers of the western sky just after sunset earlier this month. The most familiar was the Moon, seen on the upper left in a crescent phase. The rest of the Moon was faintly visible by sunlight first reflected by the Earth. The bright planet Jupiter, the largest planet in the Solar System, is seen to the upper left. Most unusual was Comet 12P/Pons-Brooks, below the Moon and showing a stubby dust tail on the right but an impressive ion tail extending upwards. The featured image, a composite of several images taken consecutively at the...

Explanation: The Ring Nebula (M57) is more complicated than it appears through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula's central star. This composite image includes red light emitted by hydrogen as well as visible and infrared light. The Ring Nebula is an elongated planetary nebula, a type of nebula created when a Sun-like star evolves to throw off its outer atmosphere and become a...

Explanation: If the Sun is up but the sky is dark and the horizon is bright all around, you might be standing in the Moon's shadow during a total eclipse of the Sun. In fact, the all-sky Moon shadow shown in this composited panoramic view was captured from a farm near Shirley, Arkansas, planet Earth. The exposures were made under clear skies during the April 8 total solar eclipse. For that location near the center line of the Moon's shadow track, totality lasted over 4 minutes. Along with the solar corona surrounding the silhouette of the Moon planets and stars...

Explanation: In northern hemisphere spring, bright star Regulus is easy to spot above the eastern horizon. The alpha star of the constellation Leo, Regulus is the spiky star centered in this telescopic field of view. A mere 79 light-years distant, Regulus is a hot, rapidly spinning star that is known to be part of a multiple star system. Not quite lost in the glare, the fuzzy patch just below Regulus is diffuse starlight from small galaxy Leo I. Leo I is a dwarf spheroidal galaxy, a member of the Local Group of galaxies dominated by our Milky Way Galaxy and...

On the cold dead surface of Mars, something remarkable happens each spring. The red planet becomes infested with giant black spiders. At least, that’s what it looks like. In reality, vast fields of dark, spider-like formations become etched into the Red Planet’s landscape. No, they are not alive, nor actually spiders, but instead a geological phenomenon that occurs nowhere else in the solar system. With the recent orbital passes of the European Space Agency’s (ESA) Mars Express and the ExoMars Trace Gas Orbiter (TGO), scientists are now closer than ever to understanding these mysterious features known as “araneiforms.” Araneiforms are...

NASA Administrator Bill Nelson is being mocked for suggesting the far side of the moon is always “dark” and can’t explain why China is interested in exploring that part of the moon. “What do you think the Chinese are trying to get at, at the back side of the moon?” Rep. David Trone (D-MD) asked Nelson at a congressional hearing last week. “They are going to have a lander on the far side of the moon, which is the side which is always in dark. Uh, we’re not planning to go there,” he said.

Explanation: Located some 3 million light-years away in the arms of nearby spiral galaxy M33, giant stellar nursery NGC 604 is about 1,300 light-years across. That's nearly 100 times the size of the Milky Way's Orion Nebula, the closest large star forming region to planet Earth. In fact, among the star forming regions within the Local Group of galaxies, NGC 604 is second in size only to 30 Doradus, also known as the Tarantula Nebula in the Large Magellanic Cloud. Cavernous bubbles and cavities in NGC 604 fill this stunning infrared image from the James Webb Space Telescope's NIRCam. They...

Explanation: How did a star form this beautiful nebula? In the middle of emission nebula NGC 6164 is an unusually massive star. The central star has been compared to an oyster's pearl and an egg protected by the mythical sky dragons of Ara. The star, visible in the center of the featured image and catalogued as HD 148937, is so hot that the ultraviolet light it emits heats up gas that surrounds it. That gas was likely thrown off from the star previously, possibly the result of a gravitational interaction with a looping stellar companion. Expelled material might have been...

Let us start by saying we expect different levels of expertise from different people. Like for instance, if we are talking to a layperson and they indicated they didn’t know the difference between a motion to dismiss and a motion for summary judgment, we wouldn’t bat an eyelash at it. That is a level of ignorance that is just normal and justifiable for people who don’t deal with the law very much. We wouldn’t make fun of a such person for not knowing that or look down on them: We would simply explain the difference. But if a person claims...

Explanation: What created this giant X in the clouds? It was the shadow of contrails illuminated from below. When airplanes fly, humid engine exhaust may form water droplets that might freeze in Earth's cold upper atmosphere. These persistent streams of water and ice scatter light from the Sun above and so appear bright from below. On rare occasions, though, when the Sun is near the horizon, contrails can be lit from below. These contrails cast long shadows upwards, shadows that usually go unseen unless there is a high cloud deck. But that was just the case over Istanbul, Türkiye, earlier...

NASA’s Voyager 1 spacecraft is depicted in this artist’s concept traveling through interstellar space, or the space between stars, which it entered in 2012. Credit: NASA/JPL-Caltech ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ After some inventive sleuthing, the mission team can — for the first time in five months — check the health and status of the most distant human-made object in existence. For the first time since November, NASA’s Voyager 1 spacecraft is returning usable data about the health and status of its onboard engineering systems. The next step is to enable the spacecraft to begin returning science data again. The probe and its twin,...