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In two weeks' time, the European Southern Observatory (ESO) is going to present the world with new information about our Milky Way. It's anyone's guess what the announcement will be, but based on what we know of their recent efforts, there's reason to get excited – the results being presented are from the Event Horizon Telescope (EHT) project, which was responsible for producing the first-ever image of a black hole in 2019. For years now the EHT project has been studying the heart of our home galaxy, the Milky Way, which is most likely home to a supermassive black hole...

Explanation: What's happened to the Sun? Two days ago, parts of South America were treated to a partial solar eclipse -- where the Moon blocked out part of the Sun. The featured image shows an image of the partially eclipsed Sun through clouds as it was setting over Patagonia, Argentina. In the tilted image, Earth is toward the right. During the eclipse, the Moon moved partly between Earth and the Sun. Although a visually impressive sight, the slight dimming of surroundings during this partial eclipse was less noticeable than dimming created by a thick cloud. In about two weeks, all...

Explanation: What does a black hole look like? To find out, radio telescopes from around the Earth coordinated observations of black holes with the largest known event horizons on the sky. Alone, black holes are just black, but these monster attractors are known to be surrounded by glowing gas. This first image resolves the area around the black hole at the center of galaxy M87 on a scale below that expected for its event horizon. Pictured, the dark central region is not the event horizon, but rather the black hole's shadow -- the central region of emitting gas darkened by...

Explanation: A mere 600 light-years away, M44 is one of the closest star clusters to our solar system. Also known as the Praesepe or the Beehive cluster its stars are young though, about 600 million years old compared to our Sun's 4.5 billion years. Based on similar ages and motion through space, M44 and the even closer Hyades star cluster in Taurus are thought to have been born together in the same large molecular cloud. An open cluster spanning some 15 light-years, M44 holds 1,000 stars or so and covers about 3 full moons (1.5 degrees) on the sky in...

Look up in the sky at the right moment this weekend and you could see two of the solar system's brightest planets almost touching. Venus and Jupiter will be millions of miles apart, but from Earth they will appear close to colliding. This planetary conjunction happens annually but this year they will appear much closer than usual. The same spectacle won't occur again like this until 2039. Just the naked eye or binoculars should be enough to see it in a clear sky. After Saturday, the two planets will go their separate ways as they drift apart in the coming...

Explanation: Sharp telescopic views of NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this portrait of the magnificent, edge-on spiral galaxy puts some astronomers in mind of its popular moniker, the Hamburger Galaxy. It also reveals a small galaxy nearby (below), likely a satellite of NGC 3628, and a very faint but extensive tidal tail. The drawn out tail stretches for about 300,000 light-years, even beyond the upper left edge of the frame. NGC 3628 shares its neighborhood in the local universe with two other large spirals M65 and M66 in a grouping otherwise...

Explanation: In the early hours of April 24 this bright Lyrid meteor flashed along the central Milky Way. For a moment, it cast a bright reflection across Lake Nian, Yunnan province, China. The annual Lyrid meteor shower, one of the oldest known, is active in late April, as our fair planet plows through dust left along the orbit of long-period comet Thatcher. The trail of the bright fireball points back toward the shower's radiant in the constellation Lyra high in the northern springtime sky and off the top of the frame. Just rising in that starry sky, light from a...

Alignment of NASA’s James Webb Space Telescope is now complete. After full review, the observatory has been confirmed to be capable of capturing crisp, well-focused images with each of its four powerful onboard science instruments. Upon completing the seventh and final stage of telescope alignment, the team held a set of key decision meetings and unanimously agreed that Webb is ready to move forward into its next and final series of preparations, known as science instrument commissioning. This process will take about two months before scientific operations begin in the summer.The alignment of the telescope across all of Webb’s instruments...

Loud fireball spotted over southern Mississippi mostly heard, hardly seen. A fiery meteor streaked across the morning skies in southern Mississippi yesterday, April 27, 2022. More than 30 eyewitnesses in the states of Arkansas, Louisiana, and Mississippi reported seeing a bright fireball at 8:03 a.m. CDT. The sighting was soon followed by numerous reports of loud booms heard in Claiborne County, Mississippi, and surrounding counties. Approximately 22,000 miles out in space, NOAA’s Geostationary Lightning Mappers (GLM) onboard the Geostationary Operational Environmental Satellites (GOES) 16 and 17 detected several bright flashes associated with the fragmentation of this bolide, or exceptionally bright...

The first solar eclipse of 2022 arrives this week across parts of the Southern Hemisphere — here's how you can watch the event live online from other parts of the world. On April 30, a partial solar eclipse will be visible over parts of Antarctica, South America and the Pacific and Atlantic oceans. While skygazers in the U.S. won't get to see the partial solar eclipse in person, they can watch a livestream of the celestial event online. The partial solar eclipse of April 2022 will first be visible at 2:45 p.m. EDT (1845 GMT). The maximum eclipse will happen...

Explanation: What is that large dark spot on Jupiter? It's the shadow of Ganymede, Jupiter's largest moon. When Jupiter's moons cross between the Jovian giant and the Sun, they created shadows just like when the Earth's moon crosses between the Earth and the Sun. Also like on Earth, if you were in a dark shadow on Jupiter, you would see a moon completely eclipse the Sun. Unlike on Earth, moon shadows occur most days on Jupiter -- what's more unusual is that a spacecraft was close enough to record one with a high-resolution image. That spacecraft, Juno, was passing so...

Illustration of an asteroid. (NASA/JPL/Caltech) A gigantic "potentially hazardous" asteroid that may be twice the size of the Empire State Building is set to zoom past Earth Thursday (April 28), according to NASA. The asteroid, named 418135 (2008 AG33), has an estimated diameter between 1,150 and 2,560 feet (350 to 780 meters) and will break into Earth's orbit at a blistering 23,300 mph (37,400 km/h). Thankfully, the asteroid is expected to skim past our planet without any risk of impact. At its closest point, the asteroid – traveling at more than 30 times the speed of sound – will come...

The asteroid, named 418135 (2008 AG33), has an estimated diameter between 1,150 and 2,560 feet (350 to 780 meters) and will break into Earth's orbit at a blistering 23,300 mph (37,400 km/h). Thankfully, the asteroid is expected to skim past our planet without any risk of impact. At its closest point, the asteroid — traveling at more than 30 times the speed of sound — will come within about 2 million miles (3.2 million kilometers) of Earth, which is roughly eight times the average distance between Earth and the moon. This may sound like a big gap, but by cosmic...

Explanation: The world is waking up to a picturesque planet parade. Just before dawn, the eastern skies over much of planet Earth are decorated by a notable line of familiar planets. In much of Earth's northern hemisphere, this line of planets appears most nearly horizontal, but in much of Earth's southern hemisphere, the line appears more nearly vertical. Pictured over the Sydney Opera House in southern Australia, the planet line was captured nearly vertical about five days ago. From top to bottom, the morning planets are Saturn, Mars, Venus, and Jupiter. As April ends, the angular distance between Venus and...

The Webb Space Telescope is in its final (seventh) stage of alignment, bringing the superlative spacecraft tantalizingly close to commencing its scientific operations. Webb, in an artist’s rendering.Illustration: NASA GSFC/CIL/Adriana Manrique Gutierrez This alignment stage involves final tweaks to the telescope’s primary mirrors and is happening right on schedule, four months after the spacecraft’s launch from French Guiana. Unlike the earlier alignment stages, each of which had a specifically outlined goal—stacking images of a specific star, for example—the seventh (and final) stage merely repeats certain checks made previously, to ensure everything is as precise as possible. Meanwhile, the crucial Mid-Infrared...

Explanation: In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebulas. The Keyhole Nebula (NGC 3324), the bright structure just below the image center, houses several of these massive stars. The entire Carina Nebula, captured here, spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina. Eta Carinae, the most energetic star in the nebula, was one of the brightest stars in the sky in the 1830s, but...

Does time exist? The answer to this question may seem obvious: Of course it does! Just look at a calendar or a clock. But developments in physics suggest the non-existence of time is an open possibility, and one that we should take seriously. How can that be, and what would it mean? It'll take a little while to explain, but don't worry: Even if time doesn't exist, our lives will go on as usual. A crisis in physics Physics is in crisis. For the past century or so, we have explained the Universe with two wildly successful physical theories: general...

Explanation: Just now, before you hit the button, two future universes are possible. After pressing the button, though, you will live in only one. A real-web version of the famous Schrödinger's cat experiment clicking the red button in the featured astronaut image should transform that image into a picture of the same astronaut holding one of two cats -- one living, or one dead. The timing of your click, combined with the wiring of your brain and the millisecond timing of your device, will all conspire together to create a result dominated, potentially, by the randomness of quantum mechanics. Some...

Subatomic particles paint pictures of inner worlds of pyramids, volcanoes and more illustration of muon particles raining down on the Great Pyramid of Giza - An invisible rain of the subatomic particles called muons pierces structures on Earth’s surface, including the Great Pyramid of Giza. Those muons can help map out the chambers within the pyramid and have even revealed an unexplained hidden void. Inside Egypt’s Great Pyramid of Giza lies a mysterious cavity, its void unseen by any living human, its surface untouched by modern hands. But luckily, scientists are no longer limited by human senses. To feel out...

The two marsquakes differ in some important ways. S0976a is characterized by only low frequency energy, like many of the quakes identified so far on the planet, while S1000a has a very broad frequency spectrum. "[S1000a] is a clear outlier in our catalog and will be key to our further understanding of Martian seismology," Horleston said. S0976a is likely to have a much deeper origin than S1000a, she noted. "The latter event has a frequency spectrum much more like a family of events that we observe that have been modeled as shallow, crustal quakes, so this event may have occurred...