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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...

In the far reaches of our solar system beyond the orbit of Neptune, a mysterious and yet-unseen world may be lurking in the darkness. Dubbed “Planet 9,” this hypothetical celestial body has been the subject of intense scientific debate and speculation since its existence was first proposed in 2016. Now, a new study published to the arXiv pre-print service by a team from the California Institute of Technology, Université Côte d’Azur, and Southwest Research Institute has provided compelling evidence supporting the presence of this enigmatic planet. The origin of the Planet 9 hypothesis stems from the peculiar alignments in the...

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...

If there are alien civilizations out there close enough to pick up our stray signals, there's a non-zero chance that amongst the first transmissions, they could receive the opening of the 1936 Olympic Games, meaning our first contact with another species (in the unlikely event that they picked them up) could include a speech by Adolf Hitler. "This wasn't the first broadcast, of course," senior SETI astronomer Seth Shostak explained to RealClearScience. "But it was at a high frequency that might make it through the ionosphere." In the film Contact, this ended up being the first message humanity received from...

An artist’s concept of NASA’s Advanced Composite Solar Sail System spacecraft in orbit. NASA plans to launch the solar sail this week from New Zealand to perform navigation tests, using sunlight to propel it. Image courtesy of NASA/Aero Animation/Ben Schweighart April 22 (UPI) -- NASA is gearing up for a launch this week that will test a new way to navigate the solar system, using a large sail to catch the sunlight. The Advanced Composite Solar Sail System is scheduled to lift off Wednesday in New Zealand aboard a Rocket Lab Electron rocket from NASA's Complex 1 on the Mahia...

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,...

Explanation: Yes, but can your volcano do this? To the surprise of some, Mt. Etna emits, on occasion, smoke rings. Technically known as vortex rings, the walls of the volcano slightly slow the outside of emitted smoke puffs, causing the inside gas to move faster. A circle of low pressure develops so that the emitted puff of volcanic gas and ash loops around in a ring, a familiar geometric structure that can be surprisingly stable as it rises. Smoke rings are quite rare and need a coincidence of the right geometry of the vent, the right speed of ejected smoke,...

Explanation: Watch Juno zoom past Jupiter. NASA's robotic spacecraft Juno is continuing on its now month-long, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 16, the sixteenth time that Juno passed near Jupiter since it arrived in mid-2016. Each perijove passes near a slightly different part of Jupiter's cloud tops. This color-enhanced video has been digitally composed from 21 JunoCam still images, resulting in a 125-fold time-lapse. The video begins with Jupiter rising as Juno approaches from the north. As Juno reaches its closest view -- from about 3,500 kilometers over Jupiter's cloud tops...

Explanation: When the dark shadow of the Moon raced across North America on April 8, sky watchers along the shadow's narrow central path were treated to a total solar eclipse. During the New Moon's shadow play diamonds glistened twice in the eclipse-darkened skies. The transient celestial jewels appeared immediately before and after the total eclipse phase. That's when the rays of a vanishing and then emerging sliver of solar disk are just visible behind the silhouetted Moon's edge, creating the appearance of a shiny diamond set in a dark ring. This dramatic timelapse composite from north-central Arkansas captures both diamond...

Explanation: A jewel of the southern sky, the Great Carina Nebula is more modestly known as NGC 3372. One of our Galaxy's largest star forming regions, it spans over 300 light-years. Like the smaller, more northerly Great Orion Nebula, the Carina Nebula is easily visible to the unaided eye. But at a distance of 7,500 light-years it lies some 5 times farther away. This stunning telescopic view reveals remarkable details of the region's glowing filaments of interstellar gas and obscuring cosmic dust clouds. The Carina Nebula is home to young, extremely massive stars, including the still enigmatic variable Eta Carinae,...

Explanation: From our vantage point in the Milky Way Galaxy, we see NGC 1232 face-on. Nearly 200,000 light-years across, the big, beautiful spiral galaxy is located some 47 million light-years away in the flowing southern constellation of Eridanus. This sharp, multi-color, telescopic image of NGC 1232 includes remarkable details of the distant island universe. From the core outward, the galaxy's colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the grand, sweeping spiral arms. NGC 1232's apparent, small, barred-spiral companion galaxy is cataloged as NGC 1232A....

You never really know what you might find hiding in your own backyard, especially if those things are particularly adept at escaping detection. Just 1,924 light-years from the Solar System, in the constellation of Aquila, astronomers have just discovered a black hole. And it's not just any black hole. Named Gaia BH3, or BH3, the object is the most massive stellar-mass black hole we've ever spotted in the Milky Way, clocking in at a hefty 33 times the mass of the Sun. It's the second-closest black hole we've found to our home-world, and it's just hanging out, quietly in space,...

Explanation: Not one, but two comets appeared near the Sun during last week's total solar eclipse. The expected comet was Comet 12P/Pons-Brooks, but it was disappointingly dimmer than many had hoped. However, relatively unknown Comet SOHO-5008 also appeared in long duration camera exposures. This comet was the 5008th comet identified on images taken by ESA & NASA's Sun-orbiting SOHO spacecraft. Likely much smaller, Comet SOHO-5008 was a sungrazer which disintegrated within hours as it passed too near the Sun. The featured image is not only unusual for capturing two comets during an eclipse, but one of the rare times that...

From the Sciences and Cosmology web page: "Want me to tell you something that will blow your mind or make you lose sleep? Well, look at this picture. Each of those dots you see is a GALAXY... And each GALAXY has roughly 100BILLION STARS. Also, each STAR has at least 1 PLANET. Now how many galaxies do you think there can be in that picture? And this is just a photograph of a very little parcel of the universe. This makes me lose sleep, thinking about how so insignificant we really are. Lol."

Methane plumes are detected by plane at a Georgia landfill surrounded by homes. Photo courtesy of Carbon Mapper April 16 (UPI) -- Far more methane, a potent greenhouse gas, is being released from landfills and oil and gas operations around the world than governments realized, recent airborne and satellite surveys show. That's a problem for the climate as well as human health. It's also why the U.S. government has been tightening regulations on methane leaks and wasteful venting, most recently from oil and gas wells on public lands. The good news is that many of those leaks can be fixed...

Research scientists from Linköping University (LiU) in Sweden say they have created the first two-dimensional single-atom layer of gold using a technique perfected by Japanese smiths over 100 years ago. Dubbed “goldene” in reference to the popular single-atom carbon material graphene that essentially kicked off the 2D materials revolution, the breakthrough material could possess a large number of exotic properties like those found in other single-atom 2D materials. The researchers behind the first-ever accomplishment also say they believe goldene could also offer several immediate applications. These include new methods for harvesting energy, catalysis for hydrogen generation, carbon conversion, water purification,...

Explanation: The explosion is over, but the consequences continue. About eleven thousand years ago, a star in the constellation of Vela could be seen to explode, creating a strange point of light briefly visible to humans living near the beginning of recorded history. The outer layers of the star crashed into the interstellar medium, driving a shock wave that is still visible today. The featured image captures some of that filamentary and gigantic shock in visible light. As gas flies away from the detonated star, it decays and reacts with the interstellar medium, producing light in many different colors and...

Explanation: Something strange happened to this galaxy, but what? Known as the Cigar Galaxy and cataloged as M82, red glowing gas and dust are being cast out from the center. Although this starburst galaxy was surely stirred up by a recent pass near its neighbor, large spiral galaxy M81, this doesn't fully explain the source of the red-glowing outwardly expanding gas and dust. Evidence indicates that this material is being driven out by the combined emerging particle winds of many stars, together creating a galactic superwind. In the featured images, a Hubble Space Telescope image in visible light is shown...

International Thinktank Applied Physics (AP) has released its “Warp Factory” simulator and toolkit to help scientists and engineers move closer to building a real-world Star Trek-style warp drive. Having already established itself in the nascent field of warp mechanics with the previous release of its “physical warp drive” design in 2021, AP is now offering its expertise to the broader community to advance the development of existing and future warp drive concepts. The Public Benefit Corporation is also putting its money where its mouth is by offering warp field theorists a chance at $500,000 worth of grant money, a commitment...

Explanation: How does a total solar eclipse end? Yes, the Moon moves out from fully blocking the Sun, but in the first few seconds of transition, interesting things appear. The first is called a diamond ring. Light might stream between mountains or through relative lowlands around the Moon's edge, as seen from your location, making this sudden first light, when combined with the corona that surrounds the Moon, look like a diamond ring. Within seconds other light streams appear that are called, collectively, Bailey's beads. In the featured video, it may seem that the pink triangular prominence on the Sun...