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Explanation: Ten thousand years ago, before the dawn of recorded human history, a new light would suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was from a supernova, or exploding star, and record the expanding debris cloud as the Veil Nebula, a supernova remnant. This sharp telescopic view is centered on a western segment of the Veil Nebula cataloged as NGC 6960 but less formally known as the Witch's Broom Nebula. Blasted out in the cataclysmic explosion, an interstellar shock wave plows through space sweeping up and exciting interstellar material....

Explanation: A new visitor from the outer Solar System, comet C/2025 R2 (SWAN) also known as SWAN25B was only discovered late last week, on September 11. That's just a day before the comet reached perihelion, its closest approach to the Sun. First spotted by Vladimir Bezugly in images from the SWAN instrument on the sun-staring SOHO spacecraft, the comet was surprisingly bright but understandably difficult to see against the Sun's glare. Still close to the Sun on the sky, the greenish coma and tail of C/2025 R2 (SWAN) are captured in this telescopic snapshot from September 17. Spica, alpha star...

Explanation: A newly discovered comet is already visible with binoculars. The comet, C/2025 R2 (SWAN) and nicknamed SWAN25B, is brightening significantly as it emerges from the Sun's direction and might soon become visible on your smartphone -- if not your eyes. Although the brightnesses of comets are notoriously hard to predict, many comets appear brighter as they approach the Earth, with SWAN25B reaching only a quarter of the Earth-Sun distance near October 19. Nighttime skygazers will also be watching for a SWAN25B-spawned meteor shower around October 5 when our Earth passes through the plane of the comet's orbit. The unexpectedly...

Explanation: It may look like these comets are racing, but they are not. Comets C/2025 K1 ATLAS (left) and C/2025 R2 SWAN (right) appeared near each other by chance last week in the featured image taken from France's Reunion Island in the southern Indian Ocean. Fainter Comet ATLAS is approaching our Sun and will reach its closest approach in early October when it is also expected to be its brightest -- although still only likely visible with long exposures on a camera. The brighter comet, nicknamed SWAN25B, is now headed away from our Sun, although its closest approach to Earth...

We’re gonna need a bigger telescope. Scientists have discovered that the 3I/ATLAS — a Manhattan-sized interstellar object that potentially has alien tech — is much larger than previously thought, according to a new report. First discovered by NASA on July 1, the cosmic anomaly has been under watch by Harvard astrophysicist Avi Loeb and his team as it shoots across the solar system. The object, which is believed to be a comet, reportedly has interstellar origins, making it the third ever object from beyond the solar system ever detected after ‘Oumuamua, which was discovered in 2017, and 2I/Borisov in 2019....

The mysterious comet 3I/ATLAS appears to be extremely large, making it orders of magnitude more massive than two other confirmed interstellar objects observed in our solar system in years past, a new study suggests. Based on a new analysis of the most precise tracking data collected on the object since its discovery in July, the interstellar comet appears to be “anomalously massive,” a finding that raises new questions regarding our expectations about interstellar objects that occasionally traverse our solar system. The research was detailed in a new paper by Richard Cloete, Peter Vere, and Harvard astronomer Avi Loeb, which places...

The IMAP mission will chart the boundary of the heliosphere, a bubble inflated by the solar wind that shields our solar system from galactic cosmic rays...NOAA's SWFO-L1 is designed to be a full-time operational space weather observatory...The Carruthers Geocorona Observatory is the first mission dedicated to recording changes in the outermost layer of our atmosphere, the exosphere...

Explanation: On the morning of September 24 a rocket crosses the bright solar disk in this long range telescopic snapshot captured from Orlando, Florida. That's about 50 miles north of its Kennedy Space Center launch site. This rocket carried three new space weather missions to space. Signals have now been successfully acquired from all three - NASA's Interstellar Mapping and Acceleration Probe, NASA’s Carruthers Geocorona Observatory, and the National Oceanic and Atmospheric Administration (NOAA) Space Weather Follow-On Lagrange 1 (SWFO-L1) - as they begin their journey to L1, an Earth-Sun lagrange point. L1 is about 1.5 million kilometers in the...

A New Asteroid Crater Was Just Discovered Under The Sea | 8:01 OzGeology | 149K subscribers | 106,346 views | September 24, 2025 00:00-00:36 - The Silverpit Impact Crater Is First Discovered 00:37-00:56 - The Silverpit Mystery 00:57-02:07 - The Silverpit Impact Structure 02:08-03:00 - The Geological Debate 03:01-03:57 - The Recent Data That Led To The Discovery 03:58-04:31 - What The Asteroid Collision Would've Looked Like 04:32-04:50 - The Mega Tsunami The Collision Generated 04:51-05:25 - Why The Silverpit Crater Has Survived Intact 05:26-06:11 - The Chance Discovery 06:12-06:43 - Life During The Eocene 06:44-07:16 - The Questions That...

Explanation: A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21. A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS), can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The...

A new study explains that time travel itself eventually leads to a reality without it. Is time travel truly possible? The prospect presents its fair share of paradoxes. Of course, there are famous logical examples, such as the Grandfather paradox, which explores what would happen if a time traveler killed their grandparent before their parent was conceived (an idea not so far removed from the plot of the sci-fi great Back to the Future). Other paradoxes are more concerned with mathematical or physical impossibilities within our current understanding of space-time—even though time travel is theoretically possible through phenomena like closed...

Earlier this year, astronomers watched a burst of high-energy light that kept roaring back for nearly a full day. Gamma-ray bursts (GRBs) are usually sorted into short and long events, and they generally last from milliseconds to a few minutes. In a new study, researchers describe a signal named GRB 250702B that fired three distinct times over a few hours, with soft X-rays flaring even earlier. The team also reported evidence that the source lies beyond our galaxy. Lead researchers Antonio Martin-Carrillo of University College Dublin (UCD) and Andrew J. Levan of Radboud University (RU) directed the effort. Their teams...

Ever wondered how life began and whether there is life on other planets? You're not alone, but the curiosity rarely turns into a career. The UW astrobiology program gives hope to would-be professional stargazers. Astrobiology -- the study of life in the universe -- looks for scientific answers to questions like "How did life begin on this planet?" and "Are we alone in the universe?" The field builds on knowledge across several disciplines. UW biology professor Peter Ward and UW astronomy professor Donald Brownlee believe discovering intelligent aliens on other planets is unlikely. In Rare Earth, a book the two...

Are We Alone?Our recent success on Mars leaves us no reason to think otherwise--and reason to ponder what makes the earth unique. By: Jay W. Richards & Guillermo Gonzalez The American Spectator May 1, 2004 The American taxpayers recently footed the bill for a risky $800 million NASA mission. The good news? It worked. In January, two NASA landers bounced to their destinations and released their rovers Spirit and Opportunity to prowl the Martian landscape. These remarkable little robots were not searching for archaeological ruins or strange, black monoliths but something much less exotic--the fingerprints of water in liquid form....

http://www.spacedaily.com/news/life-02a.html A Universe Of Life: Maybe Not by Karl Hill Las Cruces - Jan 7, 2002 This vast universe surely holds plenty of worlds where life can flourish, right? Don't bet on it, says New Mexico State University physicist Slava Solomatov. The more scientists learn about the conditions that make life possible on Earth, the more they realize how complex those factors are -- and how a relatively small change in one condition or another could have rendered the planet uninhabitable, Solomatov said. "It's a very finely tuned system," he said. "Some of the factors are well known, but we ...

In 1993, French astronomer Jacques Laskar ran a series of calculations indicating that the gravity of the Moon is vital to stabilizing the tilt of our planet. Earth's obliquity, as this tilt is technically known as, has huge repercussions for climate. Laskar argued that should Earth's obliquity wander over hundreds of thousands of years, it would cause environmental chaos by creating a climate too variable for complex life to develop in relative peace. So his argument goes, we should feel remarkably lucky to have such a large moon on our doorstep, as no other terrestrial planet in our solar system...

If you ever find yourself at a cocktail party of astrophysicists and don't know what to say, try this: "But what about the angular momentum?" No matter what the topic of conversation, you'll be guaranteed to sound erudite. Nearly every field of astronomy, from galaxy formation to star formation, has an "angular momentum problem." Nothing in the cosmos ever seems to spin or orbit at the rate it should. The moon is no exception. It is the flywheel to end all flywheels; if its orbital angular momentum were transferred to Earth's axial rotation, our planet would come close to spinning ...

Without the Moon, there would have been no life on Earth. Four billion years ago, when life began, the Moon orbited much closer to us than it does now, causing massive tides to ebb and flow every few hours. These tides caused dramatic fluctuations in salinity around coastlines which could have driven the evolution of early DNA-like biomolecules. This hypothesis, which is the work of Richard Lathe, a molecular biologist at Pieta Research in Edinburgh, UK, also suggests that life could not have begun on Mars. According to one theory for the origin of life, self-replicating molecules such as DNA...

The moon formed after a nasty planetary collision with young Earth, yet it looks odd next to its watery orbital neighbor. Turns out it really is odd: Only about one in every 10 to 20 solar systems may harbor a similar moon. New observations made by NASA's Spitzer Space Telescope of stellar dust clouds suggest that moons like Earth's are—at most—in only 5 to 10 percent of planetary systems. "When a moon forms from a violent collision, dust should be blasted everywhere," said Nadya Gorlova, an astronomer at the University of Florida in Gainesville who analyzed the telescope data in...

Moons like the Earth's - which are formed in catastrophic collisions - are extremely rare in the Universe, a study by US astronomers suggests. The Moon was created when an object as big as the planet Mars smacked into the Earth billions of years ago. The impact hurled debris into orbit, some of which eventually consolidated to form our Moon. The Astrophysical Journal reports that just 5-10% of planetary systems in the Universe have moons created this way.