Latest news with #PlanetaryScienceJournal
Yahoo
12-03-2025
- Science
- Yahoo
128 New Moons Found Orbiting Saturn in Mindblowing Discovery
The race between Jupiter and Saturn for the most moons in the Solar System may have just finally come screeching to a halt. A team of scientists has found a whopping 128 previously unknown moons hanging around Saturn, in a discovery officially recognized by the International Astronomical Union. This brings the planet's total number of known moons to 274, leaving Jupiter, with its mere 95 moons, in the dust. The first hint that there were more moons awaiting discovery came between 2019 and 2021, when 62 such objects were identified. Other small objects were also spotted at the time that couldn't yet be designated. "With the knowledge that these were probably moons, and that there were likely even more waiting to be discovered, we revisited the same sky fields for three consecutive months in 2023," says astronomer Edward Ashton of Academia Sincia in Taiwan. "Sure enough, we found 128 new moons. Based on our projections, I don't think Jupiter will ever catch up." These moons, to be clear, are not like Earth's Moon, nice and large and pleasingly spherical. They are tiny moonlets, all blobby and potato-shaped, just a few kilometers across – what are known as irregular moons. The researchers believe that they originally comprised a small group of objects captured by gravity in Saturn's orbit early in the Solar System's history. A subsequent series of collisions would have smashed them to moony bits, resulting in the preponderance of small rocks the astronomers have found. In fact, they believe a collision must have taken place as recently as 100 million years ago, which is a very short eyeblink of time for a planet. The location of the moons, too, within the Norse group of Saturn's moons, suggests that this is the place where the recent collision occurred. The Norse group are moons that orbit in a retrograde direction, at inclined angles, and on elliptical paths, outside Saturn's rings. Like the newly discovered moons, they, too, are relatively potatoey. Potatoes. Rings. Sounds familiar, somehow… One haul of 64 moons has been detailed in a new paper submitted to the Planetary Science Journal. The preprint is available on arXiv. Space Force's Secret Plane Returns After More Than a Year in Orbit Study Traces Our Solar System's Journey Through a Massive Galactic Wave Our Moon Is About to Turn Blood Red. Here's Why.
Yahoo
19-02-2025
- Science
- Yahoo
Scientists Think Visitors From Another Star System May Have Infiltrated Our Galactic Neighborhood
Alpha Centauri is the star system closest to our Solar System, and it is likely that particles from it could be making their way over to or already be in our stellar neighborhood. To know what to expect, researchers used existing models to predict how many particles of different sizes may already exist in the Solar System and are possibly coming in from Alpha Centauri every year. Studying the ejection and transfer of particles from Alpha Centauri could tell us more about how material is exchanged between star systems. While interstellar objects ('Oumuamua, anyone?) have passed through our Solar System before, the origins of many of these objects remain unknown. Did they originate in a nearby star system? A distant one? A completely different galaxy? Unfortunately, it's not currently possible to track 'Oumuamua down for further study. Its highly eccentric orbit will take it too far for any spacecraft to reach or any telescope to observe. But that doesn't mean we have no interstellar subjects available for study—in fact, it turns out we have plenty of particles from another star system already here. The closest stellar system to us is the triple system Alpha Centauri. It's currently creeping closer to our Solar System at 79,000 km per hour (about 49,709 mph), and should be at its closest around 27,700 years from now. With that in mind, researchers Cole Gregg and Paul Wiegert from the University of Western Ontario decided to see how many Alpha Centauri objects might have made it to us already, and how many could eventually make it here in the future. 'A small number [less than 10 meteors] may currently be entering Earth's atmosphere every year,' Gregg and Wiegert said in a study soon to be published in the Planetary Science Journal, '[and] is expected to increase as Alpha Centauri approaches.' Alpha Centauri is a mature star system, at 5 billion years old. This means that most of the material in this system's protoplanetary disk has likely already dissipated, so it is not expected to release much debris out into space (though there might be material from the system in our asteroid belt and our distant Oort cloud). That said, the gravitational forces of more stars and planets make it more likely for material to scatter, and there may be planets orbiting its three stars (though, none have yet been confirmed). To find out if Alpha Centauri could be currently ejecting material, the researchers turned to existing models of how star systems usually eject debris. The models predicted that, despite the small number of objects from Alpha Centauri that are expected to make it all the way to Earth every year, there could be as many as a million over-one-hundred-meter-in-diameter-sized objects from the system already lurking in our Oort cloud (many smaller object and particles may also be among them). The problem is that the Oort cloud is on the outer edge of the Solar System. This would make potential Alpha Centauri objects—if they really are somewhere in there—difficult to observe. Though, it wouldn't be impossible. NASA's New Horizons Mission has a dust detector actively picking up on particles in the Kuiper belt that might have been leftovers from the formation of our Solar System. The Oort cloud is even further out, but despite a dwindling fuel supply, New Horizons may be able to hold on long enough to get out there and scan for the presence of something from Alpha Centauri. That said, the presence of these objects is not certain. There is also the issue of smaller particles from Alpha Centauri potentially not surviving the journey to the Solar System. They could be deflected by magnetic fields, slow down significantly due to drag in the interstellar medium, or end up decimated by extremely fast gas atoms or collisions with each other. For any particles that do survive and manage to enter the inner Solar System, the Sun's gravity will increase their velocity significantly. Even more particles could come from hypothetical comets—at least, they could if Alpha Centauri ejects as many as our Solar System—but these are unlikely to be observed. Whether these potential particles are actually detectable remains to be seen. 'A thorough understanding of the mechanisms by which material could be transferred from Alpha Centauri to the Solar System not only deepens our knowledge of interstellar transport,' the researchers said in the same study, 'but also opens new pathways for exploring the interconnectedness of stellar systems and the potential for material exchange across the galaxy.' You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
16-02-2025
- Science
- Yahoo
Alpha Centauri Sending Stream of Objects Into Our Solar System, Scientists Propose
The detection of a large interstellar object in 2017 named 'Oumuamua was a landmark discovery. Figuring out where the wayward traveler came from, though, is another challenge entirely, especially since it subsequently cruised back out of our star system. Nevertheless, that hasn't stopped intrepid astronomers from trying. In a case study published in the Planetary Science Journal and spotlighted by Universe Today, the researchers from The University of Western Ontario hypothesize a scenario in which our nearest stellar neighbor, Alpha Centauri, may be sending a steady stream of "interstellar material" our way. And tantalizingly, what they found suggests that our solar system may already be flooded with visitors from the star system, which is about 4.25 light years away. These objects range from microscopic in size to well over 100 yards in diameter — a far more significant presence than the background level of gas and dust diffused throughout the cosmos. However, the odds of encountering one of these objects within the heart our solar system remain exceedingly low, with only a one-in-a-million chance that an interstellar visitor is located within ten astronomical units, or just short of one billion miles, of the Sun, according to the scientists. Though it appears as a single bright speck in the sky, Alpha Centauri is actually a triple star system, with several suspected exoplanets, including a super-Earth called Proxima Centauri b, with more thought to be lurking in the shadows. Two of the stars are Sun-like ones locked in a binary dance, while another star, a dim red dwarf, acts as the proverbial third wheel. And with all those big personalities involved and clashing gravitational egos, it's likely that Alpha Centauri boots out a significant amount of material, some of which may have reached the Oort Cloud, a shell of icy objects that surrounds the solar system, the researchers said. Alpha Centauri is also moving towards us, and in some 28,000 years from now, it'll reach its closest point at a distance of a little over three light years away, raising the odds of an interstellar influx in the future, too. "Though mature star systems likely eject less material than those in their planet-forming years, the presence of multiple stars and planets increases the likelihood of gravitational scattering of members from any remnant planetesimal reservoirs, much as asteroids or comets are currently being ejected from our solar system," the researchers wrote in the study. In fact, the astronomers estimated there could be over 1,000,000 objects larger than 328 feet in diameter from the nearby system lurking in the Oort Cloud. For reference, 'Oumuamua is believed to be anywhere between 328 to 3,280 feet long. That's a lot of refugees. It's unlikely we'll ever detect the vast majority of them, though. And when you consider the astronomers determined that particles as small as just ten microns, or about the size of a human blood cell, could survive the ten million-year journey over, it sounds like our corner of the universe may be awash with interstellar particles that even our most advanced instruments will have no chance of picking up on. A silver lining: the authors predict that around ten Alpha Centauri rejects could enter the Earth's atmosphere, where they'd be detectable as meteorites. With any luck, some of them could originate from one of the star system's exoplanets, providing a potential glimpse of worlds light years away. "A thorough understanding of the mechanisms by which material could be transferred from Alpha Centauri to the solar system not only deepens our knowledge of interstellar transport but also opens new pathways for exploring the interconnectedness of stellar systems and the potential for material exchange across the Galaxy," the paper reads. More on space: Don't Panic, But the Chances of That City Killer Asteroid Hitting Earth Just Almost Doubled
