https://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. The Gaia mission has allowed researchers to understand the motions of stars like never before, even revealing possible interactions between our solar system and nearby stars. Planetary Science Institute Senior Scientist Nathan Kaib and collaborator Sean Raymond (Universite de Bordeaux) have found that a recent stellar passage likely triggered a huge increase in comet formation as the star's gravity altered Oort cloud objects' orbits, sending them cascading into the inner solar system. We may even still be feeling the effects of this passage today. This work is being presented at the American Astronomical Society Division on Dynamical Astronomy. https://phys.org/news/2026-06-ancient-stellar-flyby-period-comets.html Astronomy Thu, 25 Jun 2026 19:40:04 EDT news701625061 Astronomers have long sought evidence to explain why comets at the outskirts of our own solar system contain crystalline silicates, since crystals require intense heat to form and these "dirty snowballs" spend most of their time in the ultracold Kuiper Belt and Oort Cloud. Now, looking outside our solar system, NASA's James Webb Space Telescope has returned the first conclusive evidence that links how those conditions are possible. https://phys.org/news/2026-01-webb-young-sun-star-forging.html Astronomy Wed, 21 Jan 2026 14:55:41 EST news688229701 Two bright green comets are streaming through the skies and are visible to skygazers in the Northern Hemisphere. https://phys.org/news/2025-10-green-comets-bright-night-sky.html Space Exploration Thu, 16 Oct 2025 12:41:41 EDT news679837287 A team of astronomers has made a groundbreaking discovery by detecting molecular activity in comet C/2014 UN271 (Bernardinelli-Bernstein)—the largest and second most distantly active comet ever observed from the Oort Cloud. https://phys.org/news/2025-06-largest-oort-cloud-comet-reveals.html Astronomy Tue, 17 Jun 2025 11:13:03 EDT news669377581 Scientists have unlocked one of the solar system's many secrets from an unexpected source: a planetarium show opening to the public on Monday. https://phys.org/news/2025-06-planetarium-scientists-cosmic-secret.html Astronomy Tue, 03 Jun 2025 11:05:34 EDT news668167529 It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. https://phys.org/news/2025-05-mysterious-planet.html Planetary Sciences Thu, 29 May 2025 05:01:31 EDT news667713684 A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study's School of Natural Sciences, has discovered an extraordinary trans-Neptunian object (TNO), named 2017 OF201, at the edge of our solar system. https://phys.org/news/2025-05-extreme-cousin-pluto-dwarf-planet.html Astronomy Thu, 22 May 2025 10:37:10 EDT news667129026 Interstellar material has been discovered in our solar system, but researchers continue to hunt for where it came from and how it got here. A new study led by Western astrophysicists Cole Gregg and Paul Wiegert recommends Alpha Centauri—the next closest solar system to ours—is a great place to start, highlighting how and why it's a prime target. https://phys.org/news/2025-03-astrophysicists-unexpected-space-solar-alpha.html Planetary Sciences Thu, 06 Mar 2025 13:10:30 EST news660489024 New studies led by researchers at the University of Central Florida offer for the first time a clearer picture of how the outer solar system formed and evolved based on analyses of trans-Neptunian objects (TNOs) and centaurs. https://phys.org/news/2024-12-webb-glimpse-icy-planetesimals-early.html Astronomy Thu, 19 Dec 2024 10:22:30 EST news653826143 Trying to understand the makeup and evolution of the solar system's Kuiper belt has kept researchers busy since it was hypothesized soon after the discovery of Pluto in 1930. In particular, binary pairs of objects there are useful as indicators since their existence today paints a picture of how energetic or violent the evolution of the solar system was in its early days four billion years ago. https://phys.org/news/2024-11-ultrawide-binary-kuiper-belt-earliest.html Astronomy Tue, 26 Nov 2024 07:25:11 EST news651756713 Identifying asteroids on a potential collision course with Earth could be made easier thanks to an advancement in how to track their orbits more precisely. https://phys.org/news/2024-11-earth-bound-asteroids-tracked-precisely.html Planetary Sciences Mon, 25 Nov 2024 12:05:15 EST news651758709 Prepare to spot a rare, bright comet. The space rock is slinging toward Earth from the outer reaches of the solar system and will make its closest pass on Saturday. It should be visible through the end of October, clear skies permitting. https://phys.org/news/2024-10-tsuchinshan-atlas-comet-visible-naked.html Space Exploration Wed, 09 Oct 2024 12:20:46 EDT news647695236 Stargazers will have the chance to spot what could be the most impressive comet of the year over the coming weeks. https://phys.org/news/2024-09-comet-a3-tsuchinshan-atlas.html Astronomy Mon, 30 Sep 2024 09:15:07 EDT news646906500 A comet is expected to risk having its tail clipped on Friday by flying perilously close to the sun, promising fireworks next month should it survive the fraught flypast. https://phys.org/news/2024-09-fireworks-comet-survives-risky-sun.html Space Exploration Sat, 28 Sep 2024 05:28:05 EDT news646720065 An international team of 45 researchers studying meteor showers has found that not all comets crumble the same way when they approach the sun. In a paper published in the journal Icarus, they ascribe the differences to the conditions in the protoplanetary disk where comets formed 4.5 billion years ago. https://phys.org/news/2024-08-meteor-showers-comets-early-solar.html Planetary Sciences Thu, 22 Aug 2024 12:51:03 EDT news643549861 A multi-institutional team of planetary scientists has learned more about the early composition of the solar system by studying a meteorite named Northwest Africa 14250. In their study, published in the journal Science Advances, the group used a scanning tunneling microscope to learn more about the isotopic makeup of clasts inside the sample. https://phys.org/news/2024-06-meteorite-northwest-africa-reveals-composition.html Planetary Sciences Mon, 17 Jun 2024 10:30:01 EDT news637838534 A trio of astronomers from Armagh Observatory & Planetarium and Centro de Astrobiología (CAB), CSIC-INTA has found that a white dwarf that was recently projected to make its way toward our solar system will not do so. https://phys.org/news/2023-06-white-dwarf-strong-magnetic-field.html Astronomy Fri, 23 Jun 2023 11:20:01 EDT news606733504 In 2017, a mysterious comet dubbed 'Oumuamua fired the imaginations of scientists and the public alike. It was the first known visitor from outside our solar system, it had no bright coma or dust tail, like most comets, and a peculiar shape—something between a cigar and a pancake—and its small size more befitted an asteroid than a comet. https://phys.org/news/2023-03-simple-explanation-oumuamua-weird-orbit.html Astronomy Wed, 22 Mar 2023 12:00:04 EDT news598704688 Today Venus has a dry, oxygen-poor atmosphere. But recent studies have proposed that the early planet may have had liquid water and reflective clouds that could have sustained habitable conditions. Researchers at the University of Chicago, Department of Geophysical Sciences, have built a new time-dependent model of Venus's atmospheric composition to explore these claims. Their findings have been published in the Proceedings of the National Academy of Sciences. https://phys.org/news/2023-03-venus-oceans-life-earth.html Planetary Sciences Fri, 10 Mar 2023 09:50:01 EST news597662173 With simulations that go into finer details than ever before, Brooke Polak of the University of Heidelberg and Hubert Klahr at the Max Planck Institute for Astronomy (MPIA) have modeled a key phase in the formation of planets in our solar system: the way that centimeter-size pebbles aggregate into so-called planetesimals tens to hundreds kilometers in size. The simulation reproduces the initial size distribution of planetesimals, which can be checked against observations of present-day asteroids. It also predicts the prevalence of close binary planetesimals in our solar system. https://phys.org/news/2023-02-numerical-simulations-planetesimal-formation-key.html Astronomy Wed, 01 Feb 2023 12:42:53 EST news594477765 A newly discovered comet could be visible to the naked eye as it shoots past Earth and the Sun in the coming weeks for the first time in 50,000 years, astronomers have said. https://phys.org/news/2023-01-year-comet-visible-naked-eye.html Space Exploration Sat, 07 Jan 2023 05:55:38 EST news592293332 Researchers from Western have shown that a fireball that originated at the edge of the solar system was likely made of rock, not ice, challenging long-held beliefs about how the solar system was formed. https://phys.org/news/2022-12-unexpected-space-defies-theories-solar.html Astronomy Mon, 12 Dec 2022 12:58:59 EST news590072336 A new study from the University of Central Florida has found strong support that the outgassing of molecules from comets could be the result of the composition from the beginning of our solar system. https://phys.org/news/2022-11-comets-insight-chemical-composition-early.html Planetary Sciences Fri, 04 Nov 2022 16:42:23 EDT news586798938 "To see a world in a grain of sand," the opening sentence of the poem by William Blake, is an oft-used phrase that also captures some of what geologists do. https://phys.org/news/2022-08-scientists-earth-path-galaxy-tiny.html Planetary Sciences Wed, 24 Aug 2022 08:58:04 EDT news580550276 Dr. Lu Xing, an associate researcher from the Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences, along with collaborators from Yunnan University, the Harvard-Smithsonian Center for Astrophysics, and the Max Planck Institute, have used high-resolution observational data from the Atacama Large Millimeter/submillimeter Array (ALMA) to discover a massive protostellar disk in the Galactic Center and determine how its spiral arms were formed. https://phys.org/news/2022-06-encounter-years-spirals-accretion-disk.html Astronomy Thu, 02 Jun 2022 12:57:53 EDT news573393470 New chemistry "forensics" indicate that the stone named Hypatia from the Egyptian desert could be the first tangible evidence found on Earth of a supernova type Ia explosion. These rare supernovas are some of the most energetic events in the universe. https://phys.org/news/2022-05-extraterrestrial-stone-supernova-clues-earth.html Astronomy Mon, 16 May 2022 10:48:06 EDT news571916878 An enormous comet—approximately 80 miles across, more than twice the width of Rhode Island—is heading our way at 22,000 miles per hour from the edge of the solar system. Fortunately, it will never get closer than 1 billion miles from the sun, which is slightly farther from Earth than Saturn; that will be in 2031. https://phys.org/news/2022-04-billion-year-old-relic-early-solar.html Astronomy Tue, 12 Apr 2022 10:46:55 EDT news568979207 The solar system has eight planets. In 2006, astronomers reclassified Pluto as a dwarf planet, the same class that contains Eris, Sedna, Quaoar, Ceres and perhaps many more solar system small bodies. These are defined approximately as bodies that orbit the sun but that are not massive enough (unlike regular planets) to gravitationally dominate their environments by clearing away material. Astronomers wonder, though, whether there might not really be a ninth planet previously undiscovered but lurking in the outer reaches of the solar system, perhaps in the giant Oort cloud of objects that begins hundreds of astronomical units (au) from the sun and extends outward. https://phys.org/news/2022-03-planet.html Astronomy Mon, 14 Mar 2022 12:50:02 EDT news566477137 Pictures of the Milky Way show billions of stars arranged in a spiral pattern radiating out from the center, with illuminated gas in between. But our eyes can only glimpse the surface of what holds our galaxy together. About 95 percent of the mass of our galaxy is invisible and does not interact with light. It is made of a mysterious substance called dark matter, which has never been directly measured. https://phys.org/news/2022-02-dark-solar.html Astronomy Tue, 08 Feb 2022 11:00:09 EST news563540405 A team of researchers with the Paris observatory and Instituto de Astrofísica de Andalucía-CSIC, has confirmed that comet 2014 UN271 is the largest comet ever observed. They published a paper describing their findings on the arXiv preprint server, and it has been accepted for publication in Astronomy and Astrophysics Letters. https://phys.org/news/2022-02-comet-un271-largest.html Astronomy Tue, 08 Feb 2022 09:00:01 EST news563532573