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 two largest planets in our solar system, Jupiter and Saturn, also have the largest satellite systems, or the most moons. At present, Jupiter's reported moon count stands at more than 100 moons, and along with its many rings, Saturn has more than 280 reported moons. Not all these moons are equal, however. Jupiter's moon family has four large members, including the largest moon in the solar system, Ganymede, while Saturn's family is dominated by one large moon, Titan, the solar system's second largest. https://phys.org/news/2026-04-jupiter-cultivated-large-moons-saturn.html Astronomy Tue, 07 Apr 2026 11:20:04 EDT news694772744 Provided they host thick, hydrogen-dominated atmospheres, moons orbiting free-floating exoplanets could retain much of the heat generated deep within their interiors by tidal forces. Led by David Dahlbüdding at the Max Planck Institute for Extraterrestrial Physics and Giulia Roccetti at the European Space Agency, a new study predicts that hydrogen could act as a potent greenhouse gas—potentially providing habitable conditions for billions of years after their host planets are first ejected from their stellar systems. The work has been published in Monthly Notices of the Royal Astronomical Society. https://phys.org/news/2026-03-moons-orbiting-exoplanets-habitable.html Astrobiology Sat, 21 Mar 2026 09:50:01 EDT news692440075 Liquid water is considered essential for life. Surprisingly, however, stable conditions that are conducive to life could exist far from any sun. A research team from the Excellence Cluster ORIGINS at LMU and the Max Planck Institute for Extraterrestrial Physics (MPE) has shown that moons around free-floating planets can keep their water oceans liquid for up to 4.3 billion years by virtue of dense hydrogen atmospheres and tidal heating—that is to say, for almost as long as Earth has existed and sufficient time for complex life to develop. https://phys.org/news/2026-03-hydrogen-atmosphere-exomoons-habitable-billions.html Astrobiology Wed, 11 Mar 2026 09:00:07 EDT news692437555 Using NASA's Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has discovered a new exoplanet orbiting a distant star known as TIC-65910228. The newfound alien world is slightly larger and nearly five times more massive than Jupiter. The discovery was reported in a paper published Feb. 13 on the arXiv pre-print server. https://phys.org/news/2026-02-astronomers-rare-super-jupiter-orbiting.html Astronomy Mon, 23 Feb 2026 11:40:01 EST news691060585 Astronomers may have discovered a scrawny star bolting through the middle of our galaxy with a planet in tow. If confirmed, the pair sets a new record for the fastest-moving exoplanet system, nearly double our solar system's speed through the Milky Way. https://phys.org/news/2025-02-scientists-candidate-speediest-exoplanet.html Planetary Sciences Mon, 10 Feb 2025 11:19:07 EST news658408741 New research done at NASA's Jet Propulsion Laboratory reveals potential signs of a rocky, volcanic moon orbiting an exoplanet 635 light-years from Earth. The biggest clue is a sodium cloud that the findings suggest is close to but slightly out of sync with the exoplanet, a Saturn-size gas giant named WASP-49 b, although additional research is needed to confirm the cloud's behavior. Within our solar system, gas emissions from Jupiter's volcanic moon Io create a similar phenomenon. https://phys.org/news/2024-10-distant-planet-host-volcanic-moon.html Planetary Sciences Thu, 10 Oct 2024 13:56:04 EDT news647787361 Scientists around the world are constantly on the hunt for planets outside our solar system that could potentially provide a habitable environment for life. https://phys.org/news/2024-06-earth-small-planets.html Planetary Sciences Tue, 18 Jun 2024 12:17:05 EDT news637931822 A team of astronomers and citizen scientists has discovered a planet in the habitable zone of an unusual star system, including two stars and potentially another exoplanet. https://phys.org/news/2024-04-citizen-scientists-exoplanet-binary-star.html Astronomy Tue, 30 Apr 2024 12:15:38 EDT news633698133 Only two of the more than 5,300 known exoplanets have so far provided evidence of moons in orbit around them. In observations of the planets Kepler-1625b and Kepler-1708b from the Kepler and Hubble space telescopes, researchers discovered traces of such moons for the first time. https://phys.org/news/2023-12-large-exomoons-kepler-astronomers.html Astronomy Thu, 07 Dec 2023 11:17:04 EST news621170221 The SETI Institute and its partner Unistellar are launching a new exoplanet detection program that will engage citizen scientists worldwide. Amateur astronomers, using either Unistellar's eVscope or another telescope, will be invited to help confirm exoplanet candidates identified by NASA's Transiting Exoplanet Survey Satellite (TESS) by observing possible exoplanet transits from Earth. https://phys.org/news/2022-09-exoplanet-citizen-scientists.html Astronomy Mon, 19 Sep 2022 12:51:30 EDT news582810686 Our solar system contains eight planets and more than 200 moons. The large majority of those moons have no chance of being habitable, but some of them—Europa and Enceladus, for example—are strong candidates in the search for life. https://phys.org/news/2022-05-habitable-exomoons.html Astronomy Thu, 12 May 2022 10:26:33 EDT news571569989 Earth's moon is vitally important in making Earth the planet we know today: The moon controls the length of the day and ocean tides, which affect the biological cycles of lifeforms on our planet. The moon also contributes to Earth's climate by stabilizing Earth's spin axis, offering an ideal environment for life to develop and evolve. https://phys.org/news/2022-02-moons-yield-clues-planets-habitable.html Planetary Sciences Tue, 01 Feb 2022 16:03:48 EST news562953825 Astronomers have reported a second, super-sized moon orbiting a Jupiter-sized planet beyond our solar system. If confirmed, the sighting could mean that exomoons are as common in the universe as exoplanets, and that big or small, such moons are a feature of planetary systems. But it could be a long wait. The first-ever sighting of an exomoon four years ago is still awaiting confirmation, and verification of this newest candidate could be as equally long and contentious. https://phys.org/news/2022-01-astronomers-evidence-supermoon-solar.html Astronomy Thu, 13 Jan 2022 11:00:06 EST news561282473 Finding an exact copy of the Earth somewhere in the universe sounds like a far-fetched notion, but scientists believe that because Earth happened in our solar system, something similar is bound to exist someplace else. University of Illinois Urbana-Champaign researcher Siegfried Eggl and his colleagues say orbiting moons may play a key role in keeping planets habitable over long periods and identified a method to find them. https://phys.org/news/2021-09-earthlike-planets-solar-moons.html Astronomy Thu, 09 Sep 2021 10:04:54 EDT news550400691 The moons of planets that have no parent star can possess an atmosphere and retain liquid water. Astrophysicists at LMU have calculated that such systems could harbor sufficient water to make life possible—and sustain it. https://phys.org/news/2021-06-liquid-exomoons-free-floating-planets.html Astronomy Thu, 10 Jun 2021 11:17:11 EDT news542542629 So far, the search for extraterrestrial life has focused on planets at a distance from their star where liquid water is possible on the surface. But within our Solar System, most of the liquid water seems to be outside this zone. Moons around cold gas giants are heated beyond the melting point by tidal forces. The search area in other planetary systems therefore increases if we also consider moons. Researchers from SRON and RUG have now found a formula to calculate the presence and depth of subsurface oceans in these 'exomoons." https://phys.org/news/2020-04-astronomers-formula-subsurface-oceans-exomoons.html Astronomy Thu, 23 Apr 2020 10:47:00 EDT news506857617 Numerical simulations show that the temperature gradient in the gas disk around a young gas giant planet could play a critical role in the development of a satellite system dominated by a single large moon, similar to Titan in the Saturn system. Researchers found that dust in the circumplanetary disk can create a "safety zone" that keeps the moon from falling into the planet as the system evolves. https://phys.org/news/2020-03-safety-zone-giant-moons-fatal.html Astronomy Mon, 09 Mar 2020 08:37:57 EDT news502961874 What is the difference between a planet-satellite system as we have with the Earth and moon, versus a binary planet—two planets orbiting each other in a cosmic do-si-do? https://phys.org/news/2019-10-moons-stellar-reveal-planets-neptune.html Astronomy Thu, 03 Oct 2019 09:09:48 EDT news489312580 For years, astronomers have looked up at the sky and speculated about the strange dimming behavior of Tabby's Star. https://phys.org/news/2019-09-dimming-tabby-star.html Astronomy Mon, 16 Sep 2019 11:31:28 EDT news487852280 In The Little Prince, the classic novella by Antoine de Saint-Exupéry, the titular prince lives on a house-sized asteroid so small that he can watch the sunset any time of day by moving his chair a few steps. https://phys.org/news/2019-09-redefines-limit-planet-size-habitability.html Astronomy Wed, 11 Sep 2019 08:20:19 EDT news487408811 A rocky extrasolar moon (exomoon) with bubbling lava may orbit a planet 550 light-years away from us. This is suggested by an international team of researchers led by the University of Bern on the basis of theoretical predictions matching observations. The "exo-Io" would appear to be an extreme version of Jupiter's moon Io. https://phys.org/news/2019-08-hints-volcanically-exomoon.html Astronomy Thu, 29 Aug 2019 11:32:39 EDT news486297148 Moons ejected from orbits around gas giant exoplanets could explain several astronomical mysteries, an international team of astronomers suggests. https://phys.org/news/2019-07-ploonets-exiled-moons-astronomical-mysteries.html Astronomy Fri, 12 Jul 2019 07:32:43 EDT news482135554 Moons orbiting planets outside our solar system could offer another clue about the pool of worlds that may be home to extra-terrestrial life, according to an astrophysicist at the University of Lincoln. https://phys.org/news/2019-06-exomoons-home-extra-terrestrial-life.html Astronomy Tue, 04 Jun 2019 12:32:59 EDT news478870368 Two teams working independently have looked at the possibility of an exomoon circling the exoplanet Kepler-1625b, which orbits the star Kepler-1625. They report little to no evidence supporting its existence. One team, led by Laura Kreidberg, has written a paper describing their work, which is posted on the arXiv preprint server. Another team led by René Heller published a paper in the journal Astronomy Astrophysics. The team that announced possible evidence of the exomoon last year, led by Alex Teachey, has written another paper in response to the findings by the new researchers that is available on arXiv. https://phys.org/news/2019-05-exomoon.html Astronomy Mon, 06 May 2019 10:30:04 EDT news476357395 "Can moons have moons?" https://phys.org/news/2019-01-earth-submoon.html Space Exploration Wed, 23 Jan 2019 15:24:30 EST news467479462 Astrophysicists of the University of Zürich, ETH Zürich and the NCCR PlanetS show how the icy moons of Uranus were born. Their result suggests that such potentially habitable worlds are much more abundant in the Universe than previously thought. The unprecedentedly complex computer simulations were performed at the Swiss National Supercomputing Centre (CSCS) in Lugano. https://phys.org/news/2018-11-prospects-moon-hunters.html Astronomy Tue, 20 Nov 2018 07:37:16 EST news461921830 A pair of Columbia University astronomers using NASA's Hubble Space Telescope and Kepler Space Telescope have assembled compelling evidence for the existence of a moon orbiting a gas-giant planet 8,000 light-years away. https://phys.org/news/2018-10-astronomers-compelling-evidence-moon-solar.html Astronomy Wed, 03 Oct 2018 14:00:11 EDT news457776650 We've all heard about the search for life on other planets, but what about looking on other moons? https://phys.org/news/2018-06-giant-planets-habitable-moons.html Astronomy Thu, 14 Jun 2018 15:28:34 EDT news448208765 We've all heard about the search for life on other planets, but what about looking on other moons? https://phys.org/news/2018-05-giant-planets-habitable-moons.html Astronomy Thu, 31 May 2018 04:56:57 EDT news446961400 René Heller, a space scientist with the Maxx Planck Institute for Solar System Research has uploaded a paper to the arXiv preprint server offering possible attributes for the still-unconfirmed exomoon Kepler 1625 b-i. He suggests that if the exomoon does truly exist, it is probably unlike any of the moons in our solar system, which suggests that theories about the origins of moons might have to be expanded. https://phys.org/news/2017-10-unconfirmed-exomoon-solar.html Astronomy Wed, 25 Oct 2017 11:00:04 EDT news428139327