Latest news with #solar system
CTV News
6 hours ago
- Science
- CTV News
Researchers may have solved mystery of Mercury's missing meteorites, but doubts remain
Researchers suspect that two meteorites found in the Sahara Desert in 2023 may originally have come from Mercury, which would make them the first identified fragments of the solar system's innermost planet. The least studied and most mysterious of the solar system's rocky planets, Mercury is so close to the sun that exploring it is difficult even for probes. Only two uncrewed spacecraft have visited it to date — Mariner 10, launched in 1973, and MESSENGER, launched in 2004. A third, BepiColombo, is en route and due to enter orbit around the planet in late 2026. Scientists know little about Mercury's geology and composition, and they have never been able to study a fragment of the planet that landed on Earth as a meteorite. In contrast, there are more than 1,100 known samples from the moon and Mars in the database of the Meteoritical Society, an organization that catalogs all known meteorites. These 1,100 meteorites originated as fragments flung from the surfaces of the moon and Mars during asteroid impacts before making their way to Earth after a journey through space. Not every planet is likely to eject fragments of itself Earth-ward during collisions. Though Venus is closer to us than Mars is, its greater gravitational pull and thick atmosphere may prevent the launch of impact debris. But some astronomers believe that Mercury should be capable of generating meteors. 'Based on the amount of lunar and Martian meteorites, we should have around 10 Mercury meteorites, according to dynamical modeling,' said Ben Rider-Stokes, a postdoctoral researcher in achondrite meteorites at the U.K.'s Open University and lead author of a study on the Sahara meteorites, published in June in the journal Icarus. 'However, Mercury is a lot closer to the sun, so anything that's ejected off Mercury also has to escape the sun's gravity to get to us. It is dynamically possible, just a lot harder. No one has confidently identified a meteorite from Mercury as of yet,' he said, adding that no mission thus far has been capable of bringing back physical samples from the planet either. If the two meteorites found in 2023 — named Northwest Africa 15915 (NWA 15915) and Ksar Ghilane 022 (KG 022) — were confirmed to be from Mercury, they would greatly advance scientists' understanding of the planet, according to Rider-Stokes. But he and his coauthors are the first to warn of some inconsistencies in matching those space rocks to what scientists know about Mercury. Mercury meteorite A fragment of Northwest Africa 15915, a meteorite found in 2023 that the study authors also believe could have originated from Mercury. Jared Collins via CNN Newsource The biggest is that the fragments appear to have formed about 500 million years earlier than the surface of Mercury itself. However, according to Rider-Stokes, this finding could be based on inaccurate estimates, making a conclusive assessment unlikely. 'Until we return material from Mercury or visit the surface,' he said, 'it will be very difficult to confidently prove, and disprove, a Mercurian origin for these samples.' But there are some compositional clues that suggest the meteorites might have a link to the planet closest to the sun. Hints of Mercurian origins It's not the first time that known meteorites have been associated with Mercury. The previous best candidate, based on the level of interest it piqued in astronomers, was a fragment called Northwest Africa (NWA) 7325, which was reportedly found in southern Morocco in early 2012. Rider-Stokes said that was the first meteorite to be potentially associated with Mercury: 'It got a lot of attention. A lot of people got very excited about it.' Further analysis, however, showed a richness in chrome at odds with Mercury's predicted surface composition. More recently, astronomers have suggested that a class of meteorites called aubrites — from a small meteorite that landed in 1836 in Aubres, France — might come from Mercury's mantle, the layer below the surface. However, these meteorites lack a chemical compatibility with what astronomers know about the planet's surface, Rider-Stokes said. 'That's what's so exciting about the samples that we studied — they have sort of the perfect chemistry to be representative of Mercury,' he said. Most of what is known about Mercury's surface and composition comes from NASA's MESSENGER probe, which assessed the makeup of the planet's crust from orbit. Both meteorites from the study, which Rider-Stokes analyzed with several instruments including an electron microscope, contain olivine and pyroxene, two iron-poor minerals confirmed by MESSENGER to be present on Mercury. The new analysis also revealed a complete lack of iron in the space rock samples, which is consistent with scientists' assumptions about the planet's surface. However, the meteorites contained only trace amounts of plagioclase, a mineral believed to dominate Mercury's surface. The biggest point of uncertainty, though, is still the meteorites' age. 'They are about 4.5 billion years old,' Rider-Stokes said, 'and most of Mercury's surface is only about 4 billion years old, so there's a 500 million-year difference.' However, he said he thinks this discrepancy is not sufficient to rule out a Mercurian origin, due to the limited reliability of MESSENGER's data, which has been also used to estimate the age of Mercury's surface layer. 'These estimates are based on impact cratering models and not absolute age dating, and therefore may not be entirely accurate,' Rider-Stokes said. 'It doesn't mean that these samples aren't good analogs for regional areas on the surface of Mercury, or the early Mercurian crust that is not visible on the modern surface of Mercury.' With more modern instruments now available, BepiColombo, the European Space Agency probe that will start studying Mercury in early 2027, may be able to answer long-standing questions about the planet, such as where it formed and whether it has any water. Mercury meteorite An image of a fragment of Ksar Ghilane 022, a meteorite found in the Sahara Desert in 2023 which authors of a new study suspect might have come from the planet Mercury. Jared Collins via CNN Newsource Having material confirmed to have come from other planetary bodies helps astronomers understand the nature of early solar system's building blocks, Rider-Stokes said, and identifying fragments of Mercury would be especially crucial since a mission to gather samples from the planet closest to the sun and bring them back would be extremely challenging and expensive. Clues to planet formation Sean Solomon, principal investigator for NASA's MESSENGER mission to Mercury, said in an email that he believes the two meteorites described in the recent paper likely did not originate from Mercury. Solomon, an adjunct senior research scientist at Columbia University in New York City, was not involved with the study. The primary reason Solomon cited for his doubts is that the meteorites formed much earlier than the best estimates for the ages of rocks now on Mercury's surface. But he said he thinks the samples still hold research value. 'Nonetheless, the two meteorites share many geochemical characteristics with Mercury surface materials, including little to no iron … and the presence of sulfur-rich minerals,' he added. 'These chemical traits have been interpreted to indicate that Mercury formed from precursor materials much more chemically reduced than those that formed Earth and the other inner planets. It may be that remnants of Mercury precursor materials still remain among meteorite parent bodies somewhere in the inner solar system, so the possibility that these two meteorites sample such materials warrants additional study.' Solomon also noted that it was difficult to persuade the planetary science community that there were samples from Mars in meteorite collections, and that it took precise matching of their chemistry with data about the surface of Mars taken by the Viking probes to convince researchers to take a closer look. Lunar meteorites were also not broadly acknowledged to be in meteorite collections until after the existence of Martian meteorites had been demonstrated in the 1980s, he added, even though the Apollo and Luna missions had returned abundant samples of lunar materials more than a decade earlier. Once samples are confirmed to be from a planetary body, Solomon said, they can provide crucial information not available from remote sensing by an orbiting spacecraft on the timing of key geological processes, the history of internal melting of the body, and clues to planet formation and early solar system processes. Rider-Stokes plans to continue the discussion around these meteorites at the annual meeting of the Meteoritical Society, which takes place in Perth this week. 'I'm going to discuss my findings with other academics across the world,' he said. 'At the moment, we can't definitively prove that these aren't from Mercury, so until that can be done, I think these samples will remain a major topic of debate across the planetary science community.'
CNN
9 hours ago
- Science
- CNN
Researchers may have solved mystery of Mercury's missing meteorites, but doubts remain
Researchers suspect that two meteorites found in the Sahara Desert in 2023 may originally have come from Mercury, which would make them the first identified fragments of the solar system's innermost planet. The least studied and most mysterious of the solar system's rocky planets, Mercury is so close to the sun that exploring it is difficult even for probes. Only two uncrewed spacecraft have visited it to date — Mariner 10, launched in 1973, and MESSENGER, launched in 2004. A third, BepiColombo, is en route and due to enter orbit around the planet in late 2026. Scientists know little about Mercury's geology and composition, and they have never been able to study a fragment of the planet that landed on Earth as a meteorite. In contrast, there are more than 1,100 known samples from the moon and Mars in the database of the Meteoritical Society, an organization that catalogs all known meteorites. These 1,100 meteorites originated as fragments flung from the surfaces of the moon and Mars during asteroid impacts before making their way to Earth after a journey through space. Not every planet is likely to eject fragments of itself Earth-ward during collisions. Though Venus is closer to us than Mars is, its greater gravitational pull and thick atmosphere may prevent the launch of impact debris. But some astronomers believe that Mercury should be capable of generating meteors. 'Based on the amount of lunar and Martian meteorites, we should have around 10 Mercury meteorites, according to dynamical modeling,' said Ben Rider-Stokes, a postdoctoral researcher in achondrite meteorites at the UK's Open University and lead author of a study on the Sahara meteorites, published in June in the journal Icarus. 'However, Mercury is a lot closer to the sun, so anything that's ejected off Mercury also has to escape the sun's gravity to get to us. It is dynamically possible, just a lot harder. No one has confidently identified a meteorite from Mercury as of yet,' he said, adding that no mission thus far has been capable of bringing back physical samples from the planet either. If the two meteorites found in 2023 — named Northwest Africa 15915 (NWA 15915) and Ksar Ghilane 022 (KG 022) — were confirmed to be from Mercury, they would greatly advance scientists' understanding of the planet, according to Rider-Stokes. But he and his coauthors are the first to warn of some inconsistencies in matching those space rocks to what scientists know about Mercury. The biggest is that the fragments appear to have formed about 500 million years earlier than the surface of Mercury itself. However, according to Rider-Stokes, this finding could be based on inaccurate estimates, making a conclusive assessment unlikely. 'Until we return material from Mercury or visit the surface,' he said, 'it will be very difficult to confidently prove, and disprove, a Mercurian origin for these samples.' But there are some compositional clues that suggest the meteorites might have a link to the planet closest to the sun. It's not the first time that known meteorites have been associated with Mercury. The previous best candidate, based on the level of interest it piqued in astronomers, was a fragment called Northwest Africa (NWA) 7325, which was reportedly found in southern Morocco in early 2012. Rider-Stokes said that was the first meteorite to be potentially associated with Mercury: 'It got a lot of attention. A lot of people got very excited about it.' Further analysis, however, showed a richness in chrome at odds with Mercury's predicted surface composition. More recently, astronomers have suggested that a class of meteorites called aubrites — from a small meteorite that landed in 1836 in Aubres, France — might come from Mercury's mantle, the layer below the surface. However, these meteorites lack a chemical compatibility with what astronomers know about the planet's surface, Rider-Stokes said. 'That's what's so exciting about the samples that we studied — they have sort of the perfect chemistry to be representative of Mercury,' he said. Most of what is known about Mercury's surface and composition comes from NASA's MESSENGER probe, which assessed the makeup of the planet's crust from orbit. Both meteorites from the study, which Rider-Stokes analyzed with several instruments including an electron microscope, contain olivine and pyroxene, two iron-poor minerals confirmed by MESSENGER to be present on Mercury. The new analysis also revealed a complete lack of iron in the space rock samples, which is consistent with scientists' assumptions about the planet's surface. However, the meteorites contained only trace amounts of plagioclase, a mineral believed to dominate Mercury's surface. The biggest point of uncertainty, though, is still the meteorites' age. 'They are about 4.5 billion years old,' Rider-Stokes said, 'and most of Mercury's surface is only about 4 billion years old, so there's a 500 million-year difference.' However, he said he thinks this discrepancy is not sufficient to rule out a Mercurian origin, due to the limited reliability of MESSENGER's data, which has been also used to estimate the age of Mercury's surface layer. 'These estimates are based on impact cratering models and not absolute age dating, and therefore may not be entirely accurate,' Rider-Stokes said. 'It doesn't mean that these samples aren't good analogs for regional areas on the surface of Mercury, or the early Mercurian crust that is not visible on the modern surface of Mercury.' With more modern instruments now available, BepiColombo, the European Space Agency probe that will start studying Mercury in early 2027, may be able to answer long-standing questions about the planet, such as where it formed and whether it has any water. Having material confirmed to have come from other planetary bodies helps astronomers understand the nature of early solar system's building blocks, Rider-Stokes said, and identifying fragments of Mercury would be especially crucial since a mission to gather samples from the planet closest to the sun and bring them back would be extremely challenging and expensive. Sean Solomon, principal investigator for NASA's MESSENGER mission to Mercury, said in an email that he believes the two meteorites described in the recent paper likely did not originate from Mercury. Solomon, an adjunct senior research scientist at Columbia University in New York City, was not involved with the study. The primary reason Solomon cited for his doubts is that the meteorites formed much earlier than the best estimates for the ages of rocks now on Mercury's surface. But he said he thinks the samples still hold research value. 'Nonetheless, the two meteorites share many geochemical characteristics with Mercury surface materials, including little to no iron … and the presence of sulfur-rich minerals,' he added. 'These chemical traits have been interpreted to indicate that Mercury formed from precursor materials much more chemically reduced than those that formed Earth and the other inner planets. It may be that remnants of Mercury precursor materials still remain among meteorite parent bodies somewhere in the inner solar system, so the possibility that these two meteorites sample such materials warrants additional study.' Solomon also noted that it was difficult to persuade the planetary science community that there were samples from Mars in meteorite collections, and that it took precise matching of their chemistry with data about the surface of Mars taken by the Viking probes to convince researchers to take a closer look. Lunar meteorites were also not broadly acknowledged to be in meteorite collections until after the existence of Martian meteorites had been demonstrated in the 1980s, he added, even though the Apollo and Luna missions had returned abundant samples of lunar materials more than a decade earlier. Once samples are confirmed to be from a planetary body, Solomon said, they can provide crucial information not available from remote sensing by an orbiting spacecraft on the timing of key geological processes, the history of internal melting of the body, and clues to planet formation and early solar system processes. Rider-Stokes plans to continue the discussion around these meteorites at the annual meeting of the Meteoritical Society, which takes place in Perth this week. 'I'm going to discuss my findings with other academics across the world,' he said. 'At the moment, we can't definitively prove that these aren't from Mercury, so until that can be done, I think these samples will remain a major topic of debate across the planetary science community.'
Forbes
18 hours ago
- Science
- Forbes
When To See The Moon And Saturn Pair Up On Tuesday Night
The moon and Saturn, as seen from Kuwait City on October 14, 2024. (Photo by YASSER AL-ZAYYAT/AFP ... More via Getty Images) Look to the east shortly before midnight on Tuesday, July 15, and you'll see two of the most beautiful objects in the solar system shine together. A waning gibbous moon, by now rising late at night, will appear first, followed by the steady, golden glow of Saturn. They'll shine together all night, but as they rise is when to see them. Here's everything you need to know. Where And When To Look The close encounter — with the moon and Saturn just two degrees apart — will take place due east. The exact time both objects rise depends on your latitude (see below to check on the precise times for where you live), but from everywhere, the moon will appear first and be followed by Saturn. Around midnight local time, both the moon and Saturn will have climbed well above the eastern horizon and be moving into the southeast sky. They'll gradually move westward together and be visible until dawn. What You'll See The moon will be easily visible. About 70% lit, a waning gibbous moon will appear orange as it rises on the horizon. That's because of Rayleigh scattering. At this, the thickest part of Earth's atmosphere, shorter wavelengths of light, such as blue and violet, scatter away, while longer wavelengths — including red and orange — pass through more easily. Below the moon, Saturn will be dim but easily visible. It's no Venus in terms of brightness, but it's distinctive. Tuesday, July 15: The Moon Meets Saturn Observing Tips No special equipment is needed. However, binoculars will help you get a lovely close-up of the moon as it rises. For Saturn and its rings, you'll need any small telescope. Note that Saturn's rings are currently oriented nearly edge-on as a result of the planet's tilt and position in its orbit. Neptune is just above Saturn, but it is also too dim to see with the naked eye and requires a large telescope to observe. What's Next in the Night Sky Saturn will gradually become more prominent as it slowly brightens ahead of its opposition on September 21, when it will be at its biggest, brightest and best for telescopic viewing. By then, Saturn's rings will have opened up a bit and be a more dramatic sight. Meanwhile, keep an eye out for meteors from the Delta Aquarids and Alpha Capricornids, which are now active through early August. For exact timings, use a sunrise and sunset calculator for where you are, Stellarium Web for a sky chart and Night Sky Tonight: Visible Planets at Your Location for positions and rise/set times for planets. Wishing you clear skies and wide eyes.
Yahoo
08-05-2025
- Business
- Yahoo
'Eventually, all life on Earth will be destroyed by the sun': Elon Musk explains his drive to colonize Mars
Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Generate Key Takeaways When you buy through links on our articles, Future and its syndication partners may earn a commission. Artist's illustration of SpaceX Starships on Mars. | Credit: SpaceX Elon Musk is taking the long view. The billionaire SpaceX founder has long said that humanity needs to expand its footprint out into the solar system — specifically to Mars, which is the most suitable and reachable target — so that we won't go extinct if something bad should happen to Earth. That "if" only applies in the short term, however; over the very long haul, something bad will definitely happen. The sun is getting brighter and hotter as it ages, and a few hundred million years from now, this increased energy influx will strip off Earth's atmosphere and boil our oceans away. That will probably be the end for life as we know it. The coup de grace will come some five billion years from now, when our expanding red giant sun engulfs and incinerates poor little Earth. Musk referenced this sorry fate in a recent interview with Fox News host Jesse Watters, who asked the world's richest man why he's so fixated on the Red Planet. "That's one of the benefits of Mars, is life insurance for life collectively," Musk told Watters in the interview, which Fox News aired yesterday (May 6). "So, eventually, all life on Earth will be destroyed by the sun. The sun is gradually expanding, and so we do at some point need to be a multiplanet civilization, because Earth will be incinerated." Musk — who leads the Trump administration's cost- and regulation-cutting Department of Government Efficiency — estimated that we have about 450 million years "before it gets so hot that life is impossible." Related stories: — Will our solar system survive the death of our sun? — Red giant stars: Facts, definition & the future of the sun — Starship and Super Heavy: SpaceX's deep-space transportation for the moon and Mars That's a pretty long runway for SpaceX to complete the development and testing of Starship, the fully reusable megarocket that Musk thinks will make Mars settlement economically feasible. Starship, the biggest and most powerful rocket ever built, has flown eight times to date and twice this year so far. Both of the 2025 test missions, which launched in January and March, respectively, were partially successful. Starship's huge first stage booster, Super Heavy, performed well, but the vehicle's Ship upper stage exploded less than 10 minutes into flight. SpaceX is currently gearing up for Starship's next launch; the company has already test-fired the engines of the Super Heavy and Ship that will make Flight 9. But no target date has been announced.
