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Yahoo
06-04-2025
- Climate
- Yahoo
Lyrid meteor shower 2025 peaks this month: Could we be in for a surprise outburst this year?
When you buy through links on our articles, Future and its syndication partners may earn a commission. After a lull of some three and a half months, enthusiasts who watch the night sky specifically for "shooting" or "falling" stars will have something to look forward to this month. It will be the return of a faithful meteor shower, recognized as one of, if not the oldest known meteor display: the Lyrid meteors. While there are many dozens of meteor showers that occur during the course of the year, only ten are recognized as the 'principal' or very best meteor displays. The last such shower to take place was the Quadrantids back on Jan. 3. But since then, there have been no other noteworthy meteor showers to look for so far this year. That will change soon thanks to the Lyrid meteor shower. Dutch-American meteor expert Peter Jenniskens refers to the Lyrids as "The proverbial swallow of spring for observers in the northern hemisphere." This, he adds, follows "the low meteor rates in the cold months of February and March." This is a good year for observing the annual Lyrid meteor shower. Its peak should come on Tuesday morning, April 22, when moonlight will pose little interference. This year, the moon will be in a waning crescent phase, only 36 percent illuminated and will not rise until around 3:30 a.m. local daylight time. But although the Lyrids are a reliable meteor display, they nonetheless come with a disclaimer: They are often elusive; their surge of activity usually lasts just a few hours at most. According to the 2025 Meteor Shower Calendar of the International Meteor Organization (IMO), the time of maximum activity is anticipated to come at around 1330 Universal Time (UTC) or 9:30 a.m. ET. This is based on results collected from observations spanning the years 1988 to 2000. That predicted time would favor those living in Hawaii where predawn skies will be dark, as opposed to the contiguous U.S. where the sun will have already risen. However, in more recent years the time for the Lyrid peak has been more variable and if applied to this year, it might come as early as 10:30 UT to as late as 18:00 UT. If the former time rings true this year, it would mean that those living in the Mountain and Pacific time zones of the western U.S. would have an advantage in that the peak would come before the start of morning twilight. The meteors appear to radiate from around the brilliant star Vega in the constellation of Lyra the Lyre (hence the name "Lyrids"). Any meteor whose path, extended backward, comes within a few degrees of Vega is likely to be a Lyrid. While hardly a rich display — at their peak, one may be expected to average a meteor sighting about every three to five minutes; they're considered to be one of the weaker of the principal displays — Lyrid meteors are categorized as very bright and fairly fast. You can start watching for them beginning around midnight when Vega will be situated about one-third up in the east-northeast sky. When the first light of dawn is about to break at around 4:30 a.m., Vega has climbed to a position very high — almost overhead — above the eastern horizon. The Lyrids are also known for occasional surprises. There are a number of historic records of meteor displays believed to be Lyrids, notably in 687 B.C. and 15 B.C. in China (where records say "stars fell like rain"), and A.D. 1136 in Korea when "many stars flew from the northeast." On April 20, 1803, many townspeople in Richmond, Virginia, were roused from their beds by a fire alarm and were able to observe a very rich Lyrid display between 1 and 3 o'clock. The meteors "seemed to fall from every point in the heavens in such numbers as to resemble a shower of skyrockets." That stupendous Lyrid shower of 1803 was completely unexpected, primarily because very little was known about meteors in the 18th and early 19th centuries. But in 1867 Austrian astronomer, Edmund Weiss, and German astronomer, Johann Gottfried Galle made independent calculations that demonstrated that the progenitor of the Lyrid meteors is due to the cosmic dross that was left behind in the wake of Comet Thatcher, which circles the sun in a roughly 415-year orbit and was last seen in the spring of 1861. More recently, a brief outburst of about 90 per hour was seen in 1922. And then from Japan, 112 meteors (most of them were Lyrids) were seen in 67 minutes on April 22, 1945. Then, in 1982, the hourly rate unexpectedly reached 90 for a single hour and 180 to 300 for a few minutes. So maybe it wouldn't hurt to set the alarm clock for 3 or 4 a.m. on Tuesday morning, for a brief look out the window. Hey ... you never know. Normally this shower is above one-quarter peak strength two days before and after maximum, so if the weather in your area is unsettled on the morning of the 22nd, you still have a chance to catch a few Lyrids a day or two before or after the time of their peak activity. In addition to the Lyrids, there is also a possibility — albeit quite small — of sighting a brilliant fireball meteor that perhaps is even capable of dropping a meteorite. This declaration is based on two coincidences dating back to the 1960s. A shadow-casting fireball that passed over northern New Jersey on April 23, 1962, and an exploding meteor (bolide) seen on April 25, 1969 over England, Wales and Northern Ireland and dropped a nearly 10-pound (5 kg) stony meteorite. Both fireballs apparently have much in common. After orbital computations were made both in the U.S., and Great Britain, it was discovered that these dazzling meteors had remarkably similar orbits and had possibly originated either in the asteroid belt, or as perhaps the debris from an unknown short-period comet. Some astronomers believe that there might be a sparse stream of meteoroids which Earth might encounter during the final week of April. Some of these chunks of stone just might give rise to associated fireballs and perhaps even meteorite falls. RELATED STORIES: — Meteor showers 2025: When, where and how to see the best 'shooting stars' of the year — Meteor showers and shooting stars: Formation and history — Lyrid meteor shower 2025: When, where & how to see it Both the 1962 and 1969 fireballs emanated from a part of the sky near the constellation Corvus the Crow, which is composed of four moderately bright stars in the shape of a quadrilateral. Corvus can be found at nightfall about one-quarter up in the south-southeast part of the sky. It crosses the meridian shortly after 11 p.m. local daylight time and sets in the west-southwest around 4 a.m. So, if you're out and about during the overnight hours of April 23-24 and/or 24-25, be vigilant. If you're very lucky and nature is in a show-off mood, you just might catch sight of an outstandingly bright meteor blazing a south-to-north path across the night sky. Want to try and capture the Lyrids on camera? See our guides on how to photograph meteors and meteor showers the best cameras for astrophotography and best lenses for astrophotography. Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky and Telescope and other publications.
Yahoo
03-04-2025
- Science
- Yahoo
How a 'mudball' meteorite survived space to land in the jungles of Central America
When you buy through links on our articles, Future and its syndication partners may earn a commission. The pieces of a meteorite that fell in Costa Rica in 2019 are so unusual that scientists believe it had moved through space relatively unscathed — that is, until it encountered our planet. This is in stark contrast to other typical meteorites that show the wounds of having been in numerous collisions before reaching Earth. The meteorites were recovered from near the Costa Rican town of Aguas Zarcas, and are of a type referred to as 'mudballs', in the sense that they contain water-rich minerals. The findings have resulted in a reappraisal of these so-called mudball meteorites. It had been assumed that their high content of water-rich minerals would make them structurally weaker than other types of meteorites, rendering them more susceptible to damage or burning. But, "Apparently, [the presence of water-rich minerals] … does not mean they are weak," said Peter Jenniskens, a meteor astronomer from the SETI Institute and NASA Ames Research Center in California, in a statement. Scientists say the discovery rivals one of the largest discoveries of meteorites nearly 50 years prior. "Twenty-seven kilograms [60lbs] of rocks were recovered, making this the largest fall of its kind since similar meteorites fell near Murchison in Australia in 1969," said Jenniskens. The Murchison meteorite fall occurred just two months after the Apollo 11 mission. The recovered pieces showed that evidence of having been altered by liquid water on its parent body before an impact smashed apart that parent body and sent the Murchison and, later, the Aguas Zarcas meteoroids spinning into space. (Meteoroids are what we call meteorites when they are in space.) Video camera footage shows the 2019 mudball meteor entering the atmosphere from the west-north-west direction over Costa Rica at a steep, almost vertical angle of 81 degrees, and at a velocity of 9 miles (14.6 kilometers) per second. This steep angle allowed the meteor passed through less of Earth's atmosphere than it would have if it had approached on a shallower angle. That means more of the original meteoroid survived the fiery passage through the sky above Costa Rica. Based on the incoming meteor's trajectory, "We can tell that this object came from a larger asteroid low in the asteroid belt, likely from its outer regions," said Jenniskens. As it entered Earth's atmosphere, the rocky body is estimated to have been about 23.6 inches (60 centimeters) across. Friction with the atmosphere generated heat that melted its surface, stripping away much of the rock in a process known as ablation as it began to burn up. "It penetrated deep into Earth's atmosphere, until the surviving mass shattered at 15.5 miles (25 kilometers) above the Earth's surface, where it produced a bright flash that was detected by satellites in orbit," said Jenniskens. Those satellites were the Geostationary Operational Environment Satellites (GOES) 16 and 17 and their lightning detectors, which are Earth-observing satellites operated by NASA and the National Oceanic and Atmospheric Administration (NOAO). The fragments scattered themselves across the soft ground of Costa Rican jungle and grasslands, where they were subsequently found by meteorite hunters and volunteers. But the meteorites had a slightly unusual appearance. "The Aguas Zarcas fall produced an amazing selection of fusion-crusted stones with a wide range of shapes," said meteor scientist Laurence Garvie of the Buseck Center for Meteorite Studies at Arizona State University. "Some stones have a beautiful blue iridescence to the fusion crust." The fusion crust is the glassy, melted surface of a meteorite after it has endured ablation. Usually, meteorites have some flat sides, where they have broken apart as the result of stress fractures in the original meteoroid that were placed there by collisions in space with other meteoroids. The rounded rather than flat shapes of the Aguas Zarcas meteorites suggested that the meteoroid had travelled through space relatively unscathed after being blasted off its parent body. It has even been possible to calculate how long ago that was. Exposure to cosmic rays alters the composition of a meteoroid, so the degree of alteration tells us how long a meteoroid has been in space after breaking off its parent body. "The last collision experienced by this rock was two million years ago," said cosmochemist Kees Welton of UC Berkeley, who led this part of the study. "After getting loose, it took two million years to hit the tiny target of Earth, all the time avoiding getting cracked," added Jenniskens. This seems surprisingly recent, given the 4.6-billion-year history of the solar system. "We know of other Murchison-like meteorites that broke off at approximately the same time [as Murchison], and likely in the same event, but most broke much more recently," said Welton, with the Aguas Zarcas meteorites exemplifying the point. RELATED STORIES: — What are meteorites? — Watch (and hear!) a meteorite impact on doorbell camera video in a world 1st — Meteorites could have brought all 5 genetic 'letters' of DNA to early Earth Perhaps it is appropriate that the last word goes to Gerado Soto of the University of Costa Rica in San José, who draws similarities with the Murchison meteorite fall and its closeness in time to Apollo 11. "The fall of Aguas Zarcas was huge news in the country. No other fireball was as widely reported and then recovered as stones on the ground in Costa Rica in the past 150 years," he said. "The recovery of Aguas Zarcas [meteorites], too, was a small step for man, but a giant leap in meteoritics." The findings were published on March 29 in the journal Meteoritics & Planetary Science.
Yahoo
24-03-2025
- Science
- Yahoo
Meteorites and asteroids tracked back to their place of origin in the solar system
When you buy through links on our articles, Future and its syndication partners may earn a commission. Ten years ago, astronomers from various institutions, including NASA and SETI (Search for ExtraTerrestrial Intelligence), set out to map the asteroid belt by tracking meteorites as they blazed through Earth's atmosphere. To do this, they built a network of all-sky cameras across the globe, which they named the Global Fireball Observatory. "This has been a decade-long detective story, with each recorded meteorite fall providing a new clue," one of the project's founders, Peter Jenniskens of the SETI Institute and NASA Ames Research Center, said in a statement. "We now have the first outlines of a geologic map of the asteroid belt." Jennisken's colleague, Hadrien Devillepoix of Curtin University, added: "Others built similar networks spread around the globe, which together form the Global Fireball Observatory. Over the years, we have tracked the path of 17 recovered meteorite falls." The team's research was published on Monday (March 17) in the journal Meteoritics & Planetary Science. Meteorites are rocks from space that survive their fiery descent through Earth's atmosphere and reach the ground. More than just dazzling streaks of light as meteors, these ancient fragments are among the oldest materials in our solar system, originating from planets, asteroids, and comets. Most meteorites, however, originate from the solar system's main asteroid belt—a vast region between the orbits of Mars and Jupiter where more than a million asteroids circle the sun. Its formation remains a subject of debate, but astronomers believe it dates back around 4.5 billion years to the formation of the solar system's planets. These asteroids are thought to consist of leftover planetesimals, the building blocks of planets that never fully coalesced into a larger body. The asteroid belt contains debris fields known as clusters, which form when larger asteroids break apart due to random collisions. These smaller fragments remain grouped together and are called asteroid families. By measuring the radioactive elements present in a meteorite, astronomers can determine their age and match it to the "dynamical age" of asteroid debris fields. The dynamical age is the amount of time that has passed since an asteroid or group of asteroids was disrupted or scattered, determined by studying how the objects have spread out over time due to their movements and interactions, like gravitational forces or collisions. The more spread out the asteroids are, the older the debris field is likely to be. Essentially, it gives an estimate of how long it has been since the original disruption that caused the objects to scatter. By analyzing data gathered from watching the night sky and by using a combination of video footage and photographic observations of meteors, Devillepoix, Jenniskens, and their teams have tracked the origins of 75 meteorites in the asteroid belt. "Six years ago, there were just hints that different meteorite types arrived on different orbits, but now, the number of orbits (N) is high enough for distinct patterns to emerge," they wrote in their paper. One particularly interesting finding centers around iron-rich ordinary chondrite meteorites or "H chondrites," one of the most common types of meteorites that land on Earth. Their chemistry is considered primitive because they have never undergone melting and have experienced very few chemical interactions since their formation—making them valuable time capsules for understanding the early solar system. "We now see that 12 of the iron-rich ordinary chondrite meteorites (H chondrites) originated from a debris field called 'Koronis,' which is located low in the pristine main belt," said Jenniskens. "These meteorites arrived from low-inclined orbits with orbital periods consistent with this debris field. "By measuring the cosmic ray exposure age of meteorites, we can determine that three of these twelve meteorites originated from the Karin cluster in Koronis, which has a dynamical age of 5.8 million years, and two came from the Koronis2 cluster, with a dynamical age of 10-15 million years," he continued. 'One other meteorite may well measure the age of the Koronis3 cluster: about 83 million years.' The team also discovered that several groups of meteorites, including H-chondrites, originated from different regions in the asteroid belt. Some H-chondrites, with an age of about 6 million years, come from the Nele asteroid family, while others, with an exposure age of 35 million years, come from the inner main belt, likely from the Massalia asteroid family. They also found that the second most common group of meteorites, stony L chondrites, and the least abundant stony meteorites, LL chondrites, which are primarily from the inner main belt, trace back to the Flora and Hertha asteroid families. The L chondrites, in particular, experienced a violent origin 468 million years ago and are linked to a massive collision. Related Stories: —How are asteroids, space weather and space debris detected before they hit Earth? —Asteroids threatening Earth could be spotted by network of spacecraft near Venus' orbit, Chinese scientists say —If an asteroid really threatened the Earth, what would a planetary defense mission look like? While this provides one of the most comprehensive maps of the asteroid belt to date, not all meteorites in the database were assigned, and some assignments still carried uncertainty. But for Devillepoix and Jenniskens, this is just the beginning. "We are proud about how far we have come, but there is a long way to go," said Jenniskens. "Like the first cartographers who traced the outline of Australia, our map reveals a continent of discoveries still ahead when more meteorite falls are recorded.
