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Malay Mail
2 days ago
- Science
- Malay Mail
Astronomers spot hidden companion star orbiting blazing Betelgeuse
PARIS, July 22 — Since at least the time of the ancient Egyptians, people across the world have gazed up in awe at Betelgeuse, one of the brightest stars blazing in the night sky. Now astronomers have discovered that this red supergiant, known to many as the hunter's shoulder in the Orion constellation, is being orbited by a much smaller companion star, a study said on Monday. It is not the first time Betelgeuse has surprised stargazers. Seemingly out of nowhere, the giant star dramatically dimmed for five months between 2019 and 2020, leading some scientists to suggest it could soon die in an epic supernova explosion. Further observations revealed that this event — known as the 'Great Dimming' — was actually caused by material ejected from the surface that cooled part of the star, creating a dust cloud that blocked its light. But scientists could still not explain why Betelgeuse's brightness changes regularly, both on a 400-day cycle and another that lasts nearly six years. In a paper titled 'A Buddy for Betelgeuse' published in December, some researchers theorised that the longer variation could be caused by a hidden small star orbiting the behemoth. Astronomers using the Gemini North telescope in Hawaii have now discovered this elusive companion, according to a new study in The Astrophysical Journal Letters. Little buddy This companion has a mass around 1.5 times greater than our Sun, the research estimated. That means it is dwarfed by Betelgeuse, which is 1,000 times bigger than the Sun. The companion star is around four times the distance from Betelgeuse as the Earth is from the Sun, which is quite close for a stellar companion. The discovery is the first time such a close companion star has been detected orbiting a supergiant, according to a statement from the US research centre NOIRLab, which operates the Gemini Observatory. Betelgeuse is more than 10,000 times brighter than the Sun, its blinding light making spotting anything nearby difficult. Steve Howell, a Nasa scientist who led the research team, said previous 'papers that predicted Betelgeuse's companion believed that no one would likely ever be able to image it'. However the Gemini North telescope was able to spot the much smaller, dimmer star using a technique called speckle imaging. This involves assembling many images taken with short exposure times to overcome the distortions that Earth's atmosphere causes ground-bound telescopes. According to Greek myth, the giant hunter Orion claimed he would kill all the world's beasts, so Earth goddess Gaia sent a scorpion to kill him. God king Zeus then turned both Orion and the scorpion — Scorpius — into constellations. Earlier, ancient Egyptians included Betelgeuse in the constellation Osiris, their god of the dead. Even earlier, research has suggested that Indigenous Australians included Betelgeuse in their own constellations — and had noticed the star's varying brightness. — AFP
India Today
5 days ago
- Science
- India Today
Baby planet discovered by Nasa is shrinking. Its atmosphere is melting
Astronomers have witnessed a rare cosmic transformation — a young exoplanet shrinking before our to a new study using NASA's Chandra X-ray Observatory, the planet TOI 1227 b is losing its thick atmosphere under relentless bombardment from its parent star's intense about 330 light-years from Earth, TOI 1227 b orbits a red dwarf star in extremely close proximity — just one-fifth the distance that Mercury orbits the Sun. This tight orbit makes it especially vulnerable to the star's high-energy Estimated to be just 8 million years old, TOI 1227 b is among the youngest exoplanets ever observed, a true "baby" compared to Earth's 5-billion-year-old age.'This planet's atmosphere simply cannot survive the X-ray blast from its star,' said Attila Varga, lead author and Ph.D. student at the Rochester Institute of team found that TOI 1227 b is losing its atmosphere so rapidly that it could shed the equivalent of nearly two Earth masses within the next billion years — reducing in size and potentially evolving into a barren, rocky TOI 1227 b has a mass similar to Neptune but is three times larger in diameter, giving it a puffed-up, Jupiter-like appearance. Researchers believe this inflation is caused by the continuous X-ray exposure from its red dwarf host, TOI 1227, which is small in size but emits X-rays more intensely than our planet is estimated to lose one Earth atmosphere's worth of mass every 200 say the extreme conditions make the planet inhospitable to life, now or ever, as it lies far from the "habitable zone" where liquid water could study, published in The Astrophysical Journal, offers valuable insights into how harsh stellar environments shape the evolution of young exoplanets and may help explain how some planets lose their atmospheres early in life.- EndsTrending Reel
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Business Standard
16-07-2025
- Science
- Business Standard
NASA's Roman telescope to unlock 100,000 cosmic explosions in major survey
NASA's soon-to-launch Nancy Grace Roman Space Telescope is gearing up for a cosmic fireworks show unlike any other. According to a new study, one of its most ambitious sky surveys could uncover over 100,000 cosmic explosions — from brilliant supernovae to ravenous black holes — offering science enthusiasts and astrophysicists a potential treasure trove of discoveries. At the heart of this celestial hunt lies the High-Latitude Time-Domain Survey, an ambitious program that will observe the same vast patch of sky every five days over two years. These repeated scans will be stitched into detailed time-lapse 'movies' of the universe, capturing dynamic events as they unfold across billions of light-years. 'Whether you want to explore dark energy, dying stars, galactic powerhouses, or entirely new cosmic phenomena, this survey will be a gold mine,' said Benjamin Rose, assistant professor at Baylor University and lead author of the new study published in The Astrophysical Journal. Why it matters: a window into dark energy and ancient stars Among the most sought-after events are Type Ia supernovae — thermonuclear explosions of white dwarfs in binary systems. These stellar blasts shine with near-uniform brightness, making them perfect 'standard candles' to measure vast cosmic distances. Roman is expected to spot 27,000 of them, more than 10 times the total found by all previous surveys combined. Crucially, Roman's deep gaze will peer farther into the universe, and further back in time, than ever before. It could detect supernovae from over 11.5 billion years ago, potentially setting a new record for the farthest-known Type Ia explosion. Such data is critical in refining our understanding of dark energy, the mysterious force that's accelerating the universe's expansion. Evidence suggests that dark energy might have evolved over time, and Roman could help confirm this by mapping how the universe expanded across different epochs. 'Filling these data gaps could also fill in gaps in our understanding of dark energy,' said Rose. 'Roman will explore cosmic history in ways other telescopes can't.' Not just supernovae: a cosmic jackpot While Type Ia supernovae are the stars of the show for cosmologists, Roman will also observe about 60,000 core-collapse supernovae — explosions of massive stars that burn through their fuel and collapse. It may also detect feeding black holes, luminous kilonovae from neutron star mergers, and perhaps signatures of the universe's first stars, believed to self-destruct without leaving any trace. Distinguishing between these various cosmic explosions is a challenge. But scientists plan to use machine learning algorithms, trained on Roman's massive dataset, to sort through the incoming flood of data. 'Roman is going to collect a lot of cosmic 'bycatch'—phenomena that might be irrelevant to some but gold for others,' said Rebekah Hounsell, co-author of the study and research scientist at NASA's Goddard Space Flight Center. With science operations expected to begin in 2027, Roman is poised to deliver a new era of time-domain astronomy—watching the cosmos in motion, and catching its most spectacular moments in the act.
The Star
01-07-2025
- Science
- The Star
How the dance of death stars puts a new spin on the way suns are born
Some stars nearing the end of their lives slow their spin in a 'retirement solo' that not only shows the end is nigh but also how others are born. Chinese astronomers have used this cosmic dance to look into the Milky Way's past and find that stars born today spin much faster than those formed billions of years ago. Using data from Europe's Gaia space telescope and other sky surveys, researchers at the Changchun Observatory in northeastern China studied thousands of stars, each with a mass roughly 1½ times that of the sun. They found that as the Milky Way evolved, newly formed stars began spinning up to 10 times faster than their much older counterparts. That extra spin causes gas clouds to break into smaller fragments, making it harder for massive stars to take shape. The study, accepted for publication in The Astrophysical Journal, presents the first direct evidence that the galaxy's star-forming clouds have grown more turbulent over time. 'Our study shows that the angular momentum of stars in a certain mass range holds key clues to the Milky Way's history,' the team said in a statement on the observatory's website. 'It offers a new way to study how the galaxy has changed over time.' This shift in the star-forming environment could also reshape our galaxy, gradually favouring the birth of smaller, long-lived stars, while massive stars – and the explosive supernovae they trigger – could become rarer. Scientists have long relied on a star's chemical make-up, age, and motion to see back into the Milky Way's past. Stars are born spinning, and how fast they spin depends on the conditions in the clouds that formed them. Many stars slow down as they age. For instance, when the sun formed about 4.6 billion years ago, it likely took less than 10 days to complete a rotation. Today, it rotates once every 25 days at the equator. By the time it runs out of fuel and expands into a red giant, it will turn thousands of times more slowly and possibly take centuries to complete one spin. In the new study, the researchers from Changchun focused on stars between 1.4 and 1.8 times the sun's mass. Unlike the sun, these heavier stars hold on to much of their original spin for billions of years. Near the end of their lives, these stars expand dramatically. As their size increases, their spin slows. 'It's much like a ballerina extending her arms to slow down as she spins,' the team said, dubbing this final slowdown the star's 'retirement solo'. By using precise measurements from the Gaia mission, the team compared the angular momentum of thousands of such stars of various ages and found a striking pattern: younger stars spin much faster than older ones – not because the older stars slow down, but because they were born that way. The finding suggests that the Milky Way's star-forming environment has steadily grown more turbulent and energetic over the past 6 billion years, spinning up new stars with each generation. The team hopes future studies will refine models of how young stars develop just before they ignite. They also call for more data on stars with a wider range of chemical compositions, which could help reveal how different types of stars gain or lose spin during formation. - SOUTH CHINA MORNING POST
Saba Yemen
16-06-2025
- Science
- Saba Yemen
Astronomers Detect unique cosmic structure like no other
Washington – SABA: For the first time, astronomers have detected a massive cloud of energetic subatomic particles enveloping a giant galaxy cluster known as 'PLCK G287.0+32.9.' Galaxy clusters are among the largest known structures in the observable universe—vast gatherings of galaxies held together by gravity. This particular discovery has revealed a cloud spanning about 20 million light-years, nearly 200 times the diameter of our Milky Way galaxy. According to Al Jazeera Net, which reported on Monday, the findings were published in The Astrophysical Journal. The galaxy cluster lies about 5 billion light-years from Earth, and it was initially discovered in 2011 using a combination of terrestrial and space-based observatories. The new study, led by researchers from the Center for Astrophysics at Harvard University, was unveiled during a press conference at the 246th meeting of the American Astronomical Society in Anchorage, Alaska. The discovery relied on X-ray data collected by NASA's Chandra X-ray Observatory, appearing in the new imagery as blue and violet hues. Additional data came from the MeerKAT Radio Telescope in South Africa—one of the world's most powerful radio observatories—which provided the orange and yellow tones. Furthermore, visible light data was obtained using the Pan-STARRS telescope located atop Mount Haleakalā on the Hawaiian island of Maui, known for its clear and high-altitude skies. This exceptional cloud appears to be powered in an unusual way—through giant shockwaves and gas turbulence within the cluster. Unlike typical galaxy clusters, where such emissions are found mostly around the edges, this cloud completely envelops the entire cluster. These findings raise intriguing questions about the nature of such clouds and offer new insights into long-standing mysteries—such as: How do electrons in these clouds maintain their energy across such vast distances and time scales? This discovery marks a significant step forward in understanding cosmic structures and the energetic environments that shape our universe. Whatsapp Telegram Email Print more of (International)
