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The Star
7 days ago
- Science
- The Star
Chinese astronomers recorded details of dying star's explosion in 1408: study
Just after sunset on an October evening in 1408, six years into the reign of the Ming dynasty's Emperor Yongle, Chinese court astronomers spotted a mysterious new star glowing high in the southern sky, near the heart of the Milky Way. 'It was about the size of a cup-shaped oil lamp, with a pure yellow colour, smooth and bright,' according to Hanlin Academy scholar Hu Guang, in a formal report to the emperor that interpreted its appearance as a heavenly endorsement. 'We, your ministers, have encountered this auspicious sign, and respectfully offer our congratulations ... This splendid omen is truly a sign of an enlightened era,' Hu wrote, praising the ruler whose sweeping ambition had launched Zheng He's treasure fleets and extended China's reach as far as Africa. 'The star remained stationary and calm over 10 days of measurement and observation,' he noted, in a rediscovered memorial that has settled a long-standing debate among modern astronomers about the true nature of the 1408 event. While earlier records were too brief to draw firm conclusions, this official account confirms that the phenomenon was a nova – the slow, temporary brightening caused by a dying star – rather than a comet or meteor flashing through the sky. The discovery was reported last week by researchers from China, Germany, and Chile in peer-reviewed The Astronomical Journal. The unprecedented details, including the star's size and brightness, also helped the team to narrow down the star's possible position. The astronomers' analysis pointed to a stellar remnant named CK Vul, located between the modern constellations Cygnus and Vulpecula, as the most probable aftermath of the 1408 nova. Co-author Suzanne Hoffmann, from the University of Jena in Germany and the University of Science and Technology of China in Hefei, said the team hoped the paper would spark the interest of observational astronomers. None of the authors currently has access to telescope time, so they are unable to follow up on CK Vul and other candidate objects, to confirm whether their assessment is correct, she explained. Hoffmann said that such collaborations are common in science, pointing to the discovery of Neptune in 1846 as an example. French mathematician Urbain Le Verrier predicted its existence and calculated the position, but had no telescope. Le Verrier sent his calculations to the Berlin Observatory, where astronomers spotted Neptune, within just 1 degree of the predicted location – about the width of two full moons side by side in the night sky. According to Hoffmann and her colleagues, the star that caused the 1408 nova would have lived on as a white dwarf – the hot, dense core left behind by the death of a star like our Sun. More than 250 years later, it is likely to have merged with a companion star, in a dramatic event that led to the 1670 eruption now associated with CK Vul, the researchers wrote in the paper. However, CK Vul is hidden inside an opaque shell of dust and remains difficult to observe. Hoffmann said astronomers could still search for faint traces of the ancient eruption –such as expanding gas shells or glowing filaments – using infrared or X-ray telescopes. Over a span of more than 2,000 years, astronomers in ancient China carefully recorded celestial events, tracking everything from 'guest stars', as temporary bright objects were termed, to comets and eclipses with remarkable accuracy. One of the best known examples is the Crab Nebula, the remnant of a supernova explosion recorded by Chinese astronomers in 1054 as a brilliant 'guest star' that shone even in daylight for weeks and remained visible at night for nearly two years. Nearly a thousand years later, modern telescopes linked that ancient sighting to a glowing cloud of debris 6,500 light years away, showing how centuries-old records can still guide today's astrophysics discoveries. -- SOUTH CHINA MORNING POST
Belfast Telegraph
03-06-2025
- General
- Belfast Telegraph
New facility to detect millions of new solar system objects, say NI-led astronomers
The brand new facility at NSF–DOE Vera C. Rubin Observatory in Chile will revolutionise the world's knowledge of the solar system's 'small bodies': asteroids, comets and other minor planets. At the heart of the Rubin Observatory is the fastest moving telescope equipped with the world's largest digital camera. A single image from the telescope covers a patch of sky roughly 45 times the area of the full moon. This 'wide-fast-deep' system will spend the next ten years observing the night sky to produce the Legacy Survey of Space and Time (LSST). Astronomers say the system will provide unprecedented time-lapse footage of the cosmos and a powerful dataset with which to map the solar system. New open-source software has also been created to predict what discoveries are likely to be made, with a series of papers describing the software soon to be published by The Astronomical Journal. The group of astronomers has been led by Dr Meg Schwamb of Queen's University Belfast's School of Mathematics and Physics. Dr Schwamb said the world's knowledge of what objects fill the Earth's solar system 'is about to expand exponentially and rapidly'. QUB PhD student Joe Murtagh is one of the lead authors of the prediction studies and among those whose papers have been submitted to the Astronomical Journal. He said: 'It's very exciting – we expect that millions of new solar system objects will be detected and most of these will be picked up in the first few years of sky survey.' "With the LSST catalogue of solar system objects, our work shows that it will be like going from black-and-white television to brilliant colour.' Beyond just finding these new small bodies, Rubin Observatory will observe them multiple times in different optical filters, revealing their surface colours. Past solar system surveys, typically observed only in a single filter. To forecast which small bodies will be discovered, the team built Sorcha, the first end-to-end simulator that ingests Rubin's planned observing schedule. It applies assumptions on how Rubin Observatory observes and detects astronomical sources in its images with the best model of what the solar system and its small body reservoirs look like today. The team's simulations show that Rubin will map 127,000 near-Earth objects such as asteroids and comets whose orbits cross or approach the planet. It will also study over five million main-belt asteroids and 109,000 Jupiter Trojans, bodies which share Jupiter's orbit at stable 'Lagrange' points. Some 37,000 trans-Neptunian objects, which are residents of the distant Kuiper Belt, will also be mapped, along with around 1,500 to 2,000 Centaurs. The Sorcha code is open-source and freely available with the simulated catalogues, animations, and pre-prints of the papers publicly available at News Catch Up - Tuesday 3 June By making these resources available, the Sorcha team has enabled researchers worldwide to refine their tools and be ready for the flood of LSST data that Rubin will generate, advancing the understanding of the small bodies that illuminate the solar system like never before. Rubin Observatory is scheduled to unveil its first spectacular imagery at its 'First Look' event on June 23, offering the world an early glimpse of the survey's power. Full science operations are slated to begin later this year.
Yahoo
08-04-2025
- Science
- Yahoo
The truth is out there: Scientists want a new mission to hunt for life beyond Earth
Scientists want a new mission to hunt for life beyond Earth and the solar system. The Swiss university ETH Zurich's international Large Interferometer for Exoplanets mission would send telescopes to investigate the diversity of other worlds. The so-called LIFE mission would study the atmospheres of dozens of exoplanets with a similar temperature, radius and mass to Earth for signs of water and oxygen. "A single positive detection would change everything," physicist Dr. Daniel Angerhausen explained in a statement, "but even if we don't find life, we'll be able to quantify how rare — or common — planets with detectable biosignatures really might be." The mission concept is detailed in a new study published in The Astronomical Journal. The study reviews what astronomers could learn if there's 'no life detected' in future exoplanet surveys, relying on a 'Bayesian' statistical analysis to establish the minimum number of exoplanets that should be observed to get meaningful answers about the frequency of possibly inhabited worlds. Bayesian statistics has to do with determining the probability of an outcome based on other known probabilities, according to There are currently more than 5,800 confirmed exoplanets that exist beyond our solar system. Most of them orbit other stars and the majority of those that have been discovered are in our Milky Way galaxy. But, NASA believes that billions exist. The research found that if scientists examined between 40 and 80 exoplanets finding no life, they could conclude that fewer than 10 to 20 percent of similar planets host life. They said those conclusions would enable researchers to place an upper limit an estimated prevalence of life in the universe. 'This kind of result would be a turning point,' said Angerhausen, the study's lead author. 'Even if we don't find life, we'll finally be able to quantify how rare — or common — planets with detectable biosignatures really might be.' Still, they acknowledge that every observation comes with a certain level of uncertainty. For example, the mission could result in false negatives thanks to missed signs of life. The study authors say specific and measurable questions are necessary to address uncertainty, including 'which fraction of rocky planets in a solar system's habitable zone show clear signs of water vapor, oxygen, and methane.' "It's not just about how many planets we observe — it's about asking the right questions and how confident we can be in seeing or not seeing what we're searching for," Angerhausen said. "If we're not careful and are overconfident in our abilities to identify life, even a large survey could lead to misleading results."
The Independent
08-04-2025
- Science
- The Independent
The truth is out there: Scientists want a new mission to hunt for life beyond Earth
Scientists want a new mission to hunt for life beyond Earth and the solar system. The Swiss university ETH Zurich's international Large Interferometer for Exoplanets mission would send telescopes to investigate the diversity of other worlds. The so-called LIFE mission would study the atmospheres of dozens of exoplanets with a similar temperature, radius and mass to Earth for signs of water and oxygen. "A single positive detection would change everything," physicist Dr. Daniel Angerhausen explained in a statement, "but even if we don't find life, we'll be able to quantify how rare — or common — planets with detectable biosignatures really might be." The mission concept is detailed in a new study published in The Astronomical Journal. The study reviews what astronomers could learn if there's 'no life detected' in future exoplanet surveys, relying on a 'Bayesian' statistical analysis to establish the minimum number of exoplanets that should be observed to get meaningful answers about the frequency of possibly inhabited worlds. Bayesian statistics has to do with determining the probability of an outcome based on other known probabilities, according to There are currently more than 5,800 confirmed exoplanets that exist beyond our solar system. Most of them orbit other stars and the majority of those that have been discovered are in our Milky Way galaxy. But, NASA believes that billions exist. The research found that if scientists examined between 40 and 80 exoplanets finding no life, they could conclude that fewer than 10 to 20 percent of similar planets host life. They said those conclusions would enable researchers to place an upper limit an estimated prevalence of life in the universe. 'This kind of result would be a turning point,' said Angerhausen, the study's lead author. 'Even if we don't find life, we'll finally be able to quantify how rare — or common — planets with detectable biosignatures really might be.' Still, they acknowledge that every observation comes with a certain level of uncertainty. For example, the mission could result in false negatives thanks to missed signs of life. The study authors say specific and measurable questions are necessary to address uncertainty, including 'which fraction of rocky planets in a solar system's habitable zone show clear signs of water vapor, oxygen, and methane.' "It's not just about how many planets we observe — it's about asking the right questions and how confident we can be in seeing or not seeing what we're searching for," Angerhausen said. "If we're not careful and are overconfident in our abilities to identify life, even a large survey could lead to misleading results."
WIRED
25-03-2025
- Science
- WIRED
Scientists Observe Carbon Dioxide on Planets Outside the Solar System for the First Time
Mar 25, 2025 4:00 AM The findings provide strong evidence that four giant exoplanets 130 light-years from Earth formed much like Jupiter and Saturn. An illustration of the James Webb Space Telescope. Illustration: dima_zel/NASA Carbon dioxide has been detected on a planet outside our solar system for the first time. The gas has been observed directly by the James Webb Space Telescope on four exoplanets, all belonging to the HR 8799 system, located 130 light-years from Earth. The detection of CO 2 offers clues as to how distant planets form, with the observations providing strong evidence that these four giant planets formed in much the same way as Jupiter and Saturn, through the slow formation of solid cores. The findings were published in the most recent issue of The Astronomical Journal. 'By detecting these strong formations of carbon dioxide, we have shown that there is a considerable fraction of heavier elements, such as carbon, oxygen, and iron, in the atmospheres of these planets,' William Balmer, an astrophysicist at Johns Hopkins University and lead author of the paper, said in a statement to NASA. 'Given what we know about the star they orbit, this probably indicates that they formed by core accretion, which, for planets we can see directly, is an exciting conclusion.' HR 8799 is a system that was born 30 million years ago, and so is young compared to our solar system, which has existed for 4.6 billion years. Still hot from their violent formation, the planets of HR 8799 emit large amounts of infrared light. This provides scientists with valuable data on how their formation compares to that of a star or brown dwarf, the term given to large gaseous planets that fail to develop into stars. 'Our hope with this type of research is to understand our own solar system, life, and ourselves in comparison to other exoplanetary systems, so we can contextualize our existence,' Balmer said. 'We want to take pictures of other solar systems and see how they are similar to or different from ours. From there, we can try to understand how strange our solar system really is, or how normal it is.' Carbon dioxide has been an essential ingredient for development of life on Earth, making it a key target in the search for life elsewhere in outer space. Plus, because CO 2 condenses into tiny ice particles in the deep cold of space, its presence can shed light on planetary formation. Jupiter and Saturn are thought to have formed through a process in which a bunch of tiny icy particles coalesced to form a solid core, which then absorbed gas to grow into the gas giants we know today. 'We have other lines of evidence that point to the formation of these four planets in HR 8799 by this bottom-up approach,' Laurent Pueyo, an astronomer at the Space Telescope Science Institute and coauthor of the paper, said in a statement to NASA. 'How common is this in long-period planets that we can directly image? We don't know yet, but we propose further observations through Webb, inspired by our carbon dioxide diagnostics, to answer this question.' Unlocking the James Webb Space Telescope's Potential The James Webb Space Telescope should also be given its flowers, as it has shown that it is capable of doing more than inferring the atmospheric composition of exoplanets from measurements of starlight; in fact, it has demonstrated its ability to directly analyze the chemical composition of atmospheres as far away as these. Normally, the JWST can barely detect an exoplanet as it crosses in front of its host star, due to the great distance that separates us. But on this occasion, direct observation was made possible by the JWST's coronagraphs—instruments that block starlight to reveal otherwise hidden worlds. 'It's like putting your thumb in front of the sun when you look at the sky,' Balmer said. This setting, similar to a solar eclipse, allowed the team to look for infrared light at wavelengths coming from the planet that reveal specific gases and other atmospheric details. 'These giant planets have very important implications,' Balmer said. 'If these huge planets act like bowling balls cruising through our solar system, they can disrupt, protect or, in a sense, do both to planets like ours. Therefore, better understanding their formation is crucial to understanding the formation, survival, and habitability of Earth-like planets in the future.' This story originally appeared on WIRED en Español and has been translated from Spanish.
