Latest news with #exoplanets
Sustainability Times
4 days ago
- Science
- Sustainability Times
'I Was Convinced We'd Found Aliens': Scientists Backtrack on K2-18b Breakthrough Before Revealing the Devastating Truth
IN A NUTSHELL 🔍 Researchers re-examined data on K2-18b , broadening the pool of atmospheric chemicals from 20 to 90, weakening earlier claims of alien life. , broadening the pool of atmospheric chemicals from 20 to 90, weakening earlier claims of alien life. 🌌 Initial excitement was sparked by the detection of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), considered potential biosignatures. and dimethyl disulfide (DMDS), considered potential biosignatures. 📊 Updated studies found no statistically significant evidence of these compounds, highlighting the need for robust scientific methods . . 🔭 Advanced technology and future observations are crucial for gaining a clearer understanding of exoplanetary atmospheres and the potential for life. In recent years, the search for extraterrestrial life has captivated scientists and the public alike, with the focus often landing on distant exoplanets like K2-18b. Located 124 light-years away in the Leo constellation, this intriguing planet resides within the habitable zone of its star, sparking hope for the potential presence of life. However, recent research has cast doubt on earlier claims of alien life signs on K2-18b, urging scientists to remain cautious. This article delves into the ongoing debate, examining updated data, scientific methodologies, and the future of such explorations. Re-evaluating the Evidence: A Shift in Perspective The initial excitement over potential biosignatures on K2-18b stemmed from the detection of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) by astronomers using the James Webb Space Telescope. These compounds, known to be produced by marine algae on Earth, were considered potential indicators of life. However, a re-examination of the data by researchers, including former students of Nikku Madhusudhan, has altered this perspective. By broadening the pool of possible atmospheric chemicals from 20 to 90, the team found that the signals no longer uniquely pointed to biological explanations. Madhusudhan and his colleagues highlighted the necessity of employing alternative statistical models to re-evaluate the evidence. Their updated approach included a list of 650 potential atmospheric chemicals, underscoring the complexity of identifying biosignatures. This re-evaluation has significantly weakened the case for a biological explanation, illustrating the importance of skepticism and thorough analysis in scientific discovery. 'Super-Earths Are Everywhere': New Study Reveals These Giant Alien Worlds Are Far More Common Than Scientists Ever Imagined Scientific Methodologies: The Quest for Precision The search for life on exoplanets like K2-18b relies heavily on precise scientific methodologies. Astronomers analyze distant planets by observing their transit across host stars, which allows them to study how molecules in the atmosphere absorb specific wavelengths of starlight. This method, while powerful, is fraught with challenges. Recent studies combining observations in both near-infrared and mid-infrared wavelengths found no statistically significant evidence for DMS or DMDS, further complicating the case for life. Postdoctoral researcher Rafael Luque and Oxford astrophysicist Jake Taylor contributed to this discourse by employing different statistical methods. Taylor's basic statistical approach found no strong signs of biosignatures, emphasizing the need for robust methods and comprehensive data. The inconsistencies in findings highlight the complexities involved in interpreting astronomical data, urging scientists to continuously refine their techniques. 'Doomsday Coming Sooner Than You Think': This Groundbreaking Study Reveals the Imminent Threat Facing Humanity and Why We Need to Act Now The Role of Advanced Technology in Space Exploration Advanced technology plays a pivotal role in unraveling the mysteries of distant exoplanets. The James Webb Space Telescope, with its ability to capture detailed atmospheric data, has been instrumental in the ongoing research of K2-18b. However, as Madhusudhan pointed out, more data is needed to draw definitive conclusions. As technology evolves, so too does the precision and scope of astronomical research. Future observations, made possible by technological advancements, will enhance our understanding of planets like K2-18b. As more data is collected over the next year, scientists hope to paint a clearer picture of the atmospheric composition and potential for life. This ongoing technological evolution promises to deepen our knowledge of the universe and our place within it. 'They're Coming From Space!': Mysterious Radio Signals Repeating Every 2 Hours Identified in That Distant Star System Looking Forward: The Future of Exoplanetary Research As the debate over K2-18b continues, the scientific community remains committed to uncovering the truth about alien life. The conflicting findings underscore the need for a cautious approach, where claims are rigorously tested and re-tested. The journey to discover extraterrestrial life is a marathon, not a sprint, demanding patience and perseverance. Looking forward, the collection of new data and the refinement of analytical methods will be crucial. The pursuit of knowledge about exoplanets like K2-18b serves as a reminder of humanity's insatiable curiosity and the endless possibilities that lie beyond our home planet. As we continue to explore the cosmos, what new revelations await us on distant worlds? Our author used artificial intelligence to enhance this article. Did you like it? 4.3/5 (26)
CNA
6 days ago
- Science
- CNA
Scientists puzzled by giant planet detected orbiting tiny star
WASHINGTON :Astronomers have spotted a cosmic mismatch that has left them perplexed - a really big planet orbiting a really small star. The discovery defies current understanding of how planets form. The star is only about a fifth the mass of the sun. Stars this size should host small planets akin to Earth and Mars under the leading theories on planetary formation. But the one detected in orbit around this star is much larger - in fact, as big as Saturn, the second-largest planet in our solar system. The star, named TOI-6894, is located roughly 240 light-years from Earth in the constellation Leo. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). It is the smallest-known star to host a large planet, about 40 per cent smaller than the two previous record holders. "The question of how such a small star can host such a large planet is one that this discovery raises - and we are yet to answer," said astronomer Edward Bryant of the University of Warwick in England, lead author of the study published on Wednesday in the journal Nature Astronomy. Planets beyond our solar system are called exoplanets. The one orbiting TOI-6894 is a gas giant, like Saturn and Jupiter in our solar system, rather than a rocky planet like Earth. The birth of a planetary system begins with a large cloud of gas and dust - called a molecular cloud - that collapses under its own gravity to form a central star. Leftover material spinning around the star in what is called a protoplanetary disk forms planets. Smaller clouds yield smaller stars, and smaller disks contain less material to form planets. "In small clouds of dust and gas, it's hard to build a giant planet," said exoplanet scientist and study co-author Vincent Van Eylen of University College London's Mullard Space Science Laboratory. "This is because to build a giant planet, you need to quickly build a large planet core and then quickly accrete (accumulate) a lot of gas on top of that core. But there's only so much time to do it before the star starts shining and the disk rapidly disappears. In small stars, we think there's simply not enough mass available to build a giant planet quickly enough before the disk disappears," Van Eylen added. No known planet is larger than its host star, and that is the case here as well, though the two are much closer in size than usual. While the sun's diameter is 10 times larger than our solar system's largest planet Jupiter, TOI-6894's diameter is just 2.5 times greater than its only known planet. The star is a red dwarf, the smallest type of regular star and the most common kind found in the Milky Way galaxy. "Given these stars are very common, there may be many more giant planets in the galaxy than we thought," Bryant said. The star is about 21 per cent the mass of the sun and much dimmer. In fact, the sun is about 250 times more luminous than TOI-6894. "These findings suggest that even the smallest stars in the universe can in some cases form very large planets. That forces us to rethink some of our planet formation models," Van Eylen said. The planet is located about 40 times closer to its star than Earth is to the sun, completing an orbit in approximately three days. Its proximity to the star means the planet's surface is quite hot, though not as hot as gas giants called "hot Jupiters" detected orbiting similarly close to bigger stars. Its diameter is slightly larger than Saturn and a bit smaller than Jupiter, though it is less dense than them. Its mass is 56 per cent that of Saturn and 17 per cent that of Jupiter. The main data used in studying the planet came from NASA's orbiting Transiting Exoplanet Survey Satellite, or TESS, and the European Southern Observatory's Chile-based Very Large Telescope, or VLT. The researchers hope to better understand the planet's composition with observations planned over the next year using the James Webb Space Telescope. "We expect it to have a massive core surrounded by a gaseous envelope made up of predominantly hydrogen and helium gas," Bryant said.
Reuters
6 days ago
- General
- Reuters
Scientists puzzled by giant planet detected orbiting tiny star
WASHINGTON, June 4 (Reuters) - Astronomers have spotted a cosmic mismatch that has left them perplexed - a really big planet orbiting a really small star. The discovery defies current understanding of how planets form. The star is only about a fifth the mass of the sun. Stars this size should host small planets akin to Earth and Mars under the leading theories on planetary formation. But the one detected in orbit around this star is much larger - in fact, as big as Saturn, the second-largest planet in our solar system. The star, named TOI-6894, is located roughly 240 light-years from Earth in the constellation Leo. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). It is the smallest-known star to host a large planet, about 40% smaller than the two previous record holders. "The question of how such a small star can host such a large planet is one that this discovery raises - and we are yet to answer," said astronomer Edward Bryant of the University of Warwick in England, lead author of the study published on Wednesday in the journal Nature Astronomy. Planets beyond our solar system are called exoplanets. The one orbiting TOI-6894 is a gas giant, like Saturn and Jupiter in our solar system, rather than a rocky planet like Earth. The birth of a planetary system begins with a large cloud of gas and dust - called a molecular cloud - that collapses under its own gravity to form a central star. Leftover material spinning around the star in what is called a protoplanetary disk forms planets. Smaller clouds yield smaller stars, and smaller disks contain less material to form planets. "In small clouds of dust and gas, it's hard to build a giant planet," said exoplanet scientist and study co-author Vincent Van Eylen of University College London's Mullard Space Science Laboratory. "This is because to build a giant planet, you need to quickly build a large planet core and then quickly accrete (accumulate) a lot of gas on top of that core. But there's only so much time to do it before the star starts shining and the disk rapidly disappears. In small stars, we think there's simply not enough mass available to build a giant planet quickly enough before the disk disappears," Van Eylen added. No known planet is larger than its host star, and that is the case here as well, though the two are much closer in size than usual. While the sun's diameter is 10 times larger than our solar system's largest planet Jupiter, TOI-6894's diameter is just 2.5 times greater than its only known planet. The star is a red dwarf, the smallest type of regular star and the most common kind found in the Milky Way galaxy. "Given these stars are very common, there may be many more giant planets in the galaxy than we thought," Bryant said. The star is about 21% the mass of the sun and much dimmer. In fact, the sun is about 250 times more luminous than TOI-6894. "These findings suggest that even the smallest stars in the universe can in some cases form very large planets. That forces us to rethink some of our planet formation models," Van Eylen said. The planet is located about 40 times closer to its star than Earth is to the sun, completing an orbit in approximately three days. Its proximity to the star means the planet's surface is quite hot, though not as hot as gas giants called "hot Jupiters" detected orbiting similarly close to bigger stars. Its diameter is slightly larger than Saturn and a bit smaller than Jupiter, though it is less dense than them. Its mass is 56% that of Saturn and 17% that of Jupiter. The main data used in studying the planet came from NASA's orbiting Transiting Exoplanet Survey Satellite, or TESS, and the European Southern Observatory's Chile-based Very Large Telescope, or VLT. The researchers hope to better understand the planet's composition with observations planned over the next year using the James Webb Space Telescope. "We expect it to have a massive core surrounded by a gaseous envelope made up of predominantly hydrogen and helium gas," Bryant said.
The Sun
6 days ago
- General
- The Sun
Super Earth in ‘Goldilocks zone' discovered with new alien-hunting tool – now it will search for more habitable planets
SCIENTISTS have stumbled across a new Super-Earth that orbits inside its star's habitable zone with a new alien-hunting tool. Searching for Earth -like planets - and Earth-like life - is the ultimate goal for planetary science. 3 3 And finding planets that lie in the Goldilocks zone of their sun-like stars – where the conditions are 'just right' to possibly host life – is key to that mission. An international team of scientists, led by the Yunnan Observatories of the Chinese Academy of Sciences (CAS), have used a new technique to find these potentially habitable worlds. It's called the Transit Timing Variation (TTV) technique - which looks for changes in the predicted transit times of an exoplanet. If the time changes, it could indicate the presence of other unseen planets in the system that are gravitationally influencing the transiting planet. The technique is a good way to detect smaller planets that would otherwise be difficult to find By analysing the TTV signals of Kepler-725b, a gas giant planet in the same system, the team were able to find its hidden sister planet Kepler-725c, according to a new study published in Nature Astronomy. Researchers said the technique offers a promising alternative in the hunt for "Earth 2.0." Kepler-725c has 10 times the mass of Earth and is located in the habitable zone of the sun-like star Kepler-725. It receives roughly 1.4 times the solar radiation than Earth does. Best-ever sign of ALIEN life found on distant planet as scientists '99.7% sure of astounding biological activity signal' Located in the Lyra constellation, the Super Earth planet completes an orbit of its nearby star every 207.5 days. During part of this orbit, the planet enters its star's habitable zone - meaning it could host alien life. Little else is known about the planet so far. It is the first time it has been used to discover a Super-Earth, a type of rocky exoplanet that is larger than Earth but too small to be considered a gas giant like Neptune. Astronomers have relied on alternative techniques to find exoplanets for decades. Like the transit method, where astronomers track how the light from a host star dims when a planet passes in front of it. Or through radial velocity (RV) observations, which is when scientists watch the slight wobble of a star as it interacts with the gravitational pull of an orbiting planet. However, both of these techniques have their flaws and make it difficult to detect planets with long orbital periods. The transit approach, for example, requires a planet's orbit to align exactly with our line of sight from Earth. Whereas the RV method requires extremely high-precision measurements, which makes it harder to find smaller planets.
New York Times
02-06-2025
- General
- New York Times
Scientific Discoveries, and Dreams, in the Balance
One of the joys of science journalism is in seeing dreams come true — watching scientists push their career chips across the table, on behalf of a vision or a mission that will take years to achieve, and finally win. Their stories are sagas of passion, curiosity and sacrifice. William Borucki, a space scientist who didn't have a Ph.D., and his collaborator, David Koch, spent 20 years trying to convince NASA that a space telescope could find planets by detecting their shadows on other stars. NASA rejected their proposal five times until ultimately relenting. 'It's a wonderful thing to have someone tell you over and over again everything that is wrong with your experiment,' Mr. Borucki once said. He changed the galaxy: The Kepler satellite, launched in 2009, discovered more than 4,000 exoplanets in a small patch of the Milky Way, suggesting that there were as many as 40 billion potentially habitable planets in the Milky Way alone. Scientists involved in the effort to detect the space-time ripples known as gravitational waves tell a similar story. In the 1970s and 80s, when Rainer Weiss, a physicist at M.I.T., and Kip Thorne of Caltech started talking to the National Science Foundation about the possibility of observing these waves, 'everybody thought we were out of our minds,' Dr. Weiss once said. Want all of The Times? Subscribe.
