Latest news with #HabitableWorldsObservatory
Economic Times
4 days ago
- General
- Economic Times
Is Europa, Jupiter's ocean moon, the final haven for life once the sun dies? Here's what a recent study shows
In approximately 4.5 billion years, as the sun transforms into a red giant and engulfs Earth, Jupiter's moon Europa may offer a temporary refuge. Research suggests Europa's icy shell will sublimate, potentially creating a fleeting water vapor atmosphere lasting up to 200 million years. This could provide a brief window for habitable conditions and detectable biosignatures. Tired of too many ads? Remove Ads How does the red giant sun affect Europa? Tired of too many ads? Remove Ads Can Europa's oceans survive the heat? What are the chances of finding life or biosignatures? FAQs The most intriguing question is what will happen to life in our solar system after the sun sun will become a red giant and wipe out Earth in roughly 4.5 billion years. The cold moons of the outer solar system may provide humanity a fleeting chance to survive, while new science offers us a glimpse of a distant, dying future. Europa , one of Jupiter's moons, might serve as a temporary safe at Cornell University's Carl Sagan Institute reached this conclusion and published their findings in the journal Monthly Notices of the Royal Astronomical sun will reach the end of its life cycle in roughly 4.5 billion years. Its hydrogen fusion core will grow, inflating the star's outer atmosphere to enormous proportions. It will enlarge and turn into a red giant star, burning up Earth and swallowing up Venus and Mercury, as per a report by the sun enters this new stage of life, the habitable zone, the region where the radiation influx is just right to support liquid water on a planet's surface, will gradually move Jupiter remains an inhospitable giant ball of gas, some of its moons could potentially lead to a habitable the ice-covered moon of Jupiter, will receive a lot of heat. Jupiter will become hotter and reflect more sunlight, which will give the small moon its own source of heat besides the giant sun's scientists discovered that the oceans below will evaporate while the icy outer shell sublimates. Because it will receive the most heat, the side of Europa facing Jupiter will experience the most sublimation, as per a report by the anti-Jupiter side of Europa, the rate of water loss will be slower in the northern and southern latitudes. According to the researchers, this might produce a thin layer of water vapor that lasts for 200 million years or researchers discovered that biosignatures may be detectable on icy moons of red giant stars. Although there are a number of promising candidates, we have not yet detected any exomoons with resolving power to investigate these moons' atmospheric features may come from future observations using the James Webb Space Telescope or the proposed Habitable Worlds Observatory. Even though the likelihood of finding life is narrow, it does expand the range of potential places for our search because there might still be refuges around almost-dead but only for a short time up to 200 million years in isolated areas where water loss is underground oceans and temporary water vapor atmosphere may provide brief habitable conditions.
NDTV
4 days ago
- Health
- NDTV
New Model Helps To Figure Out Which Distant Planets May Host Life
The search for life beyond Earth is a key driver of modern astronomy and planetary science. The U.S. is building multiple major telescopes and planetary probes to advance this search. However, the signs of life – called biosignatures – that scientists may find will likely be difficult to interpret. Figuring out where exactly to look also remains challenging. I am an astrophysicist and astrobiologist with over 20 years of experience studying extrasolar planets – which are planets beyond our solar system. My colleagues and I have developed a new approach that will identify the most interesting planets or moons to search for life and help interpret potential biosignatures. We do this by modeling how different organisms may fare in different environments, informed by studies of limits of life on Earth. New Telescopes To Search For Life Astronomers are developing plans and technology for increasingly powerful space telescopes. For instance, NASA is working on its proposed Habitable Worlds Observatory, which would take ultrasharp images that directly show the planets orbiting nearby stars. My colleagues and I are developing another concept, the Nautilus space telescope constellation, which is designed to study hundreds of potentially Earthlike planets as they pass in front of their host stars. These and other future telescopes aim to provide more sensitive studies of more alien worlds. Their development prompts two important questions: 'Where to look?' and 'Are the environments where we think we see signs of life actually habitable?' The strongly disputed claims of potential signs of life in the exoplanet K2-18b, announced in April 2025, and previous similar claims in Venus, show how difficult it is to conclusively identify the presence of life from remote-sensing data. When Is An Alien World Habitable? Oxford Languages defines 'habitable' as 'suitable or good enough to live in.' But how do scientists know what is 'good enough to live in' for extraterrestrial organisms? Could alien microbes frolic in lakes of boiling acid or frigid liquid methane, or float in water droplets in Venus' upper atmosphere? To keep it simple, NASA's mantra has been 'follow the water.' This makes sense – water is essential for all Earth life we know of. A planet with liquid water would also have a temperate environment. It wouldn't be so cold that it slows down chemical reactions, nor would it be so hot that it destroys the complex molecules necessary for life. However, with astronomers' rapidly growing capabilities for characterizing alien worlds, astrobiologists need an approach that is more quantitative and nuanced than the water or no-water classification. A Community Effort As part of the NASA-funded Alien Earths project that I lead, astrobiologist Rory Barnes and I worked on this problem with a group of experts – astrobiologists, planetary scientists, exoplanet experts, ecologists, biologists and chemists – drawn from the largest network of exoplanet and astrobiology researchers, NASA's Nexus for Exoplanet System Science, or NExSS. Over a hundred colleagues provided us with ideas, and two questions came up often: First, how do we know what life needs, if we do not understand the full range of extraterrestrial life? Scientists know a lot about life on Earth, but most astrobiologists agree that more exotic types of life – perhaps based on different combinations of chemical elements and solvents – are possible. How do we determine what conditions those other types of life may require? Second, the approach has to work with incomplete data. Potential sites for life beyond Earth – 'extrasolar habitats' – are very difficult to study directly, and often impossible to visit and sample. For example, the Martian subsurface remains mostly out of our reach. Places like Jupiter's moon Europa's and Saturn's Moon Enceladus' subsurface oceans and all extrasolar planets remain practically unreachable. Scientists study them indirectly, often only using remote observations. These measurements can't tell you as much as actual samples would. To make matters worse, measurements often have uncertainties. For example, we may be only 88% confident that water vapor is present in an exoplanet's atmosphere. Our framework has to be able to work with small amounts of data and handle uncertainties. And, we need to accept that the answers will often not be black or white. A New Approach To Habitability The new approach, called the quantitative habitability framework, has two distinguishing features: First, we moved away from trying to answer the vague 'habitable to life' question and narrowed it to a more specific and practically answerable question: Would the conditions in the habitat – as we know them – allow a specific (known or yet unknown) species or ecosystem to survive? Even on Earth, organisms require different conditions to survive – there are no camels in Antarctica. By talking about specific organisms, we made the question easier to answer. Second, the quantitative habitability framework does not insist on black-or-white answers. It compares computer models to calculate a probabilistic answer. Instead of assuming that liquid water is a key limiting factor, we compare our understanding of the conditions an organism requires (the 'organism model') with our understanding of the conditions present in the environment (the 'habitat model'). Both have uncertainties. Our understanding of each can be incomplete. Yet, we can handle the uncertainties mathematically. By comparing the two models, we can determine the probability that an organism and a habitat are compatible. As a simplistic example, our habitat model for Antarctica may state that temperatures are often below freezing. And our organism model for a camel may state that it does not survive long in cold temperatures. Unsurprisingly, we would correctly predict a near-zero probability that Antarctica is a good habitat for camels. We had a blast working on this project. To study the limits of life, we collected literature data on extreme organisms, from insects that live in the Himalayas at high altitudes and low temperatures to microorganisms that flourish in hydrothermal vents on the ocean floor and feed on chemical energy. We explored, via our models, whether they may survive in the Martian subsurface or in Europa's oceans. We also investigated if marine bacteria that produce oxygen in Earth's oceans could potentially survive on known extrasolar planets. Although comprehensive and detailed, this approach makes important simplifications. For example, it does not yet model how life may shape the planet, nor does it account for the full array of nutrients organisms may need. These simplifications are by design. In most of the environments we currently study, we know too little about the conditions to meaningfully attempt such models – except for some solar system bodies, such as Saturn's Enceladus. The quantitative habitability framework allows my team to answer questions like whether astrobiologists might be interested in a subsurface location on Mars, given the available data, or whether astronomers should turn their telescopes to planet A or planet B while searching for life. Our framework is available as an open-source computer model, which astrobiologists can now readily use and further develop to help with current and future projects. If scientists do detect a potential signature of life, this approach can help assess if the environment where it is detected can actually support the type of life that leads to the signature detected. Our next steps will be to build a database of terrestrial organisms that live in extreme environments and represent the limits of life. To this data, we can also add models for hypothetical alien life. By integrating those into the quantitative habitability framework, we will be able to work out scenarios, interpret new data coming from other worlds and guide the search for signatures of life beyond Earth – in our solar system and beyond. (Authors: Daniel Apai, Associate Dean for Research and Professor of Astronomy and Planetary Sciences, University of Arizona) (Disclosure Statement: Daniel Apai receives funding from NASA, Heising-Simons Foundation, Department of Defense, Space Telescope Science Institute, and the University of Arizona, and leads the NASA-funded Alien Earths astrobiology research team that developed the framework described here. He is affiliated with the Steward Observatory and Lunar and Planetary Laboratory of The University of Arizona)
Yahoo
5 days ago
- Health
- Yahoo
New model helps to figure out which distant planets may host life
The search for life beyond Earth is a key driver of modern astronomy and planetary science. The U.S. is building multiple major telescopes and planetary probes to advance this search. However, the signs of life – called biosignatures – that scientists may find will likely be difficult to interpret. Figuring out where exactly to look also remains challenging. I am an astrophysicist and astrobiologist with over 20 years of experience studying extrasolar planets – which are planets beyond our solar system. My colleagues and I have developed a new approach that will identify the most interesting planets or moons to search for life and help interpret potential biosignatures. We do this by modeling how different organisms may fare in different environments, informed by studies of limits of life on Earth. Astronomers are developing plans and technology for increasingly powerful space telescopes. For instance, NASA is working on its proposed Habitable Worlds Observatory, which would take ultrasharp images that directly show the planets orbiting nearby stars. My colleagues and I are developing another concept, the Nautilus space telescope constellation, which is designed to study hundreds of potentially Earthlike planets as they pass in front of their host stars. These and other future telescopes aim to provide more sensitive studies of more alien worlds. Their development prompts two important questions: 'Where to look?' and 'Are the environments where we think we see signs of life actually habitable?' The strongly disputed claims of potential signs of life in the exoplanet K2-18b, announced in April 2025, and previous similar claims in Venus, show how difficult it is to conclusively identify the presence of life from remote-sensing data. Oxford Languages defines 'habitable' as 'suitable or good enough to live in.' But how do scientists know what is 'good enough to live in' for extraterrestrial organisms? Could alien microbes frolic in lakes of boiling acid or frigid liquid methane, or float in water droplets in Venus' upper atmosphere? To keep it simple, NASA's mantra has been 'follow the water.' This makes sense – water is essential for all Earth life we know of. A planet with liquid water would also have a temperate environment. It wouldn't be so cold that it slows down chemical reactions, nor would it be so hot that it destroys the complex molecules necessary for life. However, with astronomers' rapidly growing capabilities for characterizing alien worlds, astrobiologists need an approach that is more quantitative and nuanced than the water or no-water classification. As part of the NASA-funded Alien Earths project that I lead, astrobiologist Rory Barnes and I worked on this problem with a group of experts – astrobiologists, planetary scientists, exoplanet experts, ecologists, biologists and chemists – drawn from the largest network of exoplanet and astrobiology researchers, NASA's Nexus for Exoplanet System Science, or NExSS. Over a hundred colleagues provided us with ideas, and two questions came up often: First, how do we know what life needs, if we do not understand the full range of extraterrestrial life? Scientists know a lot about life on Earth, but most astrobiologists agree that more exotic types of life – perhaps based on different combinations of chemical elements and solvents – are possible. How do we determine what conditions those other types of life may require? Second, the approach has to work with incomplete data. Potential sites for life beyond Earth – 'extrasolar habitats' – are very difficult to study directly, and often impossible to visit and sample. For example, the Martian subsurface remains mostly out of our reach. Places like Jupiter's moon Europa's and Saturn's Moon Enceladus' subsurface oceans and all extrasolar planets remain practically unreachable. Scientists study them indirectly, often only using remote observations. These measurements can't tell you as much as actual samples would. To make matters worse, measurements often have uncertainties. For example, we may be only 88% confident that water vapor is present in an exoplanet's atmosphere. Our framework has to be able to work with small amounts of data and handle uncertainties. And, we need to accept that the answers will often not be black or white. The new approach, called the quantitative habitability framework, has two distinguishing features: First, we moved away from trying to answer the vague 'habitable to life' question and narrowed it to a more specific and practically answerable question: Would the conditions in the habitat – as we know them – allow a specific (known or yet unknown) species or ecosystem to survive? Even on Earth, organisms require different conditions to survive – there are no camels in Antarctica. By talking about specific organisms, we made the question easier to answer. Second, the quantitative habitability framework does not insist on black-or-white answers. It compares computer models to calculate a probabilistic answer. Instead of assuming that liquid water is a key limiting factor, we compare our understanding of the conditions an organism requires (the 'organism model') with our understanding of the conditions present in the environment (the 'habitat model'). Both have uncertainties. Our understanding of each can be incomplete. Yet, we can handle the uncertainties mathematically. By comparing the two models, we can determine the probability that an organism and a habitat are compatible. As a simplistic example, our habitat model for Antarctica may state that temperatures are often below freezing. And our organism model for a camel may state that it does not survive long in cold temperatures. Unsurprisingly, we would correctly predict a near-zero probability that Antarctica is a good habitat for camels. We had a blast working on this project. To study the limits of life, we collected literature data on extreme organisms, from insects that live in the Himalayas at high altitudes and low temperatures to microorganisms that flourish in hydrothermal vents on the ocean floor and feed on chemical energy. We explored, via our models, whether they may survive in the Martian subsurface or in Europa's oceans. We also investigated if marine bacteria that produce oxygen in Earth's oceans could potentially survive on known extrasolar planets. Although comprehensive and detailed, this approach makes important simplifications. For example, it does not yet model how life may shape the planet, nor does it account for the full array of nutrients organisms may need. These simplifications are by design. In most of the environments we currently study, we know too little about the conditions to meaningfully attempt such models – except for some solar system bodies, such as Saturn's Enceladus. The quantitative habitability framework allows my team to answer questions like whether astrobiologists might be interested in a subsurface location on Mars, given the available data, or whether astronomers should turn their telescopes to planet A or planet B while searching for life. Our framework is available as an open-source computer model, which astrobiologists can now readily use and further develop to help with current and future projects. If scientists do detect a potential signature of life, this approach can help assess if the environment where it is detected can actually support the type of life that leads to the signature detected. Our next steps will be to build a database of terrestrial organisms that live in extreme environments and represent the limits of life. To this data, we can also add models for hypothetical alien life. By integrating those into the quantitative habitability framework, we will be able to work out scenarios, interpret new data coming from other worlds and guide the search for signatures of life beyond Earth – in our solar system and beyond. This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world. It was written by: Daniel Apai, University of Arizona Read more: Are we alone in the universe? 4 essential reads on potential contact with aliens 'Extraordinary claims require extraordinary evidence' − an astronomer explains how much evidence scientists need to claim discoveries like extraterrestrial life Extraterrestrial life may look nothing like life on Earth − so astrobiologists are coming up with a framework to study how complex systems evolve Daniel Apai receives funding from NASA, Heising-Simons Foundation, Department of Defense, Space Telescope Science Institute, and the University of Arizona, and leads the NASA-funded Alien Earths astrobiology research team that developed the framework described here. He is affiliated with the Steward Observatory and Lunar and Planetary Laboratory of The University of Arizona.
Yahoo
22-02-2025
- Science
- Yahoo
What's that smell? Astronomers discover a stinky new clue in the search for alien life
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have discovered that sulfur may be a key to helping us narrow down our search for life on other planets. It's not that sulfur is a great indication that a planet is inhabited. Instead, it's the opposite: Significant amounts of sulfur dioxide in a planet's atmosphere is a good sign that the world is uninhabitable and we can safely cross it off the list of candidates. One of the holy grails of modern astronomy is finding life on an alien planet. But that is an extremely daunting task. The James Webb Space Telescope is unlikely to be able to identify biosignatures — the atmospheric gases produced by life — in any nearby worlds. And the upcoming Habitable Worlds Observatory will be able to scan only a few dozen potentially habitable exoplanets. One of the big hurdles is that biosignature spectra are usually very weak. So one way to narrow down the list of potential candidates is to focus on the ability of a planet to host life, mainly in the form of water vapor in its atmosphere. If a planet has a lot of water vapor, it might have a good chance of hosting life as well. This requirement is the basis of the habitable zone, the region around a star where the radiation onto a planet isn't too little that all the water freezes out and isn't too much that the water boils away. In our solar system, Venus is near the inner edge of the habitable zone, and its surface reaches temperatures of over 800 degrees Fahrenheit (427 degrees Celsius) underneath a thick, choking atmosphere. On the opposite end, Mars is essentially frozen out, with all of its water locked up in polar ice caps and under the surface. But even a search for water has difficulties. For example, from great distances, it's very difficult to tell Earth (inhabited) apart from Venus (uninhabited and outright hostile to life). Their atmospheric spectra are just too similar when you're trying to hunt for water vapor. In a recent preprint paper, astronomers note that they've found a different signature gas that might be a useful tool for separating uninhabitable worlds from potentially habitable ones: sulfur dioxide. Warm, wet worlds like Earth have very little sulfur dioxide in their atmospheres. That's because rain can pick up atmospheric sulfur dioxide and wash it down into the oceans or into the soil, essentially cleansing it out of the atmosphere. And, ironically, planets like Venus also have very little sulfur dioxide. In that planet's case, high amounts of ultraviolet radiation from the sun catalyze reactions that convert sulfur dioxide to hydrogen sulfide in the upper atmosphere. There's still a lot of sulfur dioxide, but it tends to slink down into the lower atmosphere, where it can't be detected. Thankfully, there's another option: planets around red dwarf stars. Red dwarfs emit very little ultraviolet radiation. So if a dry, uninhabitable planet were to form around a star like that, a lot of sulfur dioxide would persist in its upper atmosphere. Astronomers are especially interested in the planetary systems of red dwarfs. One reason is that red dwarfs are the most common kind of star in the galaxy. The other is that many nearby systems — like our nearest neighbor, Proxima Centauri, as well as TRAPPIST-1 — are red dwarfs known to host planets. This makes them very appealing targets for upcoming searches for life. Related stories: —What really makes a planet habitable? Our assumptions may be wrong —We don't really understand the habitable zones of alien planets —The 10 most Earth-like exoplanets The new technique based on sulfur dioxide can't tell us which planets might host life, but they do tell us which planets probably don't. If we see a rocky planet orbiting a red dwarf and detect an abundance of sulfur dioxide in its atmosphere, it is likely a lot like Venus — a dry, hot world with a thick atmosphere and little to no water. Not a good candidate for life. But if we fail to see any significant sulfur dioxide, that world is likely a good candidate for a follow-up observation to search for signs of water vapor and, if we're lucky, life. It's going to take an enormous amount of detective work and dogged determination to find life on another planet. So any clue we can get, even one based on sulfur dioxide to narrow down our list, is welcome.
Yahoo
22-02-2025
- Science
- Yahoo
What's that smell? Astronomers discover a stinky new clue in the search for alien life
When you buy through links on our articles, Future and its syndication partners may earn a commission. Astronomers have discovered that sulfur may be a key to helping us narrow down our search for life on other planets. It's not that sulfur is a great indication that a planet is inhabited. Instead, it's the opposite: Significant amounts of sulfur dioxide in a planet's atmosphere is a good sign that the world is uninhabitable and we can safely cross it off the list of candidates. One of the holy grails of modern astronomy is finding life on an alien planet. But that is an extremely daunting task. The James Webb Space Telescope is unlikely to be able to identify biosignatures — the atmospheric gases produced by life — in any nearby worlds. And the upcoming Habitable Worlds Observatory will be able to scan only a few dozen potentially habitable exoplanets. One of the big hurdles is that biosignature spectra are usually very weak. So one way to narrow down the list of potential candidates is to focus on the ability of a planet to host life, mainly in the form of water vapor in its atmosphere. If a planet has a lot of water vapor, it might have a good chance of hosting life as well. This requirement is the basis of the habitable zone, the region around a star where the radiation onto a planet isn't too little that all the water freezes out and isn't too much that the water boils away. In our solar system, Venus is near the inner edge of the habitable zone, and its surface reaches temperatures of over 800 degrees Fahrenheit (427 degrees Celsius) underneath a thick, choking atmosphere. On the opposite end, Mars is essentially frozen out, with all of its water locked up in polar ice caps and under the surface. But even a search for water has difficulties. For example, from great distances, it's very difficult to tell Earth (inhabited) apart from Venus (uninhabited and outright hostile to life). Their atmospheric spectra are just too similar when you're trying to hunt for water vapor. In a recent preprint paper, astronomers note that they've found a different signature gas that might be a useful tool for separating uninhabitable worlds from potentially habitable ones: sulfur dioxide. Warm, wet worlds like Earth have very little sulfur dioxide in their atmospheres. That's because rain can pick up atmospheric sulfur dioxide and wash it down into the oceans or into the soil, essentially cleansing it out of the atmosphere. And, ironically, planets like Venus also have very little sulfur dioxide. In that planet's case, high amounts of ultraviolet radiation from the sun catalyze reactions that convert sulfur dioxide to hydrogen sulfide in the upper atmosphere. There's still a lot of sulfur dioxide, but it tends to slink down into the lower atmosphere, where it can't be detected. Thankfully, there's another option: planets around red dwarf stars. Red dwarfs emit very little ultraviolet radiation. So if a dry, uninhabitable planet were to form around a star like that, a lot of sulfur dioxide would persist in its upper atmosphere. Astronomers are especially interested in the planetary systems of red dwarfs. One reason is that red dwarfs are the most common kind of star in the galaxy. The other is that many nearby systems — like our nearest neighbor, Proxima Centauri, as well as TRAPPIST-1 — are red dwarfs known to host planets. This makes them very appealing targets for upcoming searches for life. Related stories: —What really makes a planet habitable? Our assumptions may be wrong —We don't really understand the habitable zones of alien planets —The 10 most Earth-like exoplanets The new technique based on sulfur dioxide can't tell us which planets might host life, but they do tell us which planets probably don't. If we see a rocky planet orbiting a red dwarf and detect an abundance of sulfur dioxide in its atmosphere, it is likely a lot like Venus — a dry, hot world with a thick atmosphere and little to no water. Not a good candidate for life. But if we fail to see any significant sulfur dioxide, that world is likely a good candidate for a follow-up observation to search for signs of water vapor and, if we're lucky, life. It's going to take an enormous amount of detective work and dogged determination to find life on another planet. So any clue we can get, even one based on sulfur dioxide to narrow down our list, is welcome.
