Space and astronomy news
The Daisy World model describes a hypothetical planet that self-regulates, maintaining a delicate balance involving its biogeochemical cycles, climate, and feedback loops that keep it habitable. It’s associated with the Gaia Hypothesis developed by James Lovelock. How can we detect these worlds if they’re out there?
By looking closely at information.
Continue reading “A New Way to Detect Daisy Worlds”
Earth is the only life-supporting planet we know of, so it’s tempting to use it as a standard in the search for life elsewhere. But the modern Earth can’t serve as a basis for evaluating exoplanets and their potential to support life. Earth’s atmosphere has changed radically over its 4.5 billion years.
A better way is to determine what biomarkers were present in Earth’s atmosphere at different stages in its evolution and judge other planets on that basis.
Continue reading “What Can Early Earth Teach Us About the Search for Life?”
The JWST is astronomers’ best tool for probing exoplanet atmospheres. Its capable instruments can dissect the light passing through a distant world’s atmosphere and determine its chemical components. Scientists are interested in everything the JWST finds, but when it finds something indicating the possibility of life it seizes everyone’s attention.
That’s what happened in September 2023, when the JWST found dimethyl sulphide (DMS) in the atmosphere of the exoplanet K2-18b.
Continue reading “Did You Hear Webb Found Life on an Exoplanet? Not so Fast…”
If we could detect a clear, unambiguous biosignature on just one of the thousands of exoplanets we know of, it would be a huge, game-changing moment for humanity. But it’s extremely difficult. We simply aren’t in a place where we can be certain that what we’re detecting means what we think or even hope it does.
But what if we looked at many potential worlds at once?
Continue reading “Life Might Be Difficult to Find on a Single Planet But Obvious Across Many Worlds”
Discovering exoplanets is almost routine now. We’ve found over 5,500 exoplanets, and the next step is to study their atmospheres and look for biosignatures. The James Webb Space Telescope is leading the way in that effort. But in some exoplanet atmospheres, lightning could make the JWST’s job more difficult by obscuring some potential biosignatures while amplifying others.
Continue reading “If Exoplanets Have Lightning, it’ll Complicate the Search for Life”
There are more than 5,000 confirmed exoplanets in our galaxy. That number is going to rise significantly in the next decade. The Transiting Exoplanet Survey Satellite (TESS) has already cataloged more than 4,000 candidate exoplanets, and the PLAnetary Transits and Oscillations of stars (PLATO) is scheduled to launch in 2026. We will soon have more than 10,000 worlds where life might be able to survive. It’s an amazing idea, but with so many exoplanets we don’t have the resources to search for life on all of them. So how do we prioritize our search?
Continue reading “TESS Has Found Thousands of Possible Exoplanets. Which Ones Should JWST Study?”
When it comes to looking for extraterrestrial life “out there” astronomers scan distant planets. They also look for technosignatures at alien worlds. What if the answer they seek is dust blowing on the interstellar winds?
Continue reading “Are We Alone? The Answer Might Be in Space Dust That’s All Around Us”
Less than a year after it went to space, the James Webb Space Telescope (JWST) has already demonstrated its worth many times over. The images it has acquired of distant galaxies, nebulae, exoplanet atmospheres, and deep fields are the most detailed and sensitive ever taken. And yet, one of the most exciting aspects of its mission is just getting started: the search for evidence of life beyond Earth. This will consist of Webb using its powerful infrared instruments to look for chemical signatures associated with life and biological processes (aka. biosignatures).
The chemical signatures vary, each representing a different pathway toward the potential discovery of life. According to The Conversation’s Joanna Barstow, a planetary scientist and an Ernest Rutherford Fellow at The Open University specializing in the study of exoplanet atmospheres, there are four ways that Webb could do this. These include looking for chemicals that lifeforms depend on, chemical byproducts produced by living organisms, chemicals essential to maintaining a stable climate, and chemicals that shouldn’t coexist.
Continue reading “Here are Four Ways JWST Could Detect Alien Life”
Here is an idea that likely never crossed the mind of most space enthusiasts – a gas emitted from broccoli (and other plants) is one of the most indicative signs of the existence of life on a planet. At least according to a new study from researchers at the University of California Riverside.
Continue reading “If we Detect This gas on Other Planets, it’s a Good Sign There’s Life There”
One of the most exciting aspects of space exploration today is how the field of astrobiology – the search for life in our Universe – has become so prominent. In the coming years, many robotic and even crewed missions will be bound for Mars that will aid in the ongoing search for life there. Beyond Mars, missions are planned for the outer Solar System that will explore satellites and bodies with icy exteriors and interior oceans – otherwise known as “Ocean Worlds.” These include the Jovian satellites Europa and Ganymede and Saturn’s moons Titan and Enceladus.
Similar to how missions to Mars have analyzed soil and rock samples for evidence of past life, the proposed missions will analyze liquid samples for the chemical signatures that we associate with life and biological processes (aka. “biosignatures”). To aid in this search, scientists at NASA’s Jet Propulsion Laboratory have designed the Ocean Worlds Life Surveyor (OWLS), a suite of eight scientific instruments designed to sniff out biosignatures. In the coming decades, this suite could be used by robotic probes bound for “Ocean Worlds” all across the Solar System to search for signs of life.
Continue reading “NASA has Built a Collection of Instruments That Will Search for Life Inside Europa and Enceladus”