Space and astronomy news
Astronomers have spotted barium in the atmosphere of a distant exoplanet. With its 56 protons, you have to run your finger further down the periodic table than astronomers usually do to find barium. What does finding such a heavy element in an exoplanet atmosphere mean?
It means we’re still learning how strange exoplanets can be.
Continue reading “The Heaviest Element Ever Seen in an Exoplanet’s Atmosphere: Barium”
Finding oxygen in an exoplanet’s atmosphere is a clue that life may be at work. On Earth, photosynthetic organisms absorb carbon dioxide, sunlight, and water and produce sugars and starches for energy. Oxygen is the byproduct of that process, so if we can detect oxygen elsewhere, it’ll generate excitement. But researchers have also put pressure on the idea that oxygen in an exoplanet’s atmosphere indicates life. It’s only evidence of life if we can rule out other pathways that created the oxygen.
But scientists can’t rule them out.
Continue reading “Scientists Discover a New Way Exoplanets Could Make Oxygen; Unfortunately, it Doesn’t Require Life”
When the James Webb Space Telescope aims at exoplanet atmospheres, it’ll use spectroscopy to identify chemical elements. One of the things it’s looking for is methane, a chemical compound that can indicate the presence of life.
Methane is a compelling biosignature. Finding a large amount of methane in an exoplanet’s atmosphere might be our most reliable indication that life’s at work there. There are abiotic sources of methane, but for the most part, methane comes from life.
But to understand methane as a potential biosignature, we need to understand it in a planetary context. A new research letter aims to do that.
Continue reading “It’s Not Conclusive, But Methane is Probably the Best Sign of Life on Exoplanets”
Earth formed over 4.5 billion years ago via accretion. Earth’s building blocks were chunks of rock of varying sizes. From dust to planetesimals and everything in between. Many of those chunks of rock were carbonaceous meteorites, which scientists think came from asteroids in the outer reaches of the main asteroid belt.
But some evidence doesn’t line up well behind that conclusion. A new study says that some of the Earth-forming meteorites came from much further out in the Solar System.
Continue reading “The Building Blocks of Earth Could Have Come From Farther out in the Solar System”
Will we ever understand life’s origins? Will we ever be able to put our finger on the exact moment and circumstances that lead to living matter? Will we ever pinpoint the spark? Who knows.
But what we can do is find out how widespread the conditions for life are and how widespread the molecular constituents for life are.
Continue reading “Even More Complex Organic Molecules Have Been Found in a Protoplanetary Disc. Was Life Inevitable?”
We know a ton about the inside of Earth. We know it has both an inner core and an outer core and that the churning and rotation create a protective magnetosphere that shields life from the Sun’s radiative power. It has a mantle, primarily solid but also home to magma. We know it has a crust, where we live, and plate tectonics that moves the continents around like playthings.
But what about Super-Earths? We know they’re out there; we’ve found them. What do we know about their insides? Earth’s structure, and its ability to support life, are shaped by the extreme pressure and density in its interior. The pressure and temperature inside Super-Earths are even more powerful. How does it shape these planets and affect their habitability?
Continue reading “What’s it Like Inside a Super-Earth?”
Peptides are one of the smallest biomolecules and are one of life’s critical building blocks. New research shows that they could form on the surfaces of icy grains in space. This discovery lends credence to the idea that meteoroids, asteroids, or comets could have given life on Earth a kick start by crashing into the planet and delivering biological building blocks.
Continue reading “One of Life’s Building Blocks can Form in Space”
Carbon is critical to life, as far as we know. So anytime we detect a strong carbon signature somewhere like Mars, it could indicate biological activity.
Does a strong carbon signal in Martian rocks indicate biological processes of some type?
Continue reading “Curiosity Sees a Strong Carbon Signature in a Bed of Rocks”
Without phosphorus, there’s no life. It’s a necessary part of DNA, RNA, and other biological molecules like ATP, which helps cells transport energy. But any phosphorus that was present when Earth formed would’ve been sequestered in the center of the molten planet.
So where did phosphorus come from?
It might have come from cosmic dust.
Continue reading “Did Cosmic Dust Deliver the Phosphorus Needed for Life?”
Author’s note – this article was written with Dr. Vincent Kofman, a scientist at NASA’s Goddard Space Flight Center (GSFC), working in the Sellers Exoplanet Environments Collaboration (SEEC), and the lead author on the research it discusses.
Thousands of exoplanets have been discovered in the recent decades. Planet hunters like TESS and Kepler, as well as numerous ground-based efforts, have pushed the field and we are starting to get a total number of planets that will allow us to perform effective statistical analysis on some of them.
Not only do the detected number of planets show us how common they are; it exposes our lack of understanding about how planets form, what conditions are present, and when planets may be habitable. The transit detection of an exoplanet primarily yields the orbital period, or the length of a year on the planet, and the relative size of the planet with respect to the star. The next steps are to characterize the planet. This usually requires follow up studies, using different observational strategies and more powerful telescopes.
Continue reading “How To Search the Chemical Makeup of Exoplanet Atmospheres for Hints at Their History”