Lifeboat Foundation

For decades, science fiction authors have imagined scenarios in which life thrives on the harsh surfaces of Mars or our moon, or in the oceans below the icy surfaces of Saturn’s moon Enceladus and Jupiter’s moon Europa. But the study of habitability—the conditions required to support and sustain life—is not just confined to the pages of fiction. As more planetary bodies in our solar system and beyond are investigated for their potential to host conditions favorable to life, researchers are debating how to characterize habitability.

While many studies have focused on the information obtained by orbiting spacecraft or telescopes that provide snapshot views of ocean worlds and exoplanets, a new paper emphasizes the importance of investigating complex geophysical factors that can be used to predict the long-term maintenance of life. These factors include how energy and nutrients flow throughout the planet.

“Time is a crucial factor in characterizing habitability,” says Mark Simons, John W. and Herberta M. Miles Professor of Geophysics at Caltech. “You need time for evolution to happen. To be habitable for a millisecond or a year is not enough. But if habitable conditions are sustained for a million years, or a billion…? Understanding a planet’s habitability takes a nuanced perspective that requires astrobiologists and geophysicists to talk to each other.”

“We think that the HD 144,432 disk may be very similar to the early Solar System that provided lots of iron to the rocky planets we know today,” said Dr. Roy van Boekel.

How did our solar system form and is this process similar in other solar systems throughout the universe? This is what a study published today in Astronomy & Astrophysics hopes to figure out as a team of international researchers used data from the European Southern Observatory’s (ESO) Very Large Telescope Interferometer (VLTI) to analyze the protoplanetary disk around HD 144,432, which is a young star located approximately 500 light-years from Earth. This study holds the potential to not only help researchers better understand the formation and evolution of solar systems, but also gain greater insight into how life could evolve in these systems, as well.

“When studying the dust distribution in the disk’s innermost region, we detected for the first time a complex structure in which dust piles up in three concentric rings in such an environment,” said Dr. Roy van Boekel, who is a scientist at the Max Planck Institute for Astronomy (MPIA) and one of more than three dozen co-authors on the study. “That region corresponds to the zone where the rocky planets formed in the Solar System.”

Continue reading “Complex Ring System Around Young Star Resembles Early Solar System Formation” »

A low carbon abundance in planetary atmospheres could be a signature of habitability. Scientists at MIT, the University of Birmingham, and elsewhere say that astronomers’ best chance of finding liquid water, and even life on other planets, is to look for the absence, rather than the presence, of a chemical feature in their atmospheres.

The researchers propose that if a terrestrial planet has substantially less CO₂ in its atmosphere compared to other planets in the same system, it could be a sign of liquid water — and possibly life — on that planet’s surface.

What’s more, this new signature is within the sights of NASA’s James Webb Space Telescope (JWST). While scientists have proposed other signs of habitability, those features are challenging if not impossible to measure with current technologies. The team says this new signature, of relatively depleted carbon dioxide, is the only sign of habitability that is detectable now.

Darwin applied the theory of evolution to life on earth, but not to other massively complex systems like planets, stars, atoms and minerals. Now, an interdisciplinary group of researchers has identified a missing aspect of that theory that applies to essentially everything.

Their paper, “On the roles of function and selection in evolving systems,” published Oct. 16 in the Proceedings of the National Academy of Sciences, describes “a missing law of nature” that recognizes for the first time an important norm within the natural world’s workings. The new law states that complex natural systems evolve to states of greater patterning, diversity and complexity.

“This was a true collaboration between scientists and philosophers to address one of the most profound mysteries of the cosmos: why do complex systems, including life, evolve toward greater functional information over time?” said co-author Jonathan Lunine, the David C. Duncan Professor in the Physical Sciences and chair of astronomy in the College of Arts and Sciences.

“The Holy Grail in exoplanet science is to look for habitable worlds and the presence of life, but all the features that have been talked about so far have been beyond the reach of the newest observatories,” Julien de Wit, discovery team member and an assistant professor of planetary sciences at MIT, said in a statement. “Now we have a way to find out if there’s liquid water on another planet. And it’s something we can get to in the next few years.”

Currently, scientists are very good at using instruments to determine how far a planet is from its host star and thus whether it is in that star’s “habitable zone” — defined as the region that’s neither too hot nor too cold to allow for the existence of liquid water.

In our own solar system, however, Earth, Mars and even Venus are all in the habitable zone around the sun. Yet, only one of those planets currently has the capability to support life as we know it. That means habitability and preserving liquid water for exoplanets isn’t all location, location, location. So, currently, scientists don’t have a robust way of confirming if a planet is habitable or not.

University of Rochester astrophysicist Adam Frank explores the links between atmospheric oxygen and detecting extraterrestrial technology on distant planets.

In the quest to understand the potential for life beyond Earth, researchers are widening their search to encompass not only biological markers, but also technological ones. While astrobiologists have long recognized the importance of oxygen for life as we know it, oxygen could also be a key to unlocking advanced technology on a planetary scale.

In a new study published in Nature Astronomy, Adam Frank, the Helen F. and Fred H. Gowen Professor of Physics and Astronomy at the University of Rochester and the author of The Little Book of Aliens (Harper, 2023), and Amedeo Balbi, an associate professor of astronomy and astrophysics at the University of Roma Tor Vergata, Italy, outline the links between atmospheric oxygen and the potential rise of advanced technology on distant planets.

An AI trained to hunt for technosignatures from intelligent alien life found 8 interesting signals on its first deployment.

Can a lack of certain atmospheric characteristics in an exoplanet be a sign of life? This is what a team of international scientists hope to unlock as they discuss a novel strategy for detecting the lack of carbon dioxide in a rocky exoplanet’s atmosphere compared to other planets in the same system and how it could help isolate where to look for life. In a recent study published in Nature Astronomy, the researchers ascertain this investigation could be conducted using data from NASA’s James Webb Space Telescope (JWST) and holds the potential to help astronomers better understand the necessary atmospheric conditions that could be suitable for finding life as we know it throughout the cosmos.

“The Holy Grail in exoplanet science is to look for habitable worlds, and the presence of life, but all the features that have been talked about so far have been beyond the reach of the newest observatories,” said Dr. Julien de Wit, who is an assistant professor of planetary sciences at the Massachusetts Institute of Technology and a co-author on the study. “Now we have a way to find out if there’s liquid water on another planet. And it’s something we can get to in the next few years.”

The researchers postulate a three-step strategy for using JWST in detecting carbon dioxide and ozone in exoplanets residing in the TRAPPIST-1 system located approximately 40 light-years from Earth. This strategy calls for detecting a planetary atmosphere around rocky exoplanets in approximately 10 transits of the parent star, assessing a lack of carbon dioxide within the exoplanet’s atmosphere in approximately 40 transits, and obtaining measurements of the atmosphere’s ozone while comparing this to the lack of carbon dioxide in approximately 100 transits.

The absence, not the presence, of the most important element for life in planets’ atmospheres may be what we should be seeking.