Life Archives

March 10, 2024March 10, 2024 by Carolyn Collins Petersen

Cyborg Jellyfish Could Help Explore Oceans Autonomously

A scene from a video about cyborg jellyfish created at Caltech. Courtesy Jahn Dabiri

Earth’s oceans are—like space—a largely unexplored frontier. Relatively few humans have explored either place, using specialized life-support equipment. Unlike space, however, the oceans also have other beings that can explore them: jellyfish. They can head to places underwater that humans can never go. That makes them interesting candidates for autonomous ocean exploration.

March 5, 2024March 5, 2024 by Evan Gough

Juno Measures How Much Oxygen is Being Produced by Europa

This view of Jupiter’s icy moon Europa was captured by the JunoCam imager aboard NASA’s Juno spacecraft during the mission’s close flyby on Sept. 29, 2022. Image data: NASA/JPL-Caltech/SwRI/MSSS Image processing: Kevin M. Gill CC BY 3.0

If the periodic table listed the elements in order of their importance to life, then oxygen might bully its way to the top. Without oxygen, Earth’s complex life likely would not exist. So when scientists detect oxygen on another world, they turn their attention to it.

February 24, 2024February 24, 2024 by Brian Koberlein

Cosmic Dust Could Have Helped Get Life Going on Earth

This artist’s impression shows dust forming in the environment around a supernova explosion. Credit: ESO/M. Kornmesser

Life on our planet appeared early in Earth’s history. Surprisingly early, since in its early youth our planet didn’t have much of the chemical ingredients necessary for life to evolve. Since prebiotic chemicals such as sugars and amino acids are known to appear in asteroids and comets, one idea is that Earth was seeded with the building blocks of life by early cometary and asteroid impacts. While this likely played a role, a new study shows that cosmic dust also seeded young Earth, and it may have made all the difference.

February 13, 2024February 13, 2024 by Evan Gough

Dying Stars Could Have Completely New Habitable Zones

As stars like our Sun age, their habitable zones shift, and they can warm planets that were once frozen. Image Credit: ESO/L. Calçada

Aging stars that become red giants increase their luminosity and can wreak havoc on planets that were once in the star’s habitable zones. When the Sun becomes a red giant and expands, its habitable zone will move further outward, meaning Earth will likely lose its atmosphere, its water, and its life. But for planets further out, their time in the habitable zone will just begin.

Is there enough time for life to arise on these newly habitable planets?

February 13, 2024February 13, 2024 by Evan Gough

Cosmic Dust Could Spread Life from World to World Across the Galaxy

Could life spread throughout the galaxy on tiny grains of dust? It would be a perilous journey, but new research shows its possible and calculates how long it would take to spread. Image Credit: ESO

Does life appear independently on different planets in the galaxy? Or does it spread from world to world? Or does it do both?

New research shows how life could spread via a basic, simple pathway: cosmic dust.

February 12, 2024February 12, 2024 by Mark Thompson

Could We Live Without Kilonovae?

It’s a classic statement shared at many public outreach events…’we are made of stardust’. It is true enough that the human body is mostly water with some other elelments like carbon which are formed inside stars just like the Sun. It’s not just common elements like carbon though for we also have slighly more rare elements like iodine and bromine. They don’t form in normal stars but instead are generated in collisions between neutron stars! It poses an interesting question, without the neutron star merger event; ‘would we exist?’

January 30, 2024January 23, 2024 by Paul M. Sutter

The Seeming Impossibility of Life

This is an artist's illustration showing the timeline of the early universe showing some key time periods. On the left is the early day of the Universe, where the intense heat prevented much from happening. After that is the release of the CMB once the Universe cooled a little. After that, in yellow, is the Neutral Universe, the time before stars formed. The hydrogen atoms in the Neutral Universe should have given off radio waves that we can detect here on Earth. Image Credit: ESA – C. Carreau — This is an artist's illustration showing the timeline of the early universe showing some key time periods. On the left is the early day of the Universe, where the intense heat prevented much from happening. After that is the release of the CMB once the Universe cooled a little. After that, in yellow, is the neutral Universe, the time before stars formed. The hydrogen atoms in the neutral Universe should have given off radio waves that we can detect here on Earth. Image Credit: ESA – C. Carreau

The number of near misses, false starts, and legitimate disasters that have befallen our species since the day we took our first upright steps all those generations ago is too large to count and could honestly take up this entire book. I’ll give us humans this much, though: we’re survivors, through and through.

January 28, 2024January 23, 2024 by Paul M. Sutter

The Improbable Origins of Life on Earth

We do not yet know how, where, or why life first appeared on our planet. Part of the difficulty is that “life” has no strict, universally agreed-upon definition.

January 26, 2024January 23, 2024 by Paul M. Sutter

Early Life Was Radically Different Than Today

Hydrothermal vents deep in Earth's oceans. Could similar types of vents power the transport of silica and other materials out from Enceladus? Credit: NOAA

All modern life shares a robust, hardy, efficient system of intertwined chemicals that propagate themselves. This system must have emerged from a simpler, less efficient, more delicate one. But what was that system, and why did it appear on, of all places, planet Earth?

January 21, 2024January 21, 2024 by Brian Koberlein

The Next Generation LIFE Telescope Could Detect Some Intriguing Biosignatures

Artist's impression of the proposed LIFE mission. Credit: LIFE Initiative / ETH Zurich

The Large Interferometer for Exoplanets (LIFE) project is an ambitious plan to build a space telescope with four independent mirrors. The array would allow the individual mirrors to move closer or farther apart, similar to the way the Very Large Array (VLA) does with radio antennas. LIFE is still early in its planning stage, so it would likely be decades before it is built, but already the LIFE team is looking at ways it might discover life on other worlds. Much of this focuses on the detection of biogenic molecules in exoplanet atmospheres.