Measuring the Atmospheres of Other Worlds to See if There are Enough Nutrients for Life

A NASA graphic explaining how a telescope can measure an exoplanet atmosphere using spectroscopy. Courtesy: NASA/JPL-Caltech/Lizbeth B. De La Torre.
A NASA graphic explaining how a telescope can measure an exoplanet atmosphere using spectroscopy. Courtesy: NASA/JPL-Caltech/Lizbeth B. De La Torre.

Life on Earth depends on six critical elements: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, and Sulfur. These elements are referred to as CHNOPS, and along with several trace micronutrients and liquid water, they’re what life needs.

Scientists are getting a handle on detecting exoplanets that might be warm enough to have liquid water on their surfaces, habitability’s most basic signal. But now, they’re looking to up their game by finding CHNOPS in exoplanet atmospheres.

Continue reading “Measuring the Atmospheres of Other Worlds to See if There are Enough Nutrients for Life”

Can the Gaia Hypothesis Be Tested in the Lab?

A new paper proposes an experimental setup that could test the classic Daisyworld model — a hypothesis of a self-regulating planetary ecosystem — in the lab via two synthetic bacterial strains. Credit: Victor Maull/Image Designer

During the 1970s, inventor/environmentalist James Lovelock and evolutionary biologist Lynn Margulis proposed the Gaia Hypothesis. This theory posits that Earth is a single, self-regulating system where the atmosphere, hydrosphere, all life, and their inorganic surroundings work together to maintain the conditions for life on the planet. This theory was largely inspired by Lovelock’s work with NASA during the 1960s, where the skilled inventor designed instruments for modeling the climate of Mars and other planets in the Solar System.

According to this theory, planets like Earth would slowly grow warmer and their oceans more acidic without a biosphere that regulates temperature and ensures climate stability. While the theory was readily accepted among environmentalists and climatologists, many in the scientific community have remained skeptical since it was proposed. Until now, it has been impossible to test this theory because it involves forces that work on a planetary scale. But in a recent paper, a team of Spanish scientists proposed an experimental system incorporating synthetic biology that could test the theory on a small scale.

Continue reading “Can the Gaia Hypothesis Be Tested in the Lab?”

Could We Find Aliens Terraforming Other Worlds?

Artist's conception of a terraformed Mars. Credit: Ittiz/Wikimedia Commons

The first early humans to use fire had no inkling of what it would lead to.

Fire was one of our first technologies, and humans have been making changes to their environments since the advent of controlled fire hundreds of thousands of years ago. Fast forward to current times, and our modern technological and global civilization is changing the Earth’s entire biosphere. From carbon emissions that acidify the oceans and weaken the shells of marine life to microplastics that find their way into organisms’ bloodstreams, our technology is intersecting, or combining, with the biosphere.

This has spawned a useful word: biotechnosphere.

Continue reading “Could We Find Aliens Terraforming Other Worlds?”

Does the Entire Planet Have a Mind of its Own?

In a self-described "thought experiment," University of Rochester astrophysicist Adam Frank and colleagues David Grinspoon at the Planetary Science Institute and Sara Walker at Arizona State University use scientific theory and broader questions about how life alters a planet, to posit four stages to describe Earth's past and possible future. Image Credit: (University of Rochester illustration / Michael Osadciw)

What is humanity? Do our minds set us apart from the rest of nature and from the rest of Earth? Or does Earth have a collective mind of its own, and we’re simply part of that mind? On the literal face of it, that last question might sound ridiculous.

But a new thought experiment explores it more deeply, and while there’s no firm conclusion about humanity and a planetary mind, just thinking about it invites minds to reconsider their relationship with nature.

Overcoming our challenges requires a better understanding of ourselves and nature, and the same is true for any other civilizations that make it past the Great Filter.

Continue reading “Does the Entire Planet Have a Mind of its Own?”

New Data Show How Phytoplankton Pumps Carbon Out of the Atmosphere at an Enormous Scale

One of the most fascinating things about planet Earth is the way that life shapes the Earth and the Earth shapes life. We only have to look back to the Great Oxygenation Event (GOE) of 2.4 billion years ago to see how lifeforms have shaped the Earth. In that event, phytoplanktons called cyanobacteria pumped the atmosphere with oxygen, extinguishing most life on Earth, and paving the way for the development of multicellular life.

Early Earth satisfied the initial conditions for life to appear, and now, lifeforms shape the atmosphere, the landscape, and the oceans in many different ways.

At the base of many of these changes is phytoplankton.

Continue reading “New Data Show How Phytoplankton Pumps Carbon Out of the Atmosphere at an Enormous Scale”