Chemistry Archives

February 9, 2023February 9, 2023 by Evan Gough

The Raw Materials for Life Form Early on in Stellar Nurseries

This is a two-panel mosaic of part of the Taurus Giant Molecular Cloud, the nearest active star-forming region to Earth. The darkest regions are where stars are being born. Inside these vast clouds, complex chemicals are also forming. Image Credit: Adam Block /Steward Observatory/University of Arizona

Life doesn’t appear from nothing. Its origins are wrapped up in the same long, arduous process that creates the elements, then stars, then planets. Then, if everything lines up just right, after billions of years, a simple, single-celled organism can appear, maybe in a puddle of water on a hospitable planet somewhere.

It takes time for the building blocks of stars and planets to assemble in space, and the building blocks of life are along for the ride. But there are significant gaps in our understanding of how all that works. A new study is filling in one of those gaps.

January 3, 2023January 3, 2023 by Evan Gough

Minerals Could Form on Mars Without an Oxygen-Rich Atmosphere

This scene shows NASA's Curiosity Mars rover at a location called "Windjana," where the rover found rocks containing manganese-oxide minerals, which require abundant water and strongly oxidizing conditions to form. Credits: NASA/JPL-Caltech/MSSS

Earth’s oxygen-rich atmosphere does more than provide the foundation for complex life. The oxygen in the atmosphere is so reactive that it readily combines with other chemical elements. Together, they form important ores like iron oxides and manganese oxides found in the Earth’s crust. So, when rovers spotted manganese oxides on Mars, scientists interpreted them as clues to Mars’ earlier atmosphere: it must have contained oxygen.

But a new study puts the brakes on that idea.

December 21, 2022December 21, 2022 by Evan Gough

Comet Impacts Could Have Brought the Raw Ingredients for Life to Europa’s Ocean

An artist's concept of a comet or asteroid impact on Jupiter's moon Europa. Credit: NASA/JPL-Caltech

Jupiter is the most-visited planet in the Solar System, thanks largely to NASA. It all started with Pioneer 10 and 11, followed by Voyager 1 and 2. Those were all flyby missions, and it wasn’t until 1996 that the Galileo spacecraft became the first to orbit the gas giant and even send a probe into its atmosphere. Then in 2016, the Juno spacecraft entered orbit around Jupiter and is still there today.

All of these missions were focused on Jupiter, but along the way, they gave us tantalizing hints of the icy moon Europa. The most impactful thing we’ve learned is that Europa, though frozen on the surface, holds an ocean under all that ice. And that warm, salty ocean might contain more water than all of Earth’s oceans combined.

Might it hold life?

December 8, 2022December 8, 2022 by Evan Gough

Meteorites Bathed in Gamma Rays Produce More Amino Acids and Could Have Helped Life get Going on Earth

Carbonaceous chondrites like the Allende meteorite contain significant amounts of water and amino acids. Could they have delivered amino acids to early Earth and spurred on the development of life? Image Credit: By Shiny Things - originally posted to Flickr as AMNH - Meteorite, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=4196153

Our modern telescopes are more powerful than their predecessors, and our research is more focused than ever. We keep discovering new things about the Solar System and finding answers to long-standing questions. But one of the big questions we still don’t have an answer for is: ‘How did life on Earth begin?’

October 28, 2022October 28, 2022 by Evan Gough

The Most Devastating Solar Storms in History are Scoured Into Tree Rings

Scientists study tree rings because they retain a record of climatic events and changes. They also record the Sun's activity. Image Credit: Rbreidbrown/Wikimedia Commons, CC BY-SA

Trees are like sentinels that preserve a record of shifting climates. Their growth rings hold that history and dendrochronology studies those rings. Scientists can determine the exact ages of trees and correlate their growth with climatic and environmental changes.

But they also record the effects of more distant changes, including the Sun’s activity.

October 21, 2022October 21, 2022 by Evan Gough

Early Life on Mars Might Have Wiped Out Life on Mars

Even though Mars and Earth had similar early histories, including water, Mars still ended up with fewer minerals than Earth. Why? Image Credit: ESO/M. Kornmesser

Life might have wiped itself out on early Mars. That’s not as absurd as it sounds; that’s sort of what happened on Earth.

But life on Earth evolved and persisted, while on Mars, it didn’t.

October 19, 2022October 19, 2022 by Evan Gough

The Heaviest Element Ever Seen in an Exoplanet’s Atmosphere: Barium

exoplanet hot jupiter transiting its star — This artist’s impression shows an ultra-hot exoplanet as it is about to transit in front of its host star. Credit: ESO

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.

October 18, 2022October 18, 2022 by Evan Gough

Scientists Discover a New Way Exoplanets Could Make Oxygen; Unfortunately, it Doesn’t Require Life

Oxygen is a valuable biosignature because Earth is oxygen-rich, and because life made all that oxygen. But if we find oxygen in an exoplanet atmosphere does that mean life made it? Or is there an abiotic source of oxygen? Image Credit: NASA

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.

June 28, 2022June 28, 2022 by Evan Gough

Water Worlds Could Have Plumes of Nutrients Carried up From Down Below

This reprocessed colour view of Jupiter’s moon Europa was made from images taken by NASA's Galileo spacecraft in the late 1990s. Credit: NASA/JPL-Caltech

Earth’s oceans are one huge, uniform electrolyte solution. They contain salt (sodium chloride) and other nutrients like magnesium, sulphate, and calcium. We can’t survive without electrolytes, and life on Earth might look very different without the oceans’ electrolyte content. It might even be non-existent.

On Earth, electrolytes are released into the oceans from rock by different processes like volcanism and hydrothermal activity.

Are these life-enabling nutrients available on water worlds?

May 17, 2022May 18, 2022 by Carolyn Collins Petersen

Carbon-12 is an Essential Building Block for Life and Scientists Have Finally Figured Out How it Forms in Stars

Artist's impression of a red giant star. Their cores are cauldrons where carbon-12 is produced. — Artist’s impression of a red giant star. Their cores are cauldrons where carbon-12 is produced. Credit:NASA/ Walt Feimer

Each of us is, as it says in Max Ehrmann’s famous poem “Desiderata”, a child of the universe. It speaks metaphorically about our place in the cosmos, but it turns out to be a very literal truth. Our bodies contain the stuff of stars and galaxies, and that makes us children of the cosmos. To be more precise, we are carbon-based life forms. All life on Earth is based on the element carbon-12. It turns out this stuff is a critical gateway to life. So, how did the universe come up with enough of it to make you and me and all the life on our planet? Astrophysicists and nuclear physicists think they have an answer by using a supercomputer simulation of what happens to create carbon. As it turns out, it’s not very easy.