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.

Continue reading “Minerals Could Form on Mars Without an Oxygen-Rich Atmosphere”

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?

Continue reading “Comet Impacts Could Have Brought the Raw Ingredients for Life to Europa’s Ocean”

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?’

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

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.

Continue reading “The Most Devastating Solar Storms in History are Scoured Into Tree Rings”

Early Life on Mars Might Have Wiped Out Life on Mars

Primitive simple life may have thrived on early Mars. Then it may have wiped itself out. Is it too late for a memorial? 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.

Continue reading “Early Life on Mars Might Have Wiped Out Life on Mars”

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.

Continue reading “The Heaviest Element Ever Seen in an Exoplanet’s Atmosphere: Barium”

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.

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

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?

Continue reading “Water Worlds Could Have Plumes of Nutrients Carried up From Down Below”

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.

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

Astronomers Find a Star That Contains 65 Different Elements

This is an image of M80, an ancient globular cluster of stars. Since these stars formed in the early universe, their metallicity content is very low. This means that gas giants like Jupiter would be rare or non-existent here, while brown dwarfs are likely plentiful. Image: By NASA, The Hubble Heritage Team, STScI, AURA - Great Images in NASA Description, Public Domain, https://commons.wikimedia.org/w/index.php?curid=6449278
This is an image of M80, an ancient globular cluster of stars. Since these stars formed in the early universe, their metallicity content is very low. This means that gas giants like Jupiter would be rare or non-existent here, while brown dwarfs are likely plentiful. Image: By NASA, The Hubble Heritage Team, STScI, AURA - Great Images in NASA Description, Public Domain, https://commons.wikimedia.org/w/index.php?curid=6449278

Have you ever held a chunk of gold in your hand? Not a little piece of jewelry, but an ounce or more? If you have, you can almost immediately understand what drives humans to want to possess it and know where it comes from.

We know that gold comes from stars. All stars are comprised primarily of hydrogen and helium. But they contain other elements, which astrophysicists refer to as a star’s metallicity. Our Sun has a high metallicity and contains 67 different elements, including about 2.5 trillion tons of gold.

Now astronomers have found a distant star that contains 65 elements, the most ever detected in another star. Gold is among them.

Continue reading “Astronomers Find a Star That Contains 65 Different Elements”