Earth’s Oxygen Could be Making the Moon Rust

Enhanced map of hematite (red) on Moon using a spheric projection (nearside only). Credit: Shuai Li

It takes oxygen to make iron rust. So when scientists discovered hematite spread widely through lunar high latitudes, they were surprised. How did that happen?

A new study suggests that oxygen from Earth could be playing a role in rusting the Moon.

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Did Snowball Earth Happen Because of a Sudden Drop in Sunlight?

This artist's illustration shows what an icy exo-Earth might look like. A new study says liquid water could persist under ice sheets on planets outside of their habitable zones. Image Credit: NASA

Hundreds of millions of years ago, Earth went through two episodes of severe glaciation. These two episodes—the Sturtian and the Marinoan glaciations—occured during the Earth’s Cryogenian Period. The Cryogenian lasted from about 720 million to 635 million years ago.

The phenomenon is called “Snowball Earth” and both instances of it happened in pretty quick succession. And while a planet encased in ice and snow sounds devastating, these episodes may have paved the way for the development of complex life.

The question is, what caused the Earth to freeze over like that?

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Lava Tubes on the Moon and Mars are Really, Really Big. Big Enough to Fit an Entire Planetary Base

The first lava tube skylight discovered on the moon. Image credit: JAXA/SELENE

Could lava tubes on the Moon and Mars play a role in establishing a human presence on those worlds? Possibly, according to a team of researchers. Their new study shows that lunar and Martian lava tubes might be enormous, and easily large enough to accommodate a base.

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What Cracked the Earth’s Outer Shell and Started its Plate Tectonics?

A snapshot of a model from the new work, showing the late stages of growth and coalescence of a new global fracture network. Fractures are in black / shadow, and colors show stresses (pink color denotes tensile stress, blue color denotes compressive stress). Image Credit: Tang et al, 2020.

Earth’s lithosphere is made up of seven large tectonic plates and a number of smaller ones. The theory of plate tectonics that describes how these plates move is about 50 years old. But there’s never really been an understanding of how this system developed, and how the Earth’s shell split into separate plates and started moving.

Now a group of researchers have a possible explanation.

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It Looks Like There are Still Active Volcanoes on Venus

A radar image of Maat Mons on Venus, from the Magellan spacecraft. Image Credit: NASA/JPL

Venus’ surface is no stranger to volcanoes. Radar images show more than 1,000 volcanic structures on the planet. But for the most part, they appear to be ancient and inactive.

Now a new study says that Venus is still volcanically active, and has identified 37 volcanic structures that were recently active. If true, there’s more going on inside Venus than thought.

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Earth’s Magnetic Field is Changing Surprisingly Quickly

Visual simulation of the Earth's magnetic field. Credit: NASA Goddard Space Flight Center

If you’ve ever used a compass, you know that the magnetic needle always points North. Well, almost North. If you just happen to be out camping for the weekend, the difference doesn’t matter. For scientists studying the Earth’s interior, the difference is important. How Earth’s magnetic field changes over time give us clues about how our planet generates a magnetic field in the first place.

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Why Lava Tubes Should be Our Top Exploration Priority on Other Worlds

Spectacular high Sun view of the Mare Tranquillitatis pit crater revealing boulders on an otherwise smooth floor. The 100 meter pit may provide access to a lunar lava tube. Image Credit: By NASA/GSFC/Arizona State University - http://photojournal.jpl.nasa.gov/catalog/PIA13518, Public Domain, https://commons.wikimedia.org/w/index.php?curid=54853313

When magma comes out of the Earth onto the surface, it flows as lava. Those lava flows are fascinating to watch, and they leave behind some unique landforms and rocks. But a lot of what’s fascinating about these flows can be hidden underground, as lava tubes.

These lava tubes are turning out to be a very desirable target for exploration on other worlds, just as they are here on Earth.

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It Was Almost Certainly an Asteroid Impact that Wiped Out the Dinosaurs. In Fact, Volcanoes Might Have Helped Life Recover

An ankylosaurus enjoying a drink of water while the asteroid strikes in the distance. Image Credit: Fabio Manucci

It seems almost certain that an asteroid impact wiped out the dinosaurs. But only almost. Another competing theory won’t completely go away: the extinction-by-volcano theory.

A new study from the UK piles more evidence on the asteroid side of the debate, while adding a new volcanic twist. These researchers say that volcanic activity actually helped life recover from the asteroid strike.

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Deep Down in Ocean Worlds, it’s Difficult to Tell Where the Oceans End and the Rock Begins

This artist’s concept shows a hypothetical planet covered in water around the binary star system of Kepler-35A and B. The composition of such water worlds has fascinated astronomers and astrophysicists for years. (Image by NASA/JPL-Caltech.)

We all know what water is. And what rock is. The difference is crystal clear. Well, here on Earth it is.

But on other worlds? The difference might not be so clear.

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