Mars did Have Moving Glaciers, but They Behaved Differently in the Planet's Lower Gravity

Glacial landscapes on Axel Heiberg Island (Canadian Arctic Archipelago) showing typical (glaciers) and atypical (subglacial channels, bottom right) glacial landscapes. Credit: A. Grau Galofre

On Earth, shifts in our climate have caused glaciers to advance and recede throughout our geological history (known as glacial and inter-glacial periods). The movement of these glaciers has carved features on the surface, including U-shaped valleys, hanging valleys, and fjords. These features are missing on Mars, leading scientists to conclude that any glaciers on its surface in the distant past were stationary. However, new research by a team of U.S. and French planetary scientists suggests that Martian glaciers did move more slowly than those on Earth.

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More Rocket Launches Could Damage the Ozone Layer

There are few things in this world that brings feelings of awe and wonder more than a rocket launch. Watching a literal tower of steel slowly lift off from the ground with unspeakable power reminds us of what humanity can achieve despite our flaws, disagreements, and differences, and for the briefest of moments these magnificent spectacles are capable of bringing us all together regardless of race, creed, and religion.

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The Rapid Changes We’re Seeing With the Earth’s Magnetic Field Don’t Mean the Poles are About to Flip. This is Normal

An illustration of Earth's magnetic field. Image Credit: ESA/ATG medialab

One of the most interesting discoveries about Earth in the past few decades concerns the Earth’s magnetic poles. Paleomagnetic records show that the poles have flipped places 183 times in the last 83 million years. That’s about every 450,000 years on average, though there were ten million years between flips in at least two cases.

The Earth’s magnetic field is experiencing some rapid changes right now, but scientists say that has no relation to pole flipping.

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Antarctica Lost an Ice Shelf, but Gained an Island

The eastern coast of Antarctica has lost most of the Glenzer and Conger ice shelves, as seen in these satellite images taken between November 15, 1989 - January 9, 2022. Credit: NASA GSFC/UMBC JCET.

Collapsing ice shelves on the eastern coast of Antarctica has revealed something never seen before: a landform that might be an island. But this is not the first newly revealed island off the Antarctic coast. A series of islands have appeared as the ice shelves along the continent’s coastline has disintegrated over the past few years.

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Just a Few Pixels Would let Astronomers Map Surface Features on an Exoplanet Like Oceans and Deserts

Direct images of exoplanets are rare and lack detail. Future observatories might change that, but for now, exoplanet images don’t tell researchers very much. They merely show the presence of the planets as blobs of light.

But a new study shows that only a few pixels can help us understand an exoplanet’s surface features.

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Marsquakes are Caused by Shifting Magma

Mars' interior as revealed by the NASA/DLR InSight lander. Image Credit: Cottar, Koelemeijer, Winterbourne, NASA

Before the InSight Lander arrived on Mars, scientists could only estimate what the planet’s internal structure might be. Its size, mass, and moment of inertia were their main clues. Meteorites, orbiters, and in-situ sampling by rovers provided other clues.

But when InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) arrived on Mars in November 2018 and deployed its seismometer, better data started streaming in.

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Primordial Helium, Left Over From the Big Bang, is Leaking Out of the Earth

The center of Lagoon Nebula, captured by the Hubble Telescope. Nebulae are the primary sources of helium-3, and the amount of He-3 leaking from the Earth’s core suggests the planet formed inside the solar nebula, according to a new study in the AGU journal Geochemistry, Geophysics, Geosystems. Credit: NASA, ESA

Something ancient and primordial lurks in Earth’s core. Helium 3 (3He) was created in the first minutes after the Big Bang, and some of it found its way through time and space to take up residence in Earth’s deepest regions. How do we know this?

Scientists can measure it as it slowly escapes.

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The Building Blocks of Earth Could Have Come From Farther out in the Solar System

Artist's impression of the asteroid belt. Image credit: NASA/JPL-Caltech

Earth formed over 4.5 billion years ago via accretion. Earth’s building blocks were chunks of rock of varying sizes. From dust to planetesimals and everything in between. Many of those chunks of rock were carbonaceous meteorites, which scientists think came from asteroids in the outer reaches of the main asteroid belt.

But some evidence doesn’t line up well behind that conclusion. A new study says that some of the Earth-forming meteorites came from much further out in the Solar System.

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How did Earth go From Molten Hellscape to Habitable Planet?

An artist's impression of the Hadean eon. Image Credit: By Tim Bertelink - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=48916334

Earth formed from the Sun’s protoplanetary disk about 4.6 billion years ago. In the beginning, it was a molten spheroid with scorching temperatures. Over time, it cooled, and a solid crust formed. Eventually, the atmosphere cooled, and life became a possibility.

But how did all of that happen? The atmosphere was rich in carbon, and that carbon had to be removed before the temperature could drop and Earth could become habitable.

Where did all the carbon go?

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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.

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