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.

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Should Planetary Defence Take Center Stage?

This illustration shows NASA's NEO Surveyor against an infrared observation of a starfield made by the agency's WISE mission. NEO Surveyor is the first purpose-built space telescope that will advance NASA’s planetary defense efforts by finding and tracking hazardous near-Earth objects. Credit: NASA/JPL-Caltech/University of Arizona

Throughout the Solar System, planets and moons bear the scars of a past fraught with collisions. The Moon, Mercury, and Mars are so scarred from these impacts that craters overlap one another on their surfaces. Earth was subject to the same bombardment, though most of its impact scars disappeared over time due to active geology.

But some are still visible, and we know how catastrophic some of these impacts were for life.

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Webb’s New Image Reveals a Galaxy Awash in Star Formation

This JWST image shows NGC 7469, a luminous, face-on spiral galaxy approximately 90 000 light-years in diameter that lies roughly 220 million light-years from Earth in the constellation Pegasus. Image Credit: ESA/Webb, NASA & CSA, L. Armus, A. S. Evans

When a spiral galaxy presents itself just right, observations reveal more detail. That’s the case with NGC 7469, a spiral galaxy about 220 million light-years away. It’s face-on towards us, and the James Webb Space Telescope captured its revealing scientific portrait.

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A Star Came too Close to a Black Hole. It Didn’t End Well

A disk of hot gas swirls around a black hole in this illustration. The stream of gas stretching to the right is what remains of a star that was pulled apart by the black hole. A cloud of hot plasma (gas atoms with their electrons stripped away) above the black hole is known as a corona. Credits: NASA/JPL-Caltech

Black holes are confounding objects that stretch physics to its limits. The most massive ones lurk in the centers of large galaxies like ours. They dominate the galactic center, and when a star gets too close, the black hole’s powerful gravitational force tears the star apart as they feed on it. Not even the most massive stars can resist.

But supermassive black holes (SMBHs) didn’t start out that massive. They attained their gargantuan mass by accreting material over vast spans of time and by merging with other black holes.

There are large voids in our understanding of how SMBHs grow and evolve, and one way astrophysicists fill those voids is by watching black holes as they consume stars.

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This Will Probably Be InSight’s Last Picture Before it Runs Out of Power Forever

This image shows InSight's landing spot and its SEIS instrument, covered with its protective wind shield. The lander's been having trouble generating electricity and this could be its final image. Image Credit: NASA/JPL

The InSight lander might have transmitted its last picture from the surface of Mars. It looks like the lander is succumbing to Mars’ dusty conditions, as its ability to generate energy from its solar panels has been declining in recent weeks.

It’s always sad and somehow poignant when a lander or a rover falls silent. Each of them has a personality that goes along with their mission. But we’ve known for months this day was coming.

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Webb Stares Deeply Into the Universe, Showing How Galaxies Assemble

This image represents a portion of the full PEARLS field, which will be about four times larger. Thousands of galaxies over an enormous range in distance and time are seen in exquisite detail, many for the first time. Image Credit: SCIENCE: NASA, ESA, CSA, Rolf A. Jansen (ASU), Jake Summers (ASU), Rosalia O'Brien (ASU), Rogier Windhorst (ASU), Aaron Robotham (UWA), Anton M. Koekemoer (STScI), Christopher Willmer (University of Arizona), JWST PEARLS Team IMAGE PROCESSING: Rolf A. Jansen (ASU), Alyssa Pagan (STScI)

The James Webb Space Telescope is delivering a deluge of images and data to eager scientists and other hungry-minded people. So far, the telescope has shown us the iconic Pillars of Creation like we’ve never seen them before, the details of very young stars as they grow inside their dense cloaks of gas, and a Deep Field that’s taken over from the Hubble’s ground-breaking Deep Field and Ultra Deep Field images. And it’s only getting started.

True to its main science objectives, the JWST has peered back in time to the Universe’s earliest galaxies looking for clues to how they assemble and evolve.

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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?

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We Could Spread Life to the Milky Way With Comets. But Should We?

Gerald Rhemann captured this incredible image of Comet Leonard when a piece of the comet's tail was disconnected and carried away. Rhemann won Astronomy Photographer of the Year 2022 for the image. Image Credit: Gerald Rhemann

Here’s a thorny problem: What if life doesn’t always appear on planets that can support it? What if we find more and more exoplanets and determine that some of them are habitable? What if we also determine that life hasn’t appeared on them yet?

Could we send life-bringing comets to those planets and seed them with terrestrial life? And if we could do that, should we?

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JWST Sees Furious Star Formation in a Stellar Nursery

Image of the Carina Nebula (NGC 3324) captured by Webb’s Near-Infrared Camera (NIRCam), Credit: NASA/ESA/CSA/STScI

The powerful James Webb Space Telescope is a mighty technological tool. Astrophysicists first conceived it over 20 years ago, and after many twists and turns, it was launched on December 2st, 2021. Now it’s in a halo orbit at the Sun-Earth L2 point, where it will hopefully continue operating for 20 years.

It’s only been a few months since its first images were released, and it’s already making progress in answering some of the Universe’s most compelling questions. In a newly-released image, the JWST peered deep inside massive clouds of gas and dust to watch young stars come to life in their stellar cocoons.

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Are Planets Tidally Locked to Red Dwarfs Habitable? It’s Complicated

habitable exoplanet interstellar message
Artist's impression of the exoplanet Ross 128 b orbiting its red dwarf star. Potetentially habitable rocky worlds like this one are beyond our physical reach. Image Credit: ESO/M. Kornmesser. Public Domain

Astronomers are keenly interested in red dwarfs and the planets that orbit them. Up to 85% of the stars in the Milky Way could be red dwarfs, and 40% of them might host Earth-like exoplanets in their habitable zones, according to some research.

But there are some problems with their potential habitability. One of those problems is tidal locking.

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