Category Astronomy/Space

Hidden magma oceans could shield rocky exoplanets from harmful radiation

Illustration of a super-earth shown with cross-sections revealing the deep layer of molten rock known as the basal magma ocean that could produce magnetic fields for super-earths.
UNDER ARMOR? Deep layers of molten rock inside some super-earths could generate powerful magnetic fields—potentially stronger than Earth’s—and help shield these exoplanets from harmful radiation. (University of Rochester Laboratory for Laser Energetics illustration / Michael Franchot)

Deep beneath the surface of distant exoplanets known as super-Earths, oceans of molten rock may be doing something extraordinary: powering magnetic fields strong enough to shield entire planets from dangerous cosmic radiation and other harmful high-energy particles.

Earth’s magnetic field is generated by movement in its liquid iron outer core—a process known as a dynamo—but larger rocky worlds like super-Earths might have solid or fully liquid cores that cannot produce magnetic fields in the sam...

Read More

Researchers solve mystery of universe’s ‘little red dots’

Red dots
The little red dots are young black holes, enshrouded in a cocoon of gas, which they are consuming in order to grow larger. This process generates enormous heat which gives little red dots their unique red colour. Photo: JWST/Darach Watson

Since the James Webb Space Telescope (JWST) went into operation, red dots in its images have puzzled researchers around the world. Now, researchers from the University of Copenhagen have explained these enigmatic findings, revealing the most violent forces in the universe concealed in a cocoon of ionized gas. The discovery is published in Nature.

Since December 2021, when the James Webb super telescope saw first light, some 1...

Read More

Spaceflight causes astronauts’ brains to shift, stretch and compress in microgravity

iss
Credit: CC0 Public Domain

Spaceflight takes a physical toll on astronauts, causing muscles to atrophy, bones to thin and bodily fluids to shift. According to a new study published in the journal PNAS, we can now add another major change to that list. Being in microgravity causes the brain to change shape.

Here on Earth, gravity helps to keep the brain anchored in place while the cerebrospinal fluid that surrounds it acts as a cushion. Scientists already knew that, without gravity’s steady pull, the brain moves upward, but this new research showed that it is also stretched and compressed in several areas.

Brains on the move
Researchers led by Rachel Seidler at the University of Florida reached this conclusion after studying MRI scans of 26 astronauts taken before and after their mi...

Read More

Tiny Mars’s big impact on Earth’s climate: How the red planet’s pull shapes ice ages

At half the size of Earth and one-tenth its mass, Mars is a featherweight as far as planets go. Yet new research reveals the extent to which Mars is quietly tugging on Earth’s orbit and shaping the cycles that drive long-term climate patterns here, including ice ages.

The study is published in the journal Publications of the Astronomical Society of the Pacific.

Stephen Kane, a professor of planetary astrophysics at UC Riverside, began this project with doubts about recent studies tying Earth’s ancient climate patterns to gravitational nudges from Mars. These studies suggest that sediment layers on the ocean floor reflect climate cycles influenced by the red planet despite its distance from Earth and small size.

“I knew Mars had some effect on Earth, but I assumed it was tiny,...

Read More