Category Astronomy/Space

Water is essential for life on Earth and other planets, and scientists have found ample evidence of water in Mars’ early history. But Mars has no liquid water on its surface today. New research from Washington University in St. Louis suggests a fundamental reason: Mars may be just too small to hold onto large amounts of water.

Remote sensing studies and analyses of Martian meteorites dating back to the 1980s posit that Mars was once water-rich, compared with Earth. NASA’s Viking orbiter s1pacecraft—and, more recently, the Curiosity and Perseverance rovers on the ground—returned dramatic images of Martian landscapes marked by river valleys and flood channels.

Despite this evidence, no liquid water remains on the surface...

Researchers at the University of Illinois Urbana-Champaign watched fragments of two meteors as they ramped up the heat from room temperature to the temperature it reaches as it enters Earth’s atmosphere and made a significant discovery. The vaporized iron sulfide leaves behind voids, making the material more porous. This information will help when predicting the weight of a meteor, its likelihood to break apart, and the subsequent damage assessment if it should land.

“We extracted samples from the interiors that had not already been exposed to the high heat of the entry environment,” said Francesco Panerai, professor in the Department of Aerospace Engineering at UIUC. “We wanted to understand how the microstructure of a meteorite changes as it travels through the atmosphere.”

Pa...

While black holes and toddlers don’t seem to have much in common, they are remarkably similar in one aspect: Both are messy eaters, generating ample evidence that a meal has taken place.

But whereas one might leave behind droppings of pasta or splatters of yogurt, the other creates an aftermath of mind-boggling proportions. When a black hole gobbles up a star, it produces what astronomers call a “tidal disruption event...

Star-forming galaxies are responsible for creating gamma-rays that until now had not been associated with a known origin, researchers from The Australian National University (ANU) have confirmed.

Lead author Dr. Matt Roth, from the ANU Research School of Astronomy and Astrophysics, said until now it has been unclear what created gamma-rays—one of the most energetic forms of light in the Universe—that appear in patches of seemingly “empty sky.”

The discovery could offer clues to help astronomers solve other mysteries of the Universe, such as what kind of particles make up Dark Matter—one of the holy grails of astrophysics.

“It’s a significant milestone to finally discover the origins of this ga...