We already know that Gale Crater on Mars used to hold a lake or series of lakes a few billion years ago. Now, NASA’s Curiosity rover has found evidence for ancient giant floods that washed through the region as well. Source: https://earthsky.org/space/megafloods-gale-crater-mars-life-curiosity-rover…
Tag: measurements
The universe is expanding too fast, and that could rewrite cosmology
Different measurements of the Hubble constant, the rate of space-time expansion, refuse to agree – meaning we may have to look beyond Einstein’s theories to explain the universe Source: https://www.newscientist.com/article/mg24833100-800-the-universe-is-expanding-too-fast-and-that-could-rewrite-cosmology/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home…
To Explain Away Dark Matter, Gravity Would Have To Be Really Weird
To discard the theory of dark matter, “you’ll need to replace it with something even more bizarre: a force of gravity that, at some distances, pulls massive objects together and, at other distances, pushes them apart.” That’s how Science magazine describes a new study, adding that “The analysis underscores how hard it is to explain away dark matter” — even though…
Will SpaceX’s Starlink satellites ruin stargazing?
SpaceX’s satellites will populate the night sky, affecting how we observe the stars. And this is just the beginning of private satellite mega-constellations. Source: https://earthsky.org/human-world/will-spacex-starlink-satellites-ruin-stargazing…
‘Extremely Aggressive’ Internet Censorship Spreads In the World’s Democracies
Researchers from the University of Michigan used their own automated censorship tracking system to collect more than 21 billion measurements over 20 months in 221 countries. They discovered that citizens in what are considered the world’s freest countries aren’t safe from internet censorship. From a press release: [Roya Ensafi, U-M assistant professor of electrical engineering and computer science who led the…
Bellatrix is Orion’s 3rd-brightest star
The bluish-white shoulder star, Bellatrix, aka Gamma Orionis, has a name that means “female warrior.” Bellatrix is one of the hottest stars you can see without optical aid. Source: https://earthsky.org/brightest-stars/bellatrix-3rd-brightest-star-in-orion…
Scientists discover ancient lake bed deep beneath Greenland ice
The ancient lake bed, sealed more than a mile under Greenland ice, may be hundreds of thousands or millions of years old, and contain unique fossil and chemical traces of past climates and life. Source: https://earthsky.org/earth/ancient-lake-bed-deep-beneath-greenland-ice…
What is a supernova?
A supernova is a star’s colossal explosion at the end of its life, potentially outshining its entire galaxy. Read about the causes and types of supernovae here. Source: https://earthsky.org/astronomy-essentials/definition-what-is-a-supernova…
Chinese Glaciers Melting At ‘Shocking’ Pace, Scientists Say
An anonymous reader writes: Glaciers in China’s bleak Qilian mountains are disappearing at a shocking rate as global warming brings unpredictable change and raises the prospect of crippling, long-term water shortages, scientists say. The largest glacier in the 800-kilometer (500-mile) mountain chain on the arid northeastern edge of the Tibetan plateau has retreated about 450 meters since the 1950s, when researchers…
Feeding a galaxy’s nuclear black hole
A galactic bar is the approximately linear structure of stars and gas that stretches across the inner regions of some galaxies. The bar stretches from one inner spiral arm, across the nuclear region, to an arm on the other side. Found in about half of spiral galaxies, including the Milky Way, bars are thought to funnel large amounts of gas into…