Cosmic Dust Could Have Helped Get Life Going on Earth

By Brian Koberlein - February 24, 2024 01:38 PM UTC | Astrobiology
The early Earth didn't have many chemicals needed for life on its surface, but they were present in asteroids and comets. Astronomers think they were delivered by countless objects crashing into the planet early in its history. But there's also a constant rain of organic-rich cosmic dust entering the Earth's atmosphere, and some can even pile up into sedimentary deposits left behind by glaciers. Did cosmic dust help fertilize prebiotic chemistry?
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We Could Snoop on Extraterrestrial Communications Networks

By Brian Koberlein - February 22, 2024 02:07 PM UTC | Astrobiology
SETI researchers have directed their search toward interesting star systems where extraterrestrial civilizations could send signals toward Earth. According to a new paper, sufficiently advanced civilizations will communicate across the galaxy, sending signals between stars, rogue planets, and interstellar objects. They'll probably be using pulsars as a navigation system to coordinate their activities at a vast scale. To confirm their existence, we just have to listen in.
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Gravastars are an Alternative Theory to Black Holes. Here's What They'd Look Like

By Brian Koberlein - February 19, 2024 12:17 PM UTC | Black Holes
Astronomers continue to find more and more evidence of black holes, but there's an alternative theory that could explain the observations: gravastars. First proposed in 2001, these objects are one possible solution to Einstein's field equations, having the same impact on the Universe. But they won't have an event horizon or singularity. Instead, they'd contain thin shells of matter surrounding an exotic dark energy that pushes back against the star's gravitational force.
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