A Monster Solar Storm Struck Earth 14,300 Years Ago

By Brian Koberlein - October 16, 2023 02:51 PM UTC | Solar Astronomy
Because of our dependence on technology, a powerful solar storm would be a catastrophe, shutting down the electrical grid and deactivating satellites. Researchers studying tree rings have found what they think is the most powerful solar storm ever to hit our planet - 14,300 years ago. So far, scientists have found nine extreme solar storms, called Miyake Events, in the last 15,000 years, but this newly identified one is twice as powerful as anything found.
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Are Pulsars the Key to Finding Dark Matter?

By Brian Koberlein - October 13, 2023 01:00 PM UTC | Physics
The search for dark matter continues, with astronomers developing new hypotheses to search for this invisible gravitational influence on the Universe. One proposed dark matter particle candidate is the axion, which physicists have searched for since the 1970s. One characteristic of axions is that they should convert into light in a strong electromagnetic field. According to a new paper, they should create a faint glow around pulsars, generating intense magnetic fields.
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More JWST Observations are Finding Fewer Early Massive Galaxies

By Brian Koberlein - October 12, 2023 01:31 PM UTC | Extragalactic
Astronomers using JWST were surprised to find mature-looking galaxies in the early Universe; they challenged existing models of cosmology. Astronomers wanted to see if these were ubiquitous, so they examined 19 galaxies in a different part of the sky. They measured high-redshift galaxies but did not find the same unusual mass distribution. This led them to suggest that those initial discoveries were outliers and not indicative of the early Universe.
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A Pulsar Suddenly Threw Out Radiation 200 Times More Energetic

By Brian Koberlein - October 09, 2023 10:16 AM UTC | Physics
Pulsars are so dependable you could set your watch to them, sometimes turning hundreds of times a second with incredible accuracy. One well-studied pulsar suddenly unleashed a torrent of radiation 200 times more energetic than anything astronomers had seen from this object before. The radiation levels were so high that it challenged established theories about how particles are accelerated by the powerful magnetic fields surrounding the pulsar. What's going on?
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Here's What it Would Take to See a Black Hole's Photon Ring

By Brian Koberlein - October 08, 2023 11:34 AM UTC | Black Holes
In 2019, the Event Horizon Telescope gave us the first-ever image of a black hole's event horizon, revealing the area around the heart of M87. The event horizon is the closest we've seen to a black hole, but not the closest we can see. That would be the photon ring, where light itself is pulled into orbit around the black hole. To build an observatory that can see the photon ring, we'll have to extend the Event Horizon Telescope to space, creating an even larger virtual telescope that might include the Earth and various Lagrange points.
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Starlinks are Easily Detected by Radio Telescopes

By Brian Koberlein - October 07, 2023 12:31 PM UTC | Observing
Visible and infrared astronomers are concerned about light pollution from satellite megaconstellations, and radio astronomers should be concerned too. A team of astronomers used radio telescopes in Australia to image the sky as Starlink satellites overhead. The tests were done at the future Square Kilometer Array facility in Western Australia, using prototype stations that will become part of the array. According to the team, the satellites were easily detectable, and they could see them performing periodic bursts and steady transmissions. When the full SKA comes online, satellites will be another source of radio interference to contend with.
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What Caused Eta Carinae's 1840 "Great Eruption?"

By Brian Koberlein - October 06, 2023 12:07 PM UTC | Stars
n 1840, a seemingly innocuous star, Eta Carinae, suddenly brightened to become one of the brightest stars in the sky before slowly fading again. We now know that Eta Carinae is one of the most massive stars in the Milky Way, and this event - dubbed "the Great Eruption" - released 10 to 45 times the mass of the Sun into space. And yet, the star survived. What happened? The Chandra X-Ray Observatory has peered at the star and helped astronomers discover new details about the explosion and what might have led to this event.
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