Humanity Will Out-Communicate all Life on Earth Within 90 Years

By Brian Koberlein - September 06, 2023 10:36 AM UTC | Astrobiology
All organisms communicate information with their cells using signaling molecules. Add up all these communications, and it's the equivalent of 10^24 bits per second, which is an incomprehensibly large amount. Humanity's digital communication only amounts to 10^15 bits per second, nine orders of magnitude less. However, humanity's information transmission is growing exponentially, and according to a new study, it should catch up within 90 years. These estimates could help astronomers search for technological civilizations more advanced than us.
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A New Telescope Could Detect Decaying Dark Matter in the Early Universe

By Brian Koberlein - September 05, 2023 01:14 PM UTC | Cosmology
A gap in astronomical knowledge is Cosmic Dawn, a time when the first stars in the Universe formed, ending the cosmological dark ages. If there was dark matter at this early time, its decay might have heated up the intergalactic medium, sending out a signal that could be detectable today. A new paper suggests that the newly built Hydrogen Epoch of Reionization Array (HERA) telescope could measure this dark matter decay with 1,000 hours of observation or constrain its presence by three orders of magnitude.
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It's Going to Take More Than Early Dark Energy to Resolve the Hubble Tension

By Brian Koberlein - September 04, 2023 03:00 PM UTC | Cosmology
Astronomers have measured the Universe's expansion rate and found that various methods don't agree, and their error bars don't overlap. This is called the "Hubble Tension" or the "Crisis in Cosmology." Either the measurements are wrong, or new physics is waiting to be discovered. Cosmologists have proposed a period of rapid expansion early on in the Universe called "Early Dark Energy." Still, a recent paper suggests one rapid expansion event wouldn't explain other observations about the Universe. It's probably a combination of factors.
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The Closest Supernova Seen in the Modern Era, Examined by JWST

By Brian Koberlein - September 03, 2023 10:40 AM UTC | Extragalactic
In 1987, a supernova suddenly appeared in the Large Magellanic Cloud and was studied by astronomers worldwide. Although the detonating star was 165,000 light-years away, this was still the closest supernova seen in centuries. Astronomers have continued to study the expanding debris cloud over the decades, and now JWST has joined the effort, revealing new features never before seen with other observatories. The central core is so dense with gas and dust that its central neutron star remnant is still hidden, even to JWST.
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Astronomers are Hoping the Event Horizon Telescope saw Pulsars Near the Milky Way's Supermassive Black Hole

By Brian Koberlein - September 02, 2023 09:55 AM UTC | Black Holes
The Event Horizon Telescope is a collection of radio telescopes across the globe that simultaneously gathered data about the Milky Way's supermassive black hole, acting as a single telescope the size of planet Earth. This revealed the galaxy's heart in unprecedented detail, helping to confirm the black hole's event horizon and prove some of Einstein's predictions about General Relativity. But if those observations happened to contain any signals from pulsars in the area, it would allow for even more precise measurements, as if there were atomic clocks orbiting Sgr A*.
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If Earth Was an Exoplanet, JWST Would Know There's an Intelligent Civilization Here

By Brian Koberlein - September 01, 2023 11:51 AM UTC | Astrobiology
JWST is the most powerful instrument astronomers have to study the atmospheres of exoplanets, looking for trace gases that might indicate life on another world. What if Earth was an exoplanet orbiting a nearby star? What could JWST learn about our planet? In a new study, astronomers took observations of Earth from various spacecraft and then simulated what JWST would see if it got our home planet in the crosshairs. The telescope could detect various chemicals, from water vapor to methane, but it could also sense the presence of chlorofluorocarbons resulting from our industrial infrastructure.
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Do Advanced Civilizations Know We're Here?

By Brian Koberlein - August 31, 2023 10:41 AM UTC | Astrobiology
Although humans have only sent a couple of tentative signals into space, many are concerned about the risks. Should we let alien civilizations know we're here? According to a new paper, humanity has already been broadcasting its existence for thousands of years, and civilizations with advanced enough technology should be able to observe us. It's science fiction to us, but megastructure space telescopes could have baselines of millions of kilometers, powerful enough to detect structures on the surface of Earth from thousands of light-years away.
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It's Time for a Gravitational Wave Observatory in the Southern Hemisphere

By Brian Koberlein - August 30, 2023 10:48 AM UTC | Physics
All current and planned gravitational wave observatories are located in the northern hemisphere, in the US, India, Europe, and Japan. Even the next-generation observatories like Cosmic Explorer 40-km and the Einstein Telescope will be in the north. But a telescope in the southern hemisphere would provide a much larger baseline, allowing the detection of fainter gravitational waves. A new paper makes the case for building an observatory south of the equator.
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Astronomers Precisely Measure a Black Hole's Accretion Disk

By Brian Koberlein - August 29, 2023 12:56 PM UTC | Black Holes
Actively feeding supermassive black holes are known as quasars, and they can outshine all the stars of their host galaxy. Part of their brightness comes from the accretion disk surrounding the black hole, but they're hard to image directly because quasars are so far away. New data from one of the world's largest telescopes has managed this feat, detecting near-infrared emission lines that mark significant regions in the accretion disk in a quasar.
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The Early Universe Should Be Awash in Active Galaxies, but JWST Isn't Finding Them

By Brian Koberlein - August 27, 2023 12:47 PM UTC | Cosmology
Astronomers have found supermassive black holes in the centers of most galaxies. To get the black holes we see today, they must have been feeding in the past, packing on the mass to grow so big. But, a recent survey with JWST failed to turn up as many active galactic nuclei as astronomers expected. This just deepens the mystery. How did mature galaxies like the Milky Way get their black holes if they didn't go through this feeding period?
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Pulsars Detected the Background Gravitational Hum of the Universe. Now Can They Detect Single Mergers?

By Brian Koberlein - August 26, 2023 11:35 AM UTC | Physics
After over a decade of observations of pulsars, astronomers could finally tease out the gravitational wave background of the Universe, the combined signal from merging supermassive black holes. But it was just the general presence of mergers, not specific events. A new paper proposes that the same pulsars could next be used to detect the gravitational waves from individual merging supermassive black holes. The more nearby pulsars astronomers can find, the more accurate their measurements will become.
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A Giant Black Hole Destroyed a Star and Threw the Pieces Into Space

By Brian Koberlein - August 25, 2023 12:17 PM UTC | Black Holes
A pair of X-ray telescopes have observed the messy aftermath of a star that came too close to a supermassive black hole 290 million light-years away. It's believed that the star had three times the mass of the Sun, so this was one of the largest tidal disruption events ever seen. Although the black hole consumed some of the star, most of its guts were thrown into the surrounding space, polluting the region with the chemicals that allowed astronomers to estimate its stellar mass.
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TESS Has Found Thousands of Possible Exoplanets. Which Ones Should JWST Study?

By Brian Koberlein - August 24, 2023 01:43 PM UTC | Exoplanets
JWST has demonstrated how well it can analyze the atmosphere of exoplanets, revealing carbon dioxide, water vapor, and sulfur compounds. The hope, of course, is that it might be able to find evidence of biosignatures. Astronomers have found over 5,000 confirmed exoplanets, and TESS has turned up 4,000 candidate exoplanets. With this enormous catalog of confirmed and potential planets, which are high priorities that JWST should be pointed at?
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The Irony. ClearSpace-1 Couldn't Clean up Space Debris Because its Target Already Got hit by Space Debris, Creating Even More Space Debris.

By Brian Koberlein - August 23, 2023 09:49 AM UTC | Space Policy
The European Space Agency's ClearSpace-1 satellite was zeroing in on the spent payload adaptor from a 2013 rocket launch. Its task would be to extend arms, grab the chunk of debris, hug it tightly, and then pull it back into the Earth's atmosphere, de-orbiting and removing it from low-Earth orbit. On August 10th, mission controllers detected multiple pieces of space debris near its target - debris that was probably dislodged from it in the recent past. They're now scrutinizing the situation to plan their next step in the mission.
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