Gravitational Lens Confirms the Hubble Tension

By Brian Koberlein - October 03, 2024 01:00 PM UTC | Cosmology
Astronomers want new ways to measure distance in the Universe, working to calculate its rate of expansion. A new image from JWST contains a gravitational lens of a background galaxy. And in that galaxy are three versions of the same Type 1a supernova, one of the most distant ever seen. With this supernova, astronomers are able to extend their distance ladder out by billions of years, and yet, it doesn't resolve the famous Hubble Tension; it only confirms it.
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Bernard's Star Has a Planet (Again)!

By Brian Koberlein - October 02, 2024 10:49 AM UTC | Exoplanets
The red dwarf Barnard's Star is the closest single star to the Sun, only six light-years away. Astronomers have announced the discovery of a planet with half the mass of Venus, orbiting the star every three days. This puts it too close to be in the habitable zone, with a surface temperature of 125 °C. The team also found a hint of three additional planets in the system but will require further observations to pin down their sizes and orbits.
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How Does the Milky Way Compare to Other Galaxies?

By Brian Koberlein - September 28, 2024 12:10 PM UTC | Extragalactic
Looking out into the universe, astronomers have identified countless spiral galaxies similar to the Milky Way. But is our home galaxy normal? A 10+ year survey called Satellites Around Galactic Analogs (SAGA) has been measuring galaxy systems like the Milky Way, including the companion satellite galaxies that surround them. They found that the Milky Way has fewer satellite galaxies than others with roughly the same size and mass.
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Martian Clay Could Be Hiding the Planet's Atmosphere

By Brian Koberlein - September 27, 2024 03:05 PM UTC | Planetary Science
We know that Mars was once a warmer, wetter world with a thicker atmosphere, but now it has 1% of the atmospheric density of Earth. Where did it all go? One theory is that billions of years of interaction with the solar wind have buffeted it off into space. New research suggests that the atmosphere might still be there, just bound up in the clay-covered material that forms the crust of Mars. Trickling water could have drawn CO2 out of the atmosphere and locked it away.
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Dark Matter Could a Have Slight Interaction With Regular Matter

By Brian Koberlein - September 26, 2024 08:39 AM UTC | Physics
Dark matter seems to be an invisible particle that only interacts with regular matter (or itself) through gravity. But in a new study, based on data gathered by Hubble, researchers think they've found evidence of interactions with regular matter beyond just gravity. They recorded the structure of a low-mass galaxy, measured the concentrations of dark matter, and then compared that to simulations where dark matter only interacts through gravity and found a discrepancy.
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Biosignatures Can be Made in the Lab. No Life Needed.

By Brian Koberlein - September 25, 2024 11:24 AM UTC | Astrobiology
Astrobiologists continue to search for their ideal biosignatures. A chemical or collection of chemicals that would give a clear indication of life on an exoplanet. The problem is that natural processes can produce all the same chemicals that life can generate. Now, researchers have produced dimethyl sulfide in the lab, a chemical made by marine microbes. They used light and gases found in many planetary atmospheres. The search for biosignatures continues.
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Those Aren't Dyson Spheres, They're HotDOGs

By Brian Koberlein - September 23, 2024 10:23 AM UTC | Site News
Earlier this year, researchers claimed that they had found infrared signatures for candidate Dyson Sphere megastructures in archival WISE data. Astronomers were skeptical, suggesting that these objects might just be stars visually close to highly luminous "Hot Dust-Obscured Galaxies (HotDOGS)." The number of candidates matches the expected frequency of these chance alignments. This new paper puts a limit on the number of Dyson Spheres in our galactic neighborhood.
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Researchers Mimic Extracting Energy From Black Holes in the Lab

By Brian Koberlein - September 22, 2024 11:38 AM UTC | Black Holes
As black holes spin, they drag space-time along with them, and scientists have proposed that this could be a source of energy for an advanced civilization, harvesting momentum from material ejected from this twisting spacetime. The concept has been generalized, and it's theoretically possible to extract energy from anything spinning. Now, researchers have mimicked the process in the lab, beaming electromagnetic waves at a spinning object and extracting energy.
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Could Stars Hotter Than the Sun Still Support Life?

By Brian Koberlein - September 20, 2024 11:22 AM UTC | Astrobiology
Astronomers have several classifications for stars: the Sun is a G-type star. As you go up the list, the next hotter stars are the F-type, with surface temperatures in the range of 6200–7200 K. Could these stars have habitable zones where planets might support life? According to a new study, there have already been planets discovered within the habitable zones of F-type stars, which also lie outside the region where there is too much ultraviolet radiation.
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Exoplanets Could be Hiding Their Atmospheres

By Brian Koberlein - September 19, 2024 11:02 AM UTC | Exoplanets
One of the most intriguing planetary systems is TRAPPIST-1, with several Earth-sized worlds orbiting a red dwarf star, and astronomers have already scanned planets to search for evidence of an atmosphere. The first two worlds appear to be airless super-mercuries, and the hope lies on the next few planets, which orbit in the star's habitable zone. But what if the planets are hiding their atmospheres? A new paper suggests that night-side clouds can mimic an airless world.
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