JWST is the Perfect Machine to Resolve the Hubble Tension

By Brian Koberlein - August 04, 2023 12:31 PM UTC | Cosmology
Over the last decade, various measurements have disagreed over the rate that the Universe is expanding. Astronomers use Cepheid variables as standard candles to measure relatively nearby galaxies and then use them to calibrate more distant candles like Type 1a supernovae. The most accurate measurements have been done with the Hubble Space Telescope, but a new survey of 330 Cepheid variables has been done with JWST, narrowing down the error bars even more and building a perfect distance ladder to Type 1a supernovae.
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Does the Milky Way's Supermassive Black Hole Have a Companion?

By Brian Koberlein - August 03, 2023 07:56 AM UTC | Milky Way
Astronomers have found stellar mass and supermassive black holes, but they're still on the hunt for an intermediate size; black holes with thousands of times the mass of the Sun. One natural place to look is at the heart of the Milky Way, near our galaxy's supermassive black hole. Researchers have examined the region around the galactic core and the movement of stars whipping around the central black hole. Although they didn't find evidence for a companion black hole, they've set size constraints on what could be there.
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Euclid Reaches L2, Shares its First Test Image

By Brian Koberlein - August 02, 2023 10:08 AM UTC | Missions
ESA's Euclid mission has made the journey through space to reach the Earth-Sun L2 Lagrange Point. The two instruments on board have come online and taken their first images of the cosmos. The left side of the image was taken by the VISible instrument (VIS), which will help astronomers study the shapes of billions of galaxies. The right side of the image was taken with the Near-Infrared Spectrometer and Photometer, which allows astronomers to measure the brightness and color of galaxies. Astronomers will use these instruments to make the most comprehensive 3D map of the Universe, hunting for dark matter and energy.
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What Does 60 Years of Silence Tell Us About the Search for Extraterrestrials?

By Brian Koberlein - August 01, 2023 10:41 AM UTC | Astrobiology
Astronomers have only been scanning the skies for a signal from extraterrestrial civilizations for about 60 years. Although no signal has been found, a new study suggests that this lack of detection can help us predict what the future holds for SETI. According to their analysis, this means there's a 50% probability that Earth won't detect signals for the next 60 to 1800 years.
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