So far, our Milky Way Galaxy has only had close calls from gamma ray explosions so large, scientists have suggested, that if they occurred within our galaxy they could potentially trigger mass extinctions on Earth. In 2014, telescopes around the world pointed to our neighboring Andromeda galaxy (above) looking in all wavelengths of light to learn more about a gamma ray burst reported by NASA’s Swift satellite thought to be an explosion from the collision of two neutron stars–the dead cores of massive stars, with the mass of our Sun crushed into the size of a small city.
Welcome to this week’s fix of news of space and science –a random journey from Planet Earth through the Cosmos– that has the capacity to provide clues to our existence and add a much needed cosmic perspective in our current epoch.
One early result of the ongoing Dark Energy Survey is the previously untold story revealed by old, giant RR Lyrae pulsating stars, which tell scientists about the region of space beyond the edge of our Milky Way. In this area nearly devoid of stars–the motion of the RR Lyrae stars hints at the presence of an enormous halo of invisible dark matter, which may provide clues to how our galaxy evolved over the last 12 billion years.
In the Milky Way Galaxy, about three-fourths of the stars are M dwarfs, and the proportion is even higher in elliptical galaxies. But there’s a deadly catch. New research indicates orbiting close to these low-mass stars, prime targets for astronomers in the search for extraterrestrial life, may have lost their window of opportunity at hosting life because of intense heat during their formative years. M dwarfs, also known as red dwarfs, are the smallest type of hydrogen-burning star and are the most common stars and the coolest main-sequence stars in the universe.
Your weekly fix of news of space and science –a random journey from Planet Earth through the Cosmos– that has the capacity to provide clues to our existence and add a much needed cosmic perspective in our current epoch.
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“Planet Earth Report” provides descriptive links to headline news by leading science journalists about the extraordinary discoveries, technology, people, and events changing our knowledge of Planet Earth and the future of the human species.
The story: In April of 2019, Space Telescope Science Institute astronomer Marc Postman said that when he first first saw the Hubble image of the monster elliptical galaxy galaxy in the Abell 2261 galaxy cluster with a core bigger and brighter than any seen before, he knew immediately that something was odd, that its central core embraced a mystery never before seen. Spanning a little over one million light-years, the galaxy is about ten times the diameter of our own, and itself massive, Milky Way galaxy.
