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Dark matter dominates in nearby dwarf galaxy

Dark matter is called “dark” for a good reason. Although they outnumber particles of regular matter by more than a factor of 10, particles of dark matter are elusive. Now, by measuring the mass of a nearby dwarf galaxy called Triangulum II, astronomers believe they may have found the highest concentration of dark matter in any known galaxy.

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Visualising the Sun’s neighbourhood in 3-D

Astronomers have used modern techniques to create a 3-D visualisation of all of the O- and B-type stars within 500 parsecs (1,630 light-years) of the Sun using data from ESA’s Hipparcos satellite. This new visualisation uncovers evidence for new structures in the distribution of these nearby hot stars, and new and surprising theories of how those stars formed.

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Discovery measures “heartbeats” of a distant galaxy’s stars

In many ways stars are like living beings. They’re born; they live; they die. And they even have a heartbeat. Near the end of their lifetime they begin to pulsate, increasing and decreasing their brightness by a large amount every few hundred days. Using a novel technique, astronomers have detected thousands of stellar “pulses” in the galaxy Messier 87 (M87). Their measurements offer a new way of determining a galaxy’s age.

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NASA’s Fermi finds hints of gamma-ray cycle in active galaxy

Astronomers using data from NASA’s Fermi Gamma-ray Space Telescope have detected hints of periodic changes in the brightness of a so-called “active” galaxy, whose emissions are powered by a supersized black hole. If confirmed, the discovery would mark the first years-long cyclic gamma-ray emission ever detected from any galaxy, which could provide new insights into physical processes near the black hole.