Learning about weird star corpses from the way they shake

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‘Dwarfquakes’ Reveal the Future of Our Universe

Dying stars were an enigma—until an astronomer measured seismic shifts on them, giving us clues about the sun’s future and the expansion rate of the universe.

For The Daily Beast:

White dwarfs—the hot, burned-out remains of ordinary stars—are very common in the universe, and weird. (Our very own sun will become a white dwarf in a few billion years, too.) Imagine something the size of Earth, but 300,000 times more massive, glowing white-hot and bright enough to be seen far away despite its tiny size.

“It’s just a pixel of light,” Noemi Giammichele, an astronomer at the University of Toulouse, told The Daily Beast. “I find it really amazing all the information we can gather just from that one tiny dot.”

Made of pure carbon and oxygen, with only a thin haze of other atoms acting as its atmosphere, white dwarfs certainly aren’t like anything we can make in a lab on Earth. But Giammichele used seismology to measure “dwarfquakes” to not only understand the internal structure of these white dwarfs but also the future expansion rate of our universe.

[Read the rest at The Daily Beast]

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The ALMA telescopes found a spiral pattern surrounding the dying star R Sculpturis.

Though it may seem sad on the surface, the death of a star is a beautiful thing—and an important precursor to the birth of new stars and planets. The Atacama Large Millimeter Array (ALMA) in Chile has provided a breathtaking view of a star nearing the end of its life. One unexpected feature was a lovely spiral pattern that probably indicates the presence of a hidden companion.

While earlier observations showed a thin spherical shell of gas perfectly centered on R Sculptoris, the ALMA data revealed unexpected structure inside. The details included clumps in the gas shell and a winding spiral pattern, as seen in the image above. Additionally, the amount of mass contained in the surrounding matter is approximately three times what was estimated from earlier observations and models of similar stars. [Read more….]

The beautiful spiral of a dying star