Feb 26, 2020 - Science

Astronomers find double star system that keeps changing its behavior


A large cluster of stars 19,000 light-years from Earth harbors something strange: Within the cluster, a neutron star left over after a supernova explosion orbits a star not too different from our Sun.

The big picture: The Chandra observatory has been observing that star system — known as Terzan 5 CX1 — for more than a decade, and in that time, Terzan 5 CX1 has gone from looking like one type of star system to another and back again.

  • As that neutron star orbits the other in the pair, its immense gravity pulls material from the companion star, forming a disk around the neutron star.
  • All that material falling in on the neutron star makes it spin quickly, blowing away any extra material encircling the star and transforming it into what's known as a millisecond pulsar.

Yes, but: Chandra found this star system has gone from behaving like a more typical binary to a millisecond pulsar and then back again.

  • It's not yet clear why the pair has done this dance multiple times, but scientists expect this is a phase in the evolution of these types of star systems.

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A glowing cloud in deep space could unlock how massive stars grow

Photo: ESA/Hubble/NASA/I. Stephens

A pink stellar cloud not far from the Tarantula Nebula 160,000 light-years away is demonstrating how extremely massive stars form.

The state of play: The cloud — known as LHA 120-N 150 — contains dozens of newly forming massive stars and clumps of dust that could help scientists learn more about whether large stars form in dense clusters or in isolation, according to ESA.

Go deeperArrowMar 24, 2020 - Science

NASA spacecraft snaps a fortuitous shot of a black hole 30,000 light-years away

Gif: NASA/Goddard/University of Arizona/MIT/Harvard

Sometimes the best photos are taken by accident. NASA's OSIRIS-REx spacecraft was exploring an asteroid not far from Earth when it unexpectedly caught sight of a black hole 30,000 light-years away.

What they found: OSIRIS-REx detected the black hole using an instrument designed to measure the effect solar particles are having on its target asteroid, Bennu.

Go deeperArrowMar 3, 2020 - Science

AOC says she will support Biden if he wins Democratic nomination

Photo: Joseph Prezioso/AFP via Getty Images

Rep. Alexandria Ocasio-Cortez (D-N.Y.) said Thursday she will support Joe Biden if he wins the Democratic presidential nomination during an appearance on NBC's "Late Night with Seth Meyers."

"I've said throughout this entire process that what is so important that we ultimately unite behind who that Democratic nominee is. I think it's a two-way street. I've been concerned by some folks that say if Bernie's the nominee, they won't support him and the other way around."

The big picture: Ocasio-Cortez, one of the most popular figures on the progressive left, is a key surrogate for Bernie Sanders — and her star power on the trail has triggered speculation that she might seek a presidential bid of her own in 2024.