Tech

What is this “black widow” in our sky?

When I tell you black widow, you necessarily think of this spider with disastrous habits. But know that the little beast isn’t the only one to earn this moniker. A few “black widows” are also hiding in our air. Astronomers also believe they have unmasked a new one, with somewhat surprising behavior.

The Black Widowfor biologists it is a spider a little special. Because she can let go of one venom mortal for men, first. But also because the females of the black widow have a habit of devouring the males, smaller than them, after theto link† And it’s this funny trait that some people also deserve their nickname binary systems bystars† Systems consisting of a pulsar – the collapsed remains of a massive star, a neutron star in very fast rotation on its own – what, for gravity, gradually devouring a smaller companion star. earn extra expensive of life.

By astronomers of Massachusetts Institute of Technology (MIT, USA) have just observed what looks like a new one of these “black widows”† at 3,000 light years of our earth approximately. A surprising system in more ways than one. First, because the ZTF J1406+1222 was detected in visible light. Making itself known to researchers through the characteristic and spectacular blinking of the pulsar’s companion star. Classically, it is rather the gamma and X-rays emitted by the pulsar that warn astronomers

Another peculiarity of ZTF J1406+1222 revealed by a Brightness varying by a factor of 13: sa turnaround time extremely short. The shortest ever seen elsewhere. Right away pulsar and a star that orbits each other in just… 62 minutes!

A ” Black Widow “ or maybe something else

And the ZTF J1406+1222 does not stop there. This is funny ” Black Widow “ seems to be keeping a third star under his wing. Further away. It completes its round in 10,000 years. A configuration that raises questions for astronomers.

To explain, they believe that, as is the case with most “black widows” known – about two dozen so far – this triple system was formed in a globular cluster† Long before our Sun begins to shine. Drifting to the center of the Milky Waythe latter may have been disturbed by the gravitational force exerted by the supermassive black hole who lives there. Disturbed enough to burst while leaving ZTF J1406+1222 intact.

But astronomers at MIT warn us. Pending new observations, it remains wiser to continue to consider this triple system as a candidate ” Black Widow “† After all, he hasn’t revealed one (yet)emissions gamma or x-rays features of the presence of a pulsar. All the researchers are sure of is that they’ve detected a star with one side much hotter than the other — the one that may be receiving the pulsar’s constant radiation — and orbiting something in just over an hour. . So if all indications are that it is indeed the companion of a pulsar and a ” Black Widow “it can also be something… completely new!

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