The brightest pulsar found thanks to “sunglasses”

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ONE pulsarit’s a bit like a lighthouse guiding astronomers to the extent ofUniverse. ONE star pulsating that emits waves radio at such a regular rate that scientists first believed in … signals sent by extraterrestrial civilizations. Astronomers know that now pulsar is none other than neutron stars, what’s left of massive, incredibly dense stars spinning very fast. In just a second. Even smaller.

The first pulsar was observed in 1967 near Cambridge (UK). Since then, more than 3,000 other pulsars have been discovered. Most in ours Galaxy. But about thirty anyway, in our nearest neighbor, the Large Magellanic Cloud. And today it is thanks to a new technique that astronomers from Commonwealth Scientific and Industrial Research Organization (Csiro) has just made an amazing discovery there. This bright spot, which scientists until then took for a distant galaxy, would in fact be just another pulsar in the heart of the Great Magellanic Cloud. And not just any pulsar. The one they called PSR J0523-7125 would be the brightest pulsar ever observed outside The Milky Way. Perhaps even the most luminous pulsar of all!

To understand how such an object could have passed under the radar so far, it is necessary to know that in order to find pulsars classically, astronomers search for the characteristic repetitive signals that these astonishing objects leave in the data from radio telescopes. The method is effective. Most of the time. Because it tends not to detect pulsars beyond the usual. Pulsars that are too fast or too slow. But also those if pulse » is scattered.

Still many pulsars to discover

To discover this type of pulsars, the researchers imagined that they could rely on a different property of pulsars. Their rays can actually be very circularly polarized. Understand that the electric field of their light waves assumes a circular motion as the waves travel through space. And such signals are rare.

But just thatAustralian Square Kilometer Array PathfinderAustralian Square Kilometer (Askap) Radio Telescope Array, has a kind sunglasses » allows him to capture this lightpolarized. And it was a student who finally in the data from the instrument spotted a circularly polarized object in a place where there was no known pulsar.

Observations of the region with the help of others telescopes made it possible to remove all assumptions. And the MeerKAT radio telescope – also equipped with the famous one “glass of sun » – from the South African Radio Astronomy Observatory confirmed it. It is truly a pulsar that Askap has thus discovered. A pulsar ten times brighter than any other pulsar detected so far outside The Milky Wayto about 160,000light yearsof our earth. Maybe even justbrighternever observed.

Thanks to this new technique, astronomers now hope to discover other extragalactic pulsars. And why not, pulsars located beyond the great Magellanic cloud. Observations that will help them better understand the processes that are still hidden behind these extreme objects.

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