There is a tiny, brilliant, photobombing magnetar in the supermassive black hole of our galaxy

A luminous magnetobot photobomb the supermassive black hole in the center of the Milky Way, thwarting astronomers' efforts to study the black hole – called Sagittarius A * – using X-ray telescopes.

SagA * is the supermassive black hole closest to the Earth. And although much smaller, quieter and more graded than the recently imaged black hole at the center of the Messier 87 galaxy, it still represents one of the best opportunities for astronomers to understand the behavior and interactions of black holes with their environment. But in 2013, a magnetar – an ultradense star (also called a neutron star) enveloped in powerful magnetic fields – between SagA * and the illuminated Earth, has since played out attempts to observe the black hole at the planet. using X-ray telescopes.

"We think that there may be a burst of the surface of the neutron star or a really violent event on the neutron star. which makes it very, very shiny and gradually fades over time, "said Daryl Haggard, a physicist at McGill University. in Montreal studying SagA * and the galactic center. [3 Huge Questions the Black Hole Image Didn’t Answer]

Magnetars are tiny objects, belonging to a class of stars of comparable size to that of the Isle of Manhattan. Before the little star lit up, she gave no sign of her presence.

In 2013, this changed. At the time, Haggard was part of a team that was observing SagA * using data from an X-ray telescope to see how the black hole would interact with G2, a large gaseous object that was to pass very close to the black hole. Black holes do not emit light, unlike hot orbiting gases that are just outside their niche. The surrounding SagA * cloud usually only glows faintly, but the researchers hoped that if G2 crossed it, interesting X-ray lightning would occur.

Then, on April 24, 2013, a surprising cascade of data began to arrive from their telescopes. The first telescope to notice this sudden change is Swift, an orbital telescope from NASA.

"We were watching the supermassive black hole, trying to grab a little signature in the x-ray wavelengths from that interaction, and then BANG, the magnetar went off," she said. at Live Science, applauding for insisting. .

There was a bright flash of X-rays. At first, astronomers thought they were observing new and unprecedented behavior of the black hole, possibly a massive eruption, Haggard said. Most X-ray observatories do not have the resolution to distinguish between two objects, especially when the magnetar burst so brightly.

The two objects are quite far apart from one another in the physical space, about 3.2 billion kilometers, one – third of a light – year. Telescopes regularly see other, nearer stars around the black hole as separate objects. But it turns out that SagA * and the magnetar (named SGR 1745-2900) are sloped so that, from the Earth's point of view, they overlap almost just 2.4 seconds arc in the sky . (The entire sky is about 1,296,000 seconds of arcs.)

Most X-ray observatories view them as a single object, said Haggard.

"At first, the great excitement was:" Holy Cow, SagA * went crazy! "It would have been the brightest light we've ever seen since the supermassive black hole," she said. declared, evoking the X-ray flare.

But on April 26, 2013, NuSTAR, another NASA orbital X-ray telescope, picked up something funny in the lighted area: a kind of ticking, a pulsating quality in the light, with spikes every 3.76 seconds. This is not the kind of behavior they expect from gas clouds around a black hole, even in its most excited state, Haggard said. [9 Ideas About Black Holes That Will Blow Your Mind]

Three days later, on April 29, the Chandra X-ray Observatory, the most powerful telescope of its kind in space, solved the image well enough for there to actually be two X-ray sources: the new bright and flickering light, and the relatively weaker glow of gas around a SagA * at rest.

As reported by a team of observers in The Astrophysical Journal in May of that year, this pulsation was characteristic of a bright spot located on a star that was spinning rapidly toward the Earth, at the way of an acceleration lighthouse. Astrophysicists understood that they saw a magnetar.

"According to your point of view, it was either a total pain or a completely impressive new discovery," Haggard said.

Over time, the glow of the magnetar has faded, but more slowly than usual. These days, says Haggard, the X-ray brightness is roughly equivalent to the glow of the hot gas surrounding the black hole, making it easier for Chandra to distinguish the two. Yet, she said, they look a bit like the two lights of a car so far apart that they have begun to blend into one. Even Chandra finds it hard to tell which X-ray photons come from hot gases around the black hole and those from the magnetar.

Haggard said that this kind of problem was typical of galactic center observers. There is a cloud of hot materials so dense and bright in the region, she said, that any observation requires careful sorting of good waste data. The magnetar has become an additional frustration for SagA * watchers.

Originally published on Science live.