Although black holes are notoriously dark objects, astronomers at Stanford University have just spotted a strange light coming from the far side of one of them.
An unprecedented observation
The gravitational pull of a black hole is so powerful that even light cannot escape from it. This of course makes these strange objects invisible, but it turns out that the light produced around them can reveal their presence. When these cosmic monsters suck up dust and gases, the resulting intense energy heats these materials to incredible temperatures, creating a highly magnetized plasma that glows brightly. Thus, a black hole appears as a circular silhouette on this luminous disc.
Sometimes X-ray flashes can be seen emanating from the disc. In the extreme environment of the black hole, the plasma’s magnetic field can twist and arch, eventually shattering and producing high-energy electrons. These in turn generate X-ray flares.
In this new study published in the journal Nature, the researchers began by studying the cause of the radiation, detected around a supermassive black hole located some 800 million light years away. In doing so, they noticed something new: small flashes of X-rays occasionally followed the main ones, at different wavelengths. Depending on the model, these later flashes were the same x-ray shards that were reflected from the back of the drive. This is the first time that astronomers have seen light emanating from the far side of a black hole.
“This black hole distorts space, bends light and twists the magnetic fields around it”
« Any light that enters this black hole does not come out, so we shouldn’t be able to see anything behind it. “, Explain Dan Wilkins, co-author of the study. ” The reason we can see this is because this black hole distorts space, bends light, and twists magnetic fields around it.. »
Such a phenomenon is known as the gravitational lens, where a large enough mass can deform the surrounding space-time web. This has the effect of bending the path of light from distant objects, such as stars, quasars, and galaxies, appearing in different parts of the sky. Sometimes the light is even split, so that it appears in two places simultaneously, or events like supernovas occur at different times.
According to the team, the next generation of x-ray telescopes should be able to pick up x-rays from black holes with greater resolution, which should help shed light on the mysteries surrounding them.