A double distorted binary black hole world

Madrid, 16 (Europe Press)

Black holes orbiting millions of times the mass of the sun performing a “double ballet” in NASA’s new visualization.

(Https://www.youtube.com/watch) describe the movie?

When viewed up close the orbital plane, each accretion disk has a distinct double-grooved appearance. But when one passes in front of the other, the black hole’s gravitational pull in front turns the pair into a series of rapidly changing arcs. This distortion occurs when the light from the two discs travels through the fabric of time and space near the black hole.

“We saw two giant black holes, one bigger with 200 million solar masses and the smaller one with half its weight,” said Jeremy Schnittman, an astrophysicist at NASA’s Goddard Space Flight Center, who created the visualization. “This is the kind of black hole binary system that we believe both members can sustain a cumulative disk that lasts for millions of years.”

The accumulated discs are of different colors, red and blue, to make tracking light sources easier, but their selection also reflects reality. The hotter gas emits light closer to the blue end of the spectrum, and the material orbiting the smaller black hole is exposed to a stronger gravitational effect resulting in higher temperatures. For this block, the two accretion disks will emit most of their light in UV light, and the blue disc will reach a slightly higher temperature.

Visualizations like these help scientists imagine the consequences of the funhouse mirror’s extreme gravitational pull. The new video is duplicated from an earlier video produced by Schnittmann and shows a black hole from a different angle.

When viewed almost from the rim, the Accumulation Disc appears brighter on one side. Gravitational distortion changes the path of light coming from different parts of the disc, resulting in a distorted image. The rapid movement of gas near the black hole changes the luminosity of the disc through a phenomenon called Doppler thrust, an effect of Einstein’s theory of relativity which illuminates the side that is pointing at the viewer and dims the rotating side.

The visualization also shows a more subtle phenomenon called relative slope. Black holes appear smaller as they approach the observer and get bigger as they move further away.

This effect disappears when looking at the system from above, but new features appear. The two black holes produce tiny images of their counterparts rotating in each orbit. Taking a closer look, it’s clear that these photos are actually an edge view. To produce it, the light from a black hole has to be directed 90 degrees, which means we are looking at a black hole from two different perspectives, face and edge, at the same time.

“One of the surprising aspects of this new offering is the similar nature of the images produced by gravitational lenses,” explains Schnittmann. “Zooming in on each black hole reveals many partner images that are getting increasingly distorted.”

Schnittmann created the visualization by calculating the paths that light rays travel from the accretion disk as they move through the curved spacetime around the black hole.

On modern desktop computers, the calculations required to create a film frame will take about a decade. So Schnittman teamed up with Goddard data scientist Brian Powell to use the Discover supercomputer at NASA’s Climate Simulation Center. With only 2% of the 129,000 Discover processors, this calculation takes about a day.

In the not too distant future, astronomers hope to detect the gravitational waves (ripples in spacetime) generated by the presence of two supermassive black holes in a system very similar to what Schnittmann describes as spirals and fuses.

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