Black Hole Picture Revealed for the First Time


Astronomers introduced on Wednesday that finally they’d seen the unseeable: a black gap, a cosmic abyss so deep and dense that not even mild can escape it.

“We’ve exposed a part of our universe we’ve never seen before,” stated Shep Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics, and director of the effort to seize the picture, throughout a Wednesday information convention in Washington, D.C.

The picture, of a lopsided ring of sunshine surrounding a darkish circle deep in the coronary heart of the galaxy generally known as Messier 87, some 55 million light-years away from right here, resembled the Eye of Sauron, a reminder but once more of the energy and malevolence of nature. It is a smoke ring framing a one-way portal to eternity.

To seize the picture, astronomers reached throughout intergalactic area to an enormous galaxy generally known as Messier 87, in the constellation Virgo. There, a black gap about seven billion occasions extra huge than the solar is unleashing a violent jet of vitality some 5,000 light-years into area.

[Sign up to get reminders for space and astronomy events on your calendar.]

The image offered a final, ringing affirmation of an idea so disturbing that even Einstein, from whose equations black holes emerged, was loath to accept it. If too much matter is crammed into one place, the cumulative force of gravity becomes overwhelming, and the place becomes an eternal trap, a black hole. Here, according to Einstein’s theory, matter, space and time come to an end and vanish like a dream.

On Wednesday morning that dark vision became a visceral reality. When the image was put up on the screen in Washington, cheers and gasps, followed by applause, broke out.

The image emerged from two years of computer analysis of observations from a network of radio antennas called the Event Horizon Telescope. In all, eight radio observatories on six mountains and four continents observed the galaxy in Virgo on and off for 10 days in April 2017.

The telescope array also monitored a dim source of radio noise called Sagittarius A* (pronounced Sagittarius A-star), at the heart of our Milky Way galaxy. There, 26,000 light-years from Earth, and buried in the depths of interstellar dust and gas, another black hole, with a mass of 4.1 million suns, almost certainly lurks.

The network is named after the edge of a black hole, the point of no return; beyond the event horizon, not even light can escape the black hole’s gravitational pull.

For some years now, the scientific literature, news media and films such as “Interstellar” and the newly released “High Life” have featured remarkably sophisticated and highly academic computer simulations of black holes. But the real thing looked different. For starters, the black holes in movies typically are not surrounded by fiery accretion disks of swirling, doomed matter, as are the black holes in Virgo and Sagittarius.

Perhaps even more important, the images provide astrophysicists with the first look at the innards of a black hole. The energy within is thought to be powerful enough to power quasars and other violent phenomena from the nuclei of galaxies, including the jets of intense radiation that spew 5,000 light-years from the galaxy M87.

As hot, dense gas swirls around the black hole, like water headed down a drain, the intense pressures and magnetic fields cause energy to squirt from either side. As a paradoxical result, supermassive black holes, which lurk in the centers of galaxies, can be the most luminous objects in the universe.

To Einstein’s surprise, the equations indicated that when too much matter or energy was concentrated in one place, space-time could collapse, trapping matter and light in perpetuity.

Einstein disliked that idea, but the consensus today is that the universe is speckled with black holes waiting for something to fall in.

Since then, other collisions have been recorded, and black holes have become so humdrum that astronomers no longer bother sending out news releases about them.

Now the reality has a face.

The proof that these objects are really black holes would be to find that the darkness at the heart of Virgo was smaller than the mathematical predictions for a black hole. But the more astronomers narrowed it down, the harder they had to work.

Interstellar space is filled with charged particles such as electrons and protons; these scattered the radio waves emanating from the black hole into a blur that obscured details of the source. “It’s like looking through frosted glass,” said Dr. Doeleman, director of the Event Horizon Telescope..

To penetrate the haze and see deeper into the shadows of Virgo, astronomers needed to be able to tune their radio telescope to shorter wavelengths. And they needed a bigger telescope. The bigger the antenna, the higher the resolution, or magnification, it can achieve.

Enter the Event Horizon Telescope, named for a black hole’s point of no return; whatever crosses the event horizon falls into blackness everlasting. The telescope was the dream-child of Dr. Doeleman, who was inspired to study black holes by examining the mysterious activity in the centers of violent radio galaxies such as M87.

By combining data from radio telescopes as far apart as the South Pole, France, Chile and Hawaii, using a technique called very long baseline interferometry, Dr. Doeleman and his colleagues created a telescope as big as Earth itself, with the power to resolve details as small as an orange on the lunar surface.

The data from the South Pole could not arrive before December 2017, Dr. Doeleman said, “because it was Antarctic winter, when nothing could go in or out.”

Last year the team divided into four groups to assemble images from the data dump. To stay objective and guard against bias, the teams had no contact with each other, Dr. Doeleman said.

In the meantime, the telescope kept growing. In April 2018, a telescope in Greenland was added to the collaboration. Another observation run was made of the Milky Way and M87, and captured twice the amount of data gathered in 2017.

“We’ve hitched our wagon to a bandwidth rocket,” Dr. Doeleman said last week. The new observations weren’t included in Wednesday’s reveal, but they will allow the astronomers to check the 2017 results and to track changes in the black holes as the years go by.

“The plan is to carry out these observations indefinitely,” said Dr. Doeleman, embarking on his new career as a tamer of extragalactic beasts, “and see how things change.



Source link Nytimes.com

Leave a Reply

Your email address will not be published. Required fields are marked *