In the end, the images each team produced were very similar, suggesting that the observations are robust and that the final snapshot is the most accurate possible. Then, because combining observations from different observatories is no simple task, four teams processed the data independently, using different algorithms and testing it against different models.

“It’s equivalent to 5,000 years of MP3 files, or according to one study I read, the entire selfie collection over a lifetime of 40,000 people.” “Five petabytes is a lot of data,” says team member Dan Marrone of the University of Arizona. During that observing run, which also included targets other than M87, the team gathered so much data-five petabytes-that the only reasonable way to transfer it was by shipping actual hard drives, rather than sending it digitally. “It’s about the same size as if you were trying to take a picture of an orange on the moon.”įor several days, the team observed M87 in short radio wavelengths, because radio waves can pierce the murky shrouds of dust and gas surrounding galactic centers. “What we’re trying to image is really, really small on the sky,” says Caltech’s Katie Bouman, a member of the EHT imaging team. Functioning as one Earth-sized telescope, the network can resolve objects just one-ten thousandth the angular size of what Hubble can see. In the end, six observatories in Mexico, Hawaii, Arizona, Chile, and Spain aimed their eyes into sky and stared at M87, which is the biggest galaxy in the center of the Virgo cluster. To resolve these supermassive black holes-which are tiny compared to their surrounding galaxies-the consortium needed to harness the power of radio telescopes all over the planet. Photograph courtesy NASA and the Hubble Heritage Team (STScI/AURA) With its relatively high brightness magnitude and at a distance of 28 million light-years from Earth, Messier 104, as Sombrero is more formally known, is easily viewed through a small telescope. Among the most memorable is this edge-on mosaic of the Sombrero galaxy. Over its lifetime, NASA's Hubble Space Telescope has captured many stunning images. When separate dishes simultaneously observe the same target, scientists can collate the observations and “see” an object as though they’re using one giant dish that spans the distance between those telescopes. Rather than being a single snapshot, like the many spectacular photos taken by the Hubble Space Telescope, the EHT‘s image is the product of a process called interferometry, which combines observations from multiple telescopes into one image.

Seeing into the heart of our galaxy turned out to be a bit more complicated than staring down the barrel of a black hole in the next galaxy cluster over, which is why M87’s portrait is out first. Because M87 is one of the nearest, biggest black holes, the team also decided to aim the telescope there, hoping to eventually compare the two bruisers. Called Sagittarius A*, that black hole is relatively puny compared to M87, containing the mass of just four million suns. The Event Horizon Telescope initially set out to snag an image of the supermassive black hole at the core of our galaxy, the Milky Way. Photograph by NASA and the Hubble Heritage Team (STScI/AURA) Orange on the moon In this Hubble image, the blue jet contrasts with the yellow glow from the combined light of M87's stars and star clusters. The center of M87 glows with a gargantuan cosmic searchlight: a black-hole-powered jet of subatomic particles traveling at nearly the speed of light. “Nature has conspired to let us see something we thought was invisible.” “It’s truly remarkable, it’s almost humbling in a certain way,” Doeleman says. The data also offer some hints about how some supermassive black holes manage to unleash gargantuan jets of particles traveling at near light-speed. One of the chief takeaways is a more direct calculation of the black hole’s mass, which tracks closely with estimates derived from the motion of orbiting stars. Six papers published today in the Astrophysical Journal Lettersdescribe the observational tour de force, the process of achieving it, and the details that the image reveals. “What you are seeing is evidence of an event horizon … we now have visual evidence of a black hole.” “We are delighted to be able to report to you today that we have seen what we thought was unseeable,” added project director Shep Doeleman of the Harvard-Smithsonian Institute for Astrophysics. “We’ve been studying black holes for so long that sometimes it’s easy to forget that none of us has ever seen one,” National Science Foundation director France Cordova said today during a press conference announcing the team’s achievement, held at the National Press Club in Washington, D.C.

First black hole image