Astronomers Will Soon Have the First-Ever Picture of a Black Hole

The center of the Milky Way galaxy, with the supermassive black hole Sagittarius A*, located in the middle, as captured in x-ray and infrared in this 2013 NASA photo.
The center of the Milky Way galaxy, with the supermassive black hole Sagittarius A*, located in the middle, as captured in x-ray and infrared in this 2013 NASA photo.
NASA/UMass/D.Wang et al., IR: NASA/STScI

It may not be the closest black hole to Earth, but it’s certainly the closest one that astronomers have labeled as "supermassive." Known as Sagittarius A* (pronounced “Sagittarius A-star”), the mysterious object, first detected in the 1970s, weighs as much as 4 million Suns. Formed by the collapse of large stars, most black holes aren't nearly that size.

Sagittarius A* sits at the very heart of the Milky Way galaxy, some 25,000 light-years from our solar system—but until now, we haven’t known much about it. Soon, however, thanks to a globe-spanning array of radio telescopes known as the Event Horizon Telescope, astronomers will have their closest ever look at this enigmatic object.

The Event Horizon Telescope, or EHT, is named for the infamous “point of no return” that marks the outer boundary of a black hole. (The gravity of a black hole is so strong that nothing can escape it, not even light—thus the name.) It incorporates huge, dish-shaped telescopes at six different sites on four continents, including Antarctica and Hawaii. The array recently completed its most ambitious observation so far, collecting data of Sagittarius A* over a 10-day period in mid-April.

“We’ve never had data of the quality that we’ve just taken,” Dan Marrone, an experimental astrophysicist at the University of Arizona, tells Mental Floss. When the data is eventually processed—sometime this fall at the earliest—astronomers will have their clearest picture yet of a black hole.

A VIEW OF THE EDGE

What that image will actually look like, however, is still very much up in the air. We know that black holes are typically surrounded by accretion disks—rings of dust and gas that swirl around the black hole, getting ever-hotter as the material approaches the black hole’s event horizon. The in-falling matter gets so hot that it emits radio waves and other radiation (which is how objects like Sagittarius A* were first detected). Accretion disks can also produce jets—streams of high-energy particles that get blasted out from the black hole at nearly the speed of light. And we know that the system’s intense gravity bends starlight as it passes near the black hole. “We might see a crescent, brightened on one side—or a bipolar, jet-like structure,” Marrone says. “We honestly don’t know.”

Standard optical telescopes—even those high above the Earth’s atmosphere, like Hubble—can tell us very little about objects like Sagittarius A* because there’s too much gas and dust between us and the galactic center for optical wavelengths to penetrate; it’s like trying to peer across San Francisco Bay on the foggiest day of the year.

But radio telescopes, taking advantage of the longer wavelengths of radio waves, can see through the murk. The best bet, astronomers have found, is to use telescopes sensitive to wavelengths of about 1 centimeter—longer than wavelengths of infrared light, but shorter than the waves that your car radio picks up.

Multiple radio telescopes, in different locations, can be made to work together even better, simulating a much larger instrument. This technique is known as VLBI, for Very Long Baseline Interferometry. The Atacama Large Millimeter-submillimeter Array, comprising 66 radio dishes in northern Chile, was recently added to the EHT array, greatly boosting the overall sensitivity; the South Pole Telescope was also added to the array in April. The project now involves 30 institutions in 12 countries.

“The Event Horizon Telescope is going to be zooming in, to right where the inner edge of the accretion disk is falling in to the black hole—right at the boundary between where the disk material ends and the black hole starts,” radio astronomer Joseph Lazio of NASA’s Jet Propulsion Laboratory tells Mental Floss.

A BLACK HOLE WITHOUT MUCH OF AN APPETITE

Of course, we can never see past the event horizon—whatever’s on the other side remains forever beyond our reach. But with the resolving power of the EHT, astronomers will have their closest look yet at the region immediately outside it.

The EHT’s resolving power will be so crucial because, despite Sagittarius A*’s heft, it’s not very large in terms of size. Its event horizon is believed to span just about 15 million miles—less than 20 times the diameter of the Sun.

And in spite of the public perception of black holes as “cosmic vacuum cleaners” that suck up everything in sight, Sagittarius A* is actually not much of an eater. “It’s on a starvation diet,” Marrone jokes. “We don’t know of another black hole that’s eating so slowly, relative to its weight.”

Another target for the EHT will be the black hole in the center of a galaxy known as M87. This ginormous black hole is 1000 times farther away than Sagittarius A*, but it’s also 1000 times more massive; it’s so big that its gravity anchors an entire cluster of galaxies, known as the Virgo Cluster. And it has enormous jets shooting out of its accretion disk—something that astronomers are anxious to get a closer look at.

Beyond simply imaging these giant black holes, the EHT may shed some light on the complex relationship between supermassive black holes and the galaxies that harbor them. Surveys using X-ray telescopes suggest that these overweight black holes are common; they’re believed to lurk in the hearts of most galaxies. But did the galaxies evolve first, and then the black holes—or was it the other way around?

WHAT CAME FIRST, THE BLACK HOLE OR THE GALAXY?

“There’s a very strong correlation between the properties of these supermassive black holes and the properties of their host galaxies,” David Spergel, a Princeton astrophysicist and director of the Center for Computational Astrophysics, tells Mental Floss. “So they’re linked together—but this is a chicken-and-egg question that we don’t know the answer to.”

Another motivation for studying black holes is to determine whether Einstein’s theory of gravity, known as general relativity, correctly predicts the observed physics. The theory, which turned 100 last year, has so far passed every test thrown at it—but it has yet to be tested in the exotic environment adjacent to a black hole event horizon, with its ultra-strong gravitational field. “You’re probing a new regime—and whenever you’re in a new regime, you could be in for a surprise,” Spergel says.

The astronomers working on the EHT won’t see the fruits of their labors right away: Each of the facilities in the array recorded about 500 terabytes of data during this spring’s observing run—far too much to be conveniently sent over the internet. So the data is being sent the old-fashioned way, by shipping bulky drives via FedEx to the EHT’s two processing centers, located in Westford, Massachusetts and in Bonn, Germany. (That doesn’t include the disks from the South Pole Telescope; they’ll be shipped later in the year, when planes can access the site after the Antarctic winter.) Then the data needs to be processed, which will take some six to eight months.

Asked if he was feeling tense, Marrone replied that “anticipation” was a better word; after all the testing he and his colleagues have done, he’s pretty confident that the EHT has delivered the goods. “I’d like to know what we’ve got in those data,” he said. “But it’s going to be a long wait.”

Turn Your LEGO Bricks Into a Drone With the Flybrix Drone Kit

Flyxbrix/FatBrain
Flyxbrix/FatBrain

Now more than ever, it’s important to have a good hobby. Of course, a lot of people—maybe even you—have been obsessed with learning TikTok dances and baking sourdough bread for the last few months, but those hobbies can wear out their welcome pretty fast. So if you or someone you love is looking for something that’s a little more intellectually stimulating, you need to check out the Flybrix LEGO drone kit from Fat Brain Toys.

What is a Flybrix LEGO Drone Kit?

The Flybrix drone kit lets you build your own drones out of LEGO bricks and fly them around your house using your smartphone as a remote control (via Bluetooth). The kit itself comes with absolutely everything you need to start flying almost immediately, including a bag of 56-plus LEGO bricks, a LEGO figure pilot, eight quick-connect motors, eight propellers, a propeller wrench, a pre-programmed Flybrix flight board PCB, a USB data cord, a LiPo battery, and a USB LiPo battery charger. All you’ll have to do is download the Flybrix Configuration Software, the Bluetooth Flight Control App, and access online instructions and tutorials.

Experiment with your own designs.

The Flybrix LEGO drone kit is specifically designed to promote exploration and experimentation. All the components are tough and can totally withstand a few crash landings, so you can build and rebuild your own drones until you come up with the perfect design. Then you can do it all again. Try different motor arrangements, add your own LEGO bricks, experiment with different shapes—this kit is a wannabe engineer’s dream.

For the more advanced STEM learners out there, Flybrix lets you experiment with coding and block-based coding. It uses an arduino-based hackable circuit board, and the Flybrix app has advanced features that let you try your hand at software design.

Who is the Flybrix LEGO Drone Kit for?

Flybrix is a really fun way to introduce a number of core STEM concepts, which makes it ideal for kids—and technically, that’s who it was designed for. But because engineering and coding can get a little complicated, the recommended age for independent experimentation is 13 and up. However, kids younger than 13 can certainly work on Flybrix drones with the help of their parents. In fact, it actually makes a fantastic family hobby.

Ready to start building your own LEGO drones? Click here to order your Flybrix kit today for $198.

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Barnard College’s Corpse Flower Just Bloomed for the First Time Ever—Watch It Here

This corpse flower is ready for her closeup.
This corpse flower is ready for her closeup.
Nicholas Gershberg/Barnard College

If someone’s talking about a corpse flower, or Amorphophallus titanum, there’s a good chance they’ll end up mentioning one or all of these characteristics: It’s phallic, it smells atrocious, and it might only bloom about once a decade.

Earlier this week, Barnard College’s corpse flower unfurled for the first time ever, and you can watch its slow progress in real time on the YouTube livestream below. This particular specimen was given to Barnard’s Arthur Ross Greenhouse by the Brooklyn Botanic Garden Horticulture Department in 2013, and it’s named “Berani,” after the Indonesian word for brave—a nod to the species’s native region of Sumatra, Indonesia.

In previous years, the greenhouse staff has watched the potato-like tuber sprout into a tall, leafy structure—each taller than the last, with the most recent one measuring about 12 feet—hoping that next time, they’d get to watch it blossom into a flower instead. When Berani began to shoot up again this spring, they noticed it looked different, and by the time it was nearly 3 feet tall, they could confirm that the swollen spathe would soon unsheath a beautiful, putrid flower.

Since the coronavirus pandemic prevented them from inviting the public to see Berani blossom in person, greenhouse administrator Nick Gershberg and his colleagues have documented the process on the greenhouse’s Instagram account (as well as the livestream), and they’re planning to release a time-lapse video soon.


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A post shared by The Arthur Ross Greenhouse (@barnardgreenhouse) on

Gershberg tells Mental Floss that the flower reached its peak on Sunday night, May 31, at which point it measured 72 inches tall and 44 inches wide. And, true to its reputation, the corpse flower filled the room with a heavy stench that initially smelled like a dead rat. As the flower heated itself up to a temperature about 12 degrees warmer than the room—a respiration process called thermogenesis—Gershberg detected other recognizable scents, including dead fish, Camembert cheese that’s been left out overnight, and the odor of slightly decayed lilies. After the flower’s temperature came back down, it settled into a much more pleasant smell: a freshly-gutted pumpkin.

The corpse flower gets its name because its odor is often compared to that of a corpse, but Gershberg’s experience suggests that the association might be more in our heads than anything else.

“It was only when I went on the mental expedition of happening upon [the smell] in a jungle and thinking, ‘Oh my god, that’s a dead body,’ that it was actually nauseating. At that point, it was very nauseating,” he explains. “But as soon as I stopped thinking about it as, like, ‘Oh this is a dead body, or maybe dead person, even,’ then it didn’t have that effect. So it was interesting to see how in the face of this extreme odor, so much of it was really psychological, as far as whether I thought it was a good smell or a bad smell.”

Since a corpse flower only blooms for about 48 hours, Berani will soon begin to wither, and it’ll eventually fall over and separate from its base. After the roots die, the only thing left will be what Gershberg describes as “a 40-pound, beach ball-sized potato.” The team will remove it from the pot, clean it, inspect it for any infections, replant it, and wait for the now-dormant tuber to send up a new leaf, which will likely happen sometime in the next three to six months.

barnard college corpse flower closeup
Berani is giving every glamorous red carpet gown a run for its money.
Nicholas Gershberg/Barnard College

According to Gershberg, the experience of seeing the corpse flower bloom in all its majestic glory fundamentally changes how you view its usual tuber and leaves.

“It’s like when you see someone do karaoke and you’re like, ‘My god, that person can really sing,’ and you never quite look at them the same way again,” he says. “You’re like, ‘There’s actually a superstar in that head of accounting over there.’”

To help them remember just how big of a superstar Berani really is—and give the public a chance to see it for themselves in the future—the Barnard team is hoping to preserve some of it as a flower pressing. While you’re waiting to see what that looks like, you can learn more about corpse flowers here.