Researchers Look Into a Black Hole (But Does the Black Hole Look Back?)

By Eliza Strickland | September 3, 2008 8:55 pm

black hole milky wayResearchers have gotten the closest look yet at the supermassive black hole that is believed to lurk in the center of the Milky Way, using radio telescopes to peer through the cosmic dust. Lead astronomer Sheperd Doeleman says: “One of the problems with looking at this particular source is that we have to look through our galaxy. It’s a blessing that it’s this close, but it’s a curse because it’s obscured by gas and dust” [].

Black holes can’t be directly observed, because their gravitational pull is so strong that nothing, not even visible light, can escape. To study our local gravitational monster, researchers homed in on Sagittarius A*, the bright radio-emitting body thought to mark the position of the black hole. Because Sagittarius A* is likely fueled by the black hole’s activity, a better look at the radio-emitting body can provide more details about the black hole [Science News].

Researchers have known that Sagittarius A* emits radio waves for some time, but hadn’t known much else about the enigmatic radiation source. Based on the new findings, published in the journal Nature [subscription required], they’ve now concluded that the source of the radiation likely originates in either a disk of matter swirling in toward the black hole, or a high-speed jet of matter being ejected by the black hole. Future investigations will help answer the question of what, precisely, they are seeing: a glowing corona around the black hole, an orbiting “hot spot,” or a jet of material [Telegraph].

To get an accurate image of this distant object, researchers combined observations from radio telescopes in Arizona, California, and Hawaii to create a “virtual telescope” with a virtual dish about 2,800 miles in diameter. The resulting level of accuracy at such a distance is over 1000 times more precise than we can get from the Hubble, and is the equivalent of being able to pick out a baseball sitting on the lunar surface from Earth [Ars Technica].

Image: S. Doeleman, M. Weiss/CXC, S. Noble, C. Gammie, NASA

  • ginsberg simjah

    Please explain: how can a high-speed jet of matter be ejected from a black hole if not even visible light can escape its gravitational pull?

  • Eliza Strickland

    Thanks for asking — you’re right, that wasn’t clear.

    According to astrophysicists, some supermassive black holes are surrounded by twisted magnetic fields that interact with clouds of ionized gas, called plasma, and send jets of this matter outward. The plasma is outside the black hole’s event horizon (the boundary within which nothing can escape), and can therefore be flung outwards through the cosmos.

  • dylan daniel

    wow that was cool but i dont think that was a black hole it did not look like on ps. type back and tell me if it was a real black hole bye

  • Dante Archibold

    It sounds like you’re creating problems yourself by attempting to solve this problem rather then investigating why their problem in the beginning of the process.


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles covering the day's most compelling topics.

See More

Collapse bottom bar