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Special Report

First Black Hole Photograph

Professor David Helfand / Columbia University


Last week, for the first time ever, astronomers have captured an image of the supermassive black hole at the center of our galaxy.  Black holes don’t emit light, but the image shows its shadow surrounded by a bright ring – with a mass of roughly 4 million times the sun, the black hole’s immense gravitational pull is strong enough to bend even light around it, forming the ring captured in the image.  Columbia University Professor David Helfand’s Special Report explains in more detail, from Isacc Newton, to Albert Einstein, to last week’s photo.

David Helfand

Columbia University

David Helfand has been a Professor of Astronomy at Columbia University for 42 years, where he served as chair of the Department for nearly half that time. He is also the former President of the American Astronomical Society and of Quest University Canada, and currently serves as Chair of the American Institute of Physics. Professor Helfand has received the Columbia Presidential Teaching Award and the Great Teacher Award from the Society of Columbia Graduates. He is the author of A Survival Guide to the Misinformation Age.

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