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What happens to space time when cosmic objects collide?

Everything we can observe in the Universe takes place in four dimensions—the three dimensions of space and the dimension of time. This basic system, known as spacetime, can distort in the presence of massive astronomical objects, bending light and even affecting time.

Our Work

1x10-21 meters
Size of the average gravitational wave

The detection of gravitational waves was a testament to incredible engineering and the power of the theory of general relativity. But it also showed what was possible when the astronomical community banded together. Within hours of the August 17, 2017 gravitational wave event, many major observatories were looking for the optical counterpart, with over 70 eventually participating. Since the event occured in the Southern Hemisphere, only certain telescopes could observe that region of the sky.

A few hours after the gravitational wave detection, as night set in Chile, CFA astronomers used the powerful Dark Energy Camera on the Blanco telescope to search the region of sky from which the gravitational waves emanated. In less than an hour they located a new source of visible light in the galaxy NGC 4993.

NASA’s Chandra X-ray Observatory tried observing the optical counterpart two days after gravitational waves detected but with no luck. Undeterred, Chandra observed again after another week and discovered X-rays right where they should be.

But the delay was curious. CFA scientists determined, using radio observations with the Very Large Array in New Mexico, that the collision blasted a narrow jet of high energy radiation about 30 degrees away from us. It was only when this energy heated the surrounding medium, around nine days after the collision, that Chandra was able to detect X-rays.

The discovery of a electromagnetic event coupled with a gravitational wave event is a first for “multi-messenger” astronomy. By combining the two messengers, we are learning more about the source than we ever would separately.