Sequence of Hubble and Chandra Observations
(Credit: NASA/CXC/A. Jubett)
[Runtime: 25 seconds]



The sequence begins with a view of NGC 4993 from NASA's Hubble Space Telescope before zooming into GW170818. From there, the Chandra data from August 19 and then an additional observation on August 26 are shown. The change in X-ray brightness tells astronomers about the nature of this event, which involved the merger of two neutron stars. This discovery of detecting the aftermath of this gravitational wave event, the first to produce an electromagnetic signal of any type, represents the beginning of a new era in astrophysics.

Neutron Star Merger Animation
(Credit: NASA's Goddard Space Flight Center/CI Lab)
[Runtime: 41 seconds]



This animation captures phenomena observed over the course of nine days following the neutron star merger known as GW170817. They include gravitational waves (pale arcs), a near-light-speed jet that produced gamma rays (magenta), expanding debris from a kilonova that produced ultraviolet (violet), optical and infrared (blue-white to red) emission, and, once the jet directed toward us expanded into our view from Earth, X-rays (blue).

Short Video Interviews
(Credit: NASA/CXC/A. Jubett)
[Runtime: 04:24]

With closed-captions (at YouTube)

In these clips, four astronomers discuss the latest result in which NASA's Chandra X-ray Observatory, along with many other telescopes, detected light from a gravitational wave source for the first time. These scientists represent the many who worked very hard since the source's discovery on August 17, 2017, to make this result happen. This discovery is both historic and significant, and it represents a new era of astrophysics.

A Tour of GW170817
(Credit: NASA/CXC/A. Jubett)
[Runtime: 02:TBD]

With closed-captions (at YouTube)

Astronomers have used NASA's Chandra X-ray Observatory to make the first X-ray detection of a gravitational wave source. Chandra was one of multiple observatories to detect the aftermath of this gravitational wave event, the first to produce an electromagnetic signal of any type. This discovery represents the beginning of a new era in astrophysics.

The gravitational wave source, GW170817, was detected with the advanced Laser Interferometer Gravitational-Wave Observatory, or LIGO, at 8:41am EDT on Thursday August 17, 2017. Two seconds later NASA's Fermi Gamma-ray Burst Monitor detected a weak pulse of gamma rays. Later that morning, LIGO scientists announced that GW170817 had the characteristics of a merger of two neutron stars.

During the evening of August 17, multiple teams of astronomers using ground-based telescopes reported a detection of a new source of optical and infrared light in the galaxy NGC 4993, a galaxy located about 130 million light years from Earth.

Over the following two weeks, Chandra observed NGC 4993 and the source GW170817 four separate times. In the first observation on August 19th, no X-rays were detected at the location of GW170817. This observation was obtained remarkably quickly, only 2.3 days after the gravitational source was detected.

On August 26, Chandra observed GW170817 again and this time, X-rays were seen for the first time. This new X-ray source was located at the exact position of the optical and infrared source.

All of these pieces of information indicate that this event was produced by the merger of two neutron stars, which, in turn, set off a gamma-ray burst that produced a jet pointing away from Earth. The combination of gravitational wave signals with light detected by various telescopes including Chandra represents a new era in astrophysics.

A Quick Look at GW170817
(Credit: NASA/CXC/A. Jubett)
[Runtime: 01:06]

On August 17, 2017, scientists detected gravitational waves — ripples in space-time — from a galaxy about 130 million light years away.

Within days, astronomers had pointed every major telescope including Chandra at this galaxy.

At first, Chandra did not detect any X-rays from this gravitational wave source, but a week later it did.

This is the first time light of any kind – including X-rays -- has been seen from a gravitational wave event.

Chandra's observations help reveal this was a merger between two neutron stars that produced a jet pointing away from us.

This is a historic discovery that ushers in a new era of astrophysics and allows scientists to explore the Universe like never before.

 

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