Huiyan satellite helps measure new type of gravitational wave
“The collision spews out material from the surfaces of the objects, which can not happen if one or both of them do not have a surface – and black holes don’t have a surface, they have an event horizon”, says Edo Berger at Harvard University.
“It’s so attractive. It’s so lovely it makes me want to cry”.
Their collision also provided the loudest, closest and most precisely located gravitational wave signal yet received by humans. “He was able to create a theory that was so dramatically new that 100 years later we’re still trying to prove some of it’s most dramatic predictions”. The others were the results of two black holes merging.
The satellite-based Fermi gamma ray telescope, it turned out, had seen something: a brief blast of high-energy photons, apparently emanating from the cloudy, elliptical galaxy NGC 4993.
The radiation this emits looks nothing like an ordinary supernova or exploding star.
A neutron star merger should trigger a very strong gamma-ray burst, with most of the energy released in a fairly narrow beam called a jet. They concluded that those two neutron stars were destined to crash into each other in about 300 million years.
The existence of gravitational waves, which have been described as ripples in space-time, was first confirmed in 2015, and the discovery led to this year’s Nobel Prize in Physics being awarded to three key contributors to the LIGO-VIRGO collaboration.
That morning, all of a sudden, scientists’ cellphones began to ring.
“We can now fill in a few more tiles in the jigsaw puzzle that is the story of our universe”, said Laura Cadonati, deputy spokeswoman for the LIGO Scientific Collaboration and professor in the school of physics at Georgia Tech. He had been in a mundane organizational meeting, which was immediately abandoned.
“It’s not like anything we’ve ever observed before”, Drout said. Just two seconds later, both NASA’s Fermi Gamma-ray Space Telescope and the ESA’s International Gamma Ray Astrophysics Laboratory detected a short gamma-ray burst in a similar region of the sky.
For McEnery, the discovery ushers in a new age of cooperation between gravitational-wave experiments and experiments like her own.
When Virgo and LIGO detected the signal of the gravitational waves in August, an alert was sent out to observatories across the world. But that helped pinpoint its location to an area small enough to search with optical telescopes. Astronomer Benjamin Shappee was there – and he was asleep.
“I think we are converging towards a time when LIGO/Virgo alerts will become public and will be distributed within minutes”, Howell says.
“These last couple of years, first of all with the detection of black holes mergers and now a neutron star merger, I really feel we are opening up a new field, and that’s what I wanted to do and now we’ve done it”. A year ago marked the first time we’ve been able to observe the phenomena, and so far, all the gravitational waves we’ve observed have been caused by particularly intense events, such as the merging of neutron stars.
The Carnegie team worked quickly to make observations, because they only had about an hour until this spot was no longer visible in the sky. “It was just completely unexpected, out of the blue”, Shappee says. The UCSC group is supported in part by the National Science Foundation, Gordon and Betty Moore Foundation, Heising-Simons Foundation, and Kavli Foundation; fellowships for Foley and Ramirez-Ruiz from the David and Lucile Packard Foundation and for Foley from the Alfred P. Sloan Foundation; a Niels Bohr Professorship for Ramirez-Ruiz from the Danish National Research Foundation; and the UC Institute for Mexico and the United States (UC MEXUS). “We have entered a new era of multi-messenger astronomy!” “It was an incredibly amazing moment, because it just stood out there”. “We didn’t expect to see this so soon”, says Eric Howell of the University of Western Australia, who studies neutron stars, gravitational waves and gamma ray bursts. We have to look elsewhere for the origins of the remaining 89 elements that naturally occur on Earth.
It was also direct confirmation that short bursts of gamma-ray radiation are linked to colliding neutron stars.
“So that’s now confirmation that gamma ray bursts are made by colliding neutron stars”.
“That debris is odd stuff”.
“It’s not related to the Big Bang as such, but it is a little bang if you want, a bang that is crucial for making rare elements”, Dr Wolf said. It’s hard to put definite numbers on their size, because factors like their rotational speeds can influence the dynamics of the inspiral, which in turn affects the shape of the waveform-and it’s by comparing this waveform to predictions from general relativity that we determine their masses. Further study has revealed that the merger likely produced a mind-blowing “10 Earth masses of gold and uranium”, according to Columbia University associate professor Brian Metzger. “It’s a ridiculously huge amount on human scales”, Kasen says. Nope, our sun is too small for the kinds of energy needed to produce heavier elements. Matt Nicholl, an astronomer at the Harvard-Smithsonian Center for Astrophysics, submitted a proposal on behalf of the team to take ultraviolet measurements with Hubble – possibly the shortest proposal ever written.
Powerful telescopes at the European Southern Observatory’s and other sites in Chile, as well as instruments in the USA, were trained on the area to see if they could detect new light.
This is an idea first postulated by Einstein in his General Theory of Relativity which, among other things, suggests that space and time are not separate and that events experienced at one point in time by one observer can be experienced at a different point in time by a different observer.
Prof Stephen Hawking of Cambridge University told BBC News that this was “the first rung of a ladder” for a new method of measuring distances in the Universe.