We may have detected a new source of gravitational waves (maybe)

Over the weekend, astronomer J. Craig Wheeler of the University of Texas at Austin launched speculation over a potential new LIGO detection by tweeting: “New LIGO. Source with optical counterpart. Blow your sox off!”

By optical counterpart, he probably means that astronomers could observe light emitted by the gravitational wave source. This suggests the source is neutron stars as, unlike black holes, they can be seen in visible wavelengths. LIGO researchers have long-anticipated this possibility, setting up partnerships with optical observatories to rapidly follow-up on potential signals prior to formally announcing a discovery.

LIGO spokesperson David Shoemaker dodged confirming or denying the rumours, saying only “A very exciting O2 Observing run is drawing to a close August 25. We look forward to posting a top-level update at that time.”

Speculation is focused on NGC 4993, a galaxy about 130 million light years away in the Hydra constellation. Within it, a pair of neutron stars are entwined in a deadly dance.

Newscientist.com, Aug. 23, 2017 - Exclusive: We may have detected a new kind of gravitational wave.

- and -

Starting August 17 and continuing every night since, the Visible and Infrared Survey Telescope for Astronomy at Cerro Paranal in Chile has taken survey images intended to spot a kilonova, the proposed observational signature of two colliding neutron stars, based on a LIGO gravitational wave detection. Another instrument on the same mountain took spectra from a part of that region of the sky for over four and a half hours from August 19 to 22.

Quantamagazine.org, Aug. 25, 2017 - For Astronomers, a Neutron Star Merger Could Eclipse the Eclipse.

There was even some controversy when NASA removed a publicly available photo from their website!

The story goes, LIGO, which is coming to the end of it's second run (labeled, O2), today, Aug. 25, spotted something but this time it was not black holes. Well, the only collisions that would be strong enough to create gravity waves would another massive object. Neutron stars fit the bill as would a neutron star-black hole merger (the kilonova term). The guy did the tweet. On Monay, The Great American Eclipse happened. While that was happening, optical telescopes including Hubble Space Telescope, turned their attention to NGC 4493.

The Quanta article is a good read about why this is stirring up astronomers. So much, a few ignored the eclipse altogether to focus on viewing something nobody has ever seen. There are multiple stories at various sites all speculating about what has been found.

Since neutron stars are not black holes you can see what is happening. That is important as visible light and x-rays can be measured to check what theories predict. There has been speculation that nuclear fusion found in stars can only get you part of the way up the periodic table of elements before the star would collapse. They are now suggesting that "r-process" (this is the name given to the production of heavy elements like gold and uranium) may actually be cause by neutron star collisions and maybe even black hole collisions. Since you cannot see a black hole collision then it becomes very fortuitous to stumble across a neutron collision!

This is happening right now! Real science. In the heavens above. This may change our understanding of several puzzling questions of our universe.

Have we detected a new kind of gravitational wave?

I guess we have to keep watching the skies!!

More on the r-process

Current theories suggest they most likely emerged during what researchers call an r-process—as in rapid. As part of the process, large numbers of neutrons would come under high densities, resulting in capture by atomic nuclei—clearly, an extreme environment. The most likely candidate for creating such an environment is a supernova, but there seem to be too few of them to account for the amounts of heavy elements that exist. In this new effort, the researchers offer a new idea. They believe it is possible that PBHs [primordial black holes] occasionally collide with neutron stars, and when that happens, the PBH becomes stuck in the center of the star. Once there, it begins pulling in material from the star's center.

... if a PBH happened to bump into a neutron star, it would take up residence in its center and commence pulling in neutrons and other material. That would cause the star to spin rapidly, which in turn would fling material from its outermost layer into space. The hurled material, the researchers suggest, would be subjected to an environment that would meet the requirements for an r-process, leading to the creation of heavy metals.

phys.org, Aug. 24, 2017 - New theory suggests heavy elements created when primordial black holes eat neutron stars from within.

That is from yesterday! The r-process can also happen if neutron stars collide. The idea presented in the article is from this month.

This is really cutting edge. I can see why astronomers are excited!

But it is not just them. The amount of energy involved offers clues to sub-atomic world of quantum mechanics. The numbers have to add up. Quantum mechanics has been around for nearly a hundred years and having an astronomical observation confirm sub-atomic physics is a crazy idea that I like!

Time to call Bob Lazar with his "Gravity A" and "Gravity B" waves!

a reply to: Blue Shift

I had my phone stolen. I can't call him.



For those that don't know...

ATS: When Bob Lazar Declared Gravity As a Wave.

So in less than two or three years we (or better, science) managed to pick up not only one type of gravity wave but two different ones?
Is that correct?

originally posted by: verschickter
So in less than two or three years we (or better, science) managed to pick up not only one type of gravity wave but two different ones?
Is that correct?

It's just a regular gravity wave, but with a free gamma ray burst at the same time. With two black holes merging, they just get the gravity wave. With two neutron stars glowing brightly at 600,000K at the surface, along with intense magnetic and gravitational fields (gravity = 2 x 10^11 that of Earth, magnetic field = 10^8 to 10^15 times that of Earth), we can only imagine what is going on when the two cores only 10km merge together to form a single black hole. Then the astronomers can figure out the exact sequence of events. Within a few seconds, enough matter the equivalent of one star is converted into pure energy and sent across the universe at the speed of light. Enough energy to actually cause the space-time fabric itself to stretch by a fraction of a nanometer.

a reply to: stormcell

Wow, I could even follow your explanation! Where did you get the number 10km from? Do you mean the unit of length as in kilometers?

a reply to: verschickter

I did not make the title!

A better one would have been, We may have detected a new source of gravitational waves.

That does a better job of explaining what happened. The same instrument, LIGO, detected a gravity wave and there were not from black holes which means visible to our other instruments.

I think I will update the title of this post thred! Thanks for the confusion!

a reply to: stormcell

Thanks for the explanation!

Nice post! It is d@mn near poetry! I like the ending, "pure energy".

originally posted by: verschickter
a reply to: stormcell

Wow, I could even follow your explanation! Where did you get the number 10km from? Do you mean the unit of length as in kilometers?

From wikipedia

en.wikipedia.org...

a reply to: TEOTWAWKIAIFF

My first question was genuine as I´m a total beginner when it comes to the greater mechanics of the universe, the confusion was also genuine

You´ll find me rambling about AI, programming, robotics, automatisation and hazzard detection systems, that´s what I did for a living. Here, I´m the "noob"

I also agree with you on stormcells "poetry"! While reading it, It was like a small movie in my head (Kopfkino, google it).

originally posted by: stormcell
From wikipedia

en.wikipedia.org...

You... you...you´re good!

a reply to: verschickter

I find the whole topic interesting: cosmology. How this *waves hands above head* comes about. There are many questions.

I'm interested, a fan, kind of amazed by what we have done so far, then being wowed but what is just around the corner with new instruments.

I wrote a thread about a star being ripped apart by a supermassive black hole. I started learning by explaining what all the data meant. I get excited about this stuff even if I don't know what is going on.

Having a bunch of people who do work in the field all eager over a tweet and sensor logs... well, makes me wonder what is happening!

a reply to: TEOTWAWKIAIFF

Having a bunch of people who do work in the field all eager over a tweet and sensor logs... well, makes me wonder what is happening!

That´s what I liked and miss from my job (retired). A room full of people sitting together to solve a problem, being all disolved in the work exchanging thoughts and ideas. Professional but also like family. It has it´s own magic. And when the breakthrough is achieved, it´s like a cloudy sky parted by warming waves of knowledge. Sometimes, during my small coffee breaks, I´d stand in a corner of the room, sipping at my coffee and watching the flow until I dove back in. Like gears that grip perfectly into each other!

Like little neurons firing, to make up a huge superbrain that can achieve small wonders.



and then you get back from weekend, all the ID cards don´t work anymore for that level, your personal workdrive is empty and and you know exactly you(as in the team) were too close to something already in existance but darker than vantablack or it goes dark because smarter people than you found out what you were playing with.

And you know what you and the team figured out works so you take on the next project with even more enthusiasm. But I drift off, sorry! I just miss it.

Update

“New LIGO. Source with optical counterpart. Blow your sox off!” [Tweet that started the furor]

[Craig] Wheeler later apologized on Twitter. “Right or wrong, I should not have sent that tweet. LIGO deserves to announce when they deem appropriate. Mea culpa,” he wrote.

Public records show that NASA’s Fermi Gamma-ray Space Telescope has spotted γ-rays emerging from the same region of sky as the potential gravitational-wave source.

On 22 August, a Twitter feed called Space Telescope Live, which provides live updates of what the Hubble Space Telescope is looking at, suggested that a team of astronomers was looking at a binary neutron-star merger using the probe’s on-board spectrograph, which is what astronomers would normally use to look at the afterglow of a short GRB [gamma ray burst]. The Hubble tweet has since been deleted. Public records also confirm that multiple teams have used the Hubble Space Telescope over the last week to examine NGC 4993, and state as their reason that they are trying to follow up on a candidate observation of gravitational waves.

On 23 August, a commenter on the blog of astrophysicist Peter Coles, of Cardiff University in the UK, noted that NASA’s Chandra X-ray observatory had jumped into the action, too.

Update 25 August: The LIGO–Virgo collaboration posted its top-level update, saying: “Some promising gravitational-wave candidates have been identified in data from both LIGO and Virgo during our preliminary analysis, and we have shared what we currently know with astronomical observing partners. We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share.”

Nature.com, Aug. 25, 2017 - Rumours swell over new kind of gravitational-wave sighting.

Fermi, LIGO, Virgo, Hubble, and Chandra, were all pointed at NGC 4993 at one point last week! They are going to do due diligence on the collected data (which they should). The article does a decent timeline of events. They also coyly hint that they knew about the merger happening a bit before the tweet was sent out.

It seems like this will be a major announcement when all the data is scrubbed. Even if they only caught the merger of two neutron stars that would be huge. But to get all the observations on it by multiple teams both visual and gravitational... wow!

I'm always on MIT news so will keep an eye out for the release!

In August 2017, astronomers reported that a gamma-ray burst, named GRB 170817A, and a possible gravitational wave, tentatively named GW170818, that may have been emitted in the collision of two neutron stars,

Wikipedia - NGC 4993.

Even Wikipedia updated their page! It is also sourced from the New Scientist article. He may apologized about the tweet but the news had to come out somehow.

Well, the news confirmed that two neutron stars had merged. And the observations continued as earth came out from behind the sun. Now, the write ups done, the sigmas reached, and submitted article published they have a good idea what happened after the merger.

The scenario that emerged is that the initial merger of the two superdense neutron stars caused an explosion that propelled a spherical shell of debris outward. The neutron stars collapsed into a black hole whose powerful gravity began pulling material toward it. That material formed a rapidly-spinning disk that generated a pair of jets moving outward from its poles.

As the event unfolded, the question became whether the jets would break out of the shell of debris from the original explosion. Data from observations indicated that a jet had interacted with the debris, forming a broad "cocoon" of material expanding outward. Such a cocoon would expand more slowly than a jet.

"Our interpretation is that the cocoon dominated the radio emission until about 60 days after the merger, and at later times the emission was jet dominated," said Ore Gottlieb, of the Tel Aviv University, a leading theorist on the study.

"We were lucky to be able to observe this event, because if the jet had been pointed much farther away from Earth, the radio emission would have been too faint for us to detect," said Gregg Hallinan of Caltech.

The detection of a fast-moving jet in GW170817 greatly strengthens the connection between neutron star mergers and short-duration gamma-ray bursts, the scientists said. They added that the jets need to be pointed relatively closely toward the Earth for the gamma ray burst to be detected.

We measured an apparent motion that is four times faster than light. That illusion, called superluminal motion, results when the jet is pointed nearly toward Earth and the material in the jet is moving close to the speed of light.

-Kunal Mooley, National Radio Astronomy Observatory (NRAO) and Caltech.

phys.org, Sept. 5, 2018 - Radio observations confirm superfast jet of material from neutron star merger.

The fact that this was detected was considered a miracle. That the earth happened to pointing towards one of the poles so we detect them in the first place is even more of a miracle!

And if that were not enough there is this story also at phys.org from the day before saying that they *should* be able to put a filter in-line with more powerful lasers that will dampen the physical interaction between photons and the mirrors to increase the sensitivity of gravity wave detection and increase the volume of space being measured by 8-fold!

Boosting gravitational wave detectors with quantum tricks.

If they can do this around the time JWST comes on-line then then it would take astronomy to a whole new level!