Although the world of science was mainly focused on the run-up to the Great American Eclipse last week, a group of astronomers was working on something with far more game-changing implications in the long term — the possibility that a neutron star collision could also produce gravitational waves, much like black holes could.
As noted by Wired, the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) had made a groundbreaking discovery in February of 2016 when it announced that it had spotted gravitational waves emerging from a collision of two black holes. This was followed up in June 2016, when the LIGO team had sighted a second instance of two black holes colliding and producing the waves. And in January of this year, LIGO’s second observing run had yielded a third wave-producing black hole merger.
According to Science News, recent LIGO alerts might have yielded something even more fascinating than the three gravitational wave discoveries mentioned above. The potential discoveries were made around the galaxy codenamed NGC 4993, which is found about 134 million light-years away in the constellation of Hydra, and since mid-August, there have been at least three observations made by the Hubble Space Telescope, with one on Tuesday hinting at the possibility of the “first electromagnetic counterparts to gravitational wave sources.”
Three days prior to the aforementioned Hubble sighting, the Chandra X-ray Observatory zeroed in on that same section around NGC 4993. Around the same time, the Gemini Observatory’s Chile telescope also made reference to an “exceptional LIGO/Virgo event,” among many other similar observations around the same area in question.
In an announcement posted on Friday morning, the LIGO team noted that there has yet to be a neutron star collision confirmed to be capable of producing gravitational waves.
“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.”
Similarly, Enrico Ramirez-Ruiz of the University of California, Santa Cruz played it coy when he told Wired that any such detection could make for “one of the greatest discoveries” ever in the field of astronomy. As the publication noted, he declined to provide any specifics on the results of the LIGO team’s analysis.
On the other hand, there have been other scientists, such as Princeton University astrophysicist David Radice, who are more confident that LIGO did find something noteworthy in recent days. While he told Science News that it’s “very, very likely” that the sightings are legitimate, he added that he isn’t sure whether neutron star collisions were the source of the gravitational waves. Radice, as noted by Science News, is not affiliated with LIGO.
Astronomers have long been hoping for a sign that neutron star smashups also produce gravitational waves in the same way that black holes do. According to Science News, these smashups are said to take place where the universe’s heaviest elements are created, and the confirmation of a neutron star collision producing gravitational waves could offer some clues regarding the extremely dense material that makes up neutron stars.
So is it possible that there was a neutron star collision that produced gravitational waves? According to the National Geographic, the LIGO team is working overtime to make sure that the gravitational waves did actually manifest, and that both the waves and the gamma ray burst came from the same source. This burst was spotted on August 17 in NGC 4993 and codenamed GRB170817A, and such events usually take place when two neutron stars collide.
“We really want to have a chance to understand the data we have been collecting and ensure that we are confident in what we make public,” said David Shoemaker, LIGO spokesperson, in a statement.
“Incremental releases of information at this point could easily need retraction or modification in the weeks to come. We are working as hard and as fast as we can!”
UPDATE [8/27/2017, 8:41 p.m. ET] – Original report updated to include statement from LIGO’s Shoemaker, additional information on possible neutron star collision.
[Featured Image by posteriori/Shutterstock]