And while you may not have felt it, LIGO sure did.

And these gravitational waves are the ripples from a collision of the most massive neutron

star pair we have ever witnessed.

As you may know, this isn't LIGO's first rodeo with gravitational waves.

They're famous for the first ever detection of gravitational waves back in 2015, which

were the result of a black hole merger.

Then LIGO detected their first ever gravitational waves from a neutron star merger in 2017.

And this latest neutron star collision, observed in 2019, was given the catchy name...GW190425.

Just as a quick refresher, LIGO is the Laser Interferometer Gravitational-Wave Observatory.

It detects these tiny disturbances in the fabric of space-time, like ripples on the

surface of a pond.

They travel through the universe at the speed of light, and typically only distort physical

space here on Earth by about the width of an atom's nucleus.

And even though gravitational waves are practically infinitesimal by the time they reach us here

on Earth, the strongest ones we can measure with our instruments are caused by gigantic

cosmic events: like collisions of black holes or neutron stars.

The 2019 event was actually detected on only one of the two U.S. LIGO sites—the one in Louisiana—

because the detector in Washington was offline.

This is LIGO's first single-detector event, which is impressive, but it also means researchers

weren't able to narrow down the merger's location as much as they might have been able

to with two detectors online.

Though as of right now, the merged neutron stars could exist anywhere in an area that makes

up about 20% of the sky, not exactly a small window.

The team deduced from the data that the combined mass of the two neutron stars was about 3.4

times greater than the mass of our Sun, making it the most massive neutron star merger we've

ever observed.

And it's different from the 2017 event, too, because it wasn't accompanied by any

kind of electromagnetic radiation that we could detect—it was missing what some scientists

call a 'flash of light'.

And perhaps most intriguingly, it appears to have created an object with “unusually

high mass”.

Higher mass than we've ever seen before from a neutron star merger, and higher than

we expected.

With this second observation of neutron stars colliding, scientists are gathering clues

about how these cosmic events affect our universe.

A neutron star is a super-dense remnant of a star after it erupts into a supernova.

They're basically laboratories of really extreme physics.

They tell us a lot about space and how it evolves over time, so to witness and measure

a collision of two of them can yield some really rich insights.

Like LIGO's observation of this in 2017 was the first ever, yes, so very exciting

But it also yielded data confirming the hypothesis that neutron stars crashing into each other

are a source of heavy elements, producing stuff like gold and platinum.

They're basically heavy element factories.

And we still don't know a lot about what happens to neutron stars after they merge

together—so scientists were hoping this latest detection would drop some hints.

All of the data from this 2019 event—the massive object left behind in the merger's

wake, plus the lack of electromagnetic radiation—leads some scientists to believe that these two

neutron stars may have become a black hole after they merged.

Maybe.

But it could also just be that we weren't looking in the right place at the right time

and we missed the flash of light.

So astrophysicists are going to keep probing this data to see if they can gain any more

insights, and hopefully LIGO will capture many more events like this in the future to

tell us even more about the crazy cosmic collisions that both create and disturb the very fabric

of our universe.

In order to do this, LIGO does has some serious upgrades planned, so check out this video here

to learn all about that.

And make sure you subscribe to Seeker for all things space-time.

If you have another cosmic event you want to see us cover, let us know down in the comments

below and as always, thanks so much for watching.

I'll see you next time.