Incredible New Footage Captures Two Stars Colliding Like We’ve Never Seen Before

The aftermath of an epic collision involving at least one neutron star has been captured for the first time in the millimeter range of radio frequency wavelengths.

The result is a recording of a short-lived gamma-ray burst – one of the most energetic ever observed and one of the brightest lingering afterglows we have ever seen. The data can help scientists learn more about these extreme events and their effects on the space around them.

And there’s an incredible timelapse of the event, the light of which appears to have traveled some 6 to 9 billion light-years across the Universe, to be picked up by the Atacama Large Millimeter/Submillimeter Array (ALMA) in November 2021.

“This short gamma-ray burst was the first time we’ve attempted to observe such an event with ALMA,” said physicist Wen-fai Fong of Northwestern University.

“Afterglows for short bursts are very hard to find, so it was spectacular to see this event shine so brightly. motivates to observe many more of these with ALMA, and other telescope arrays, in the future.”

Gamma radiation bursts are the most powerful explosions known in the Universe. In just 10 seconds, a gamma-ray burst can emit more energy than a star like the Sun emits in 10 billion years.

And they are important; as we saw in the first neutron star collision ever observed, it is in explosions like these that elements heavier than iron are forged and ejected into the Universe. The gold ring on your finger is the product of an extreme stellar calamity.

We know that neutron star collisions produce a type of gamma-ray burst known as a short-lived gamma-ray burst, or SGRB. These last only a few milliseconds and leave behind a brilliant afterglow as the ejected from the explosion slams and interacts with the gas of the interstellar medium.

Typically, these SGRBs are not seen in radio wavelengths, which can make them a bit difficult to interpret.

“These explosions occur in distant galaxies, which means that the light they emit may be quite faint for our telescopes on Earth,” explained astrophysicist Tanmoy Laskar from Radboud University in the Netherlands.

“Before ALMA, millimeter telescopes were not sensitive enough to detect these afterglows.”

Timelapse of the event recorded by ALMA. (T. Laskar, S. Dagnello, ALMA [ESO/NAOJ/NRAO])

Because this particular event, named GRB 211106A, was so far away, it was not detectable by our current gravitational wave astronomy instruments. Energetic X-rays accompanying the brief explosion were picked up by NASA’s Neil Gehrels Swift Observatory.

However, galaxies as distant as GRB 211106A’s host are not detectable in X-ray wavelengths – and dust in the region meant Hubble’s optical observations were no better at locating the source.

Because of this, scientists working only with the X-ray burst believed the location of the explosion to be relatively close. So they turned to ALMA, the first time millimeter wavelengths had been used to try to observe and contextualize a gamma-ray burst event.

“Hubble observations revealed an unchanging field of galaxies,” Laskar said.

“ALMA’s unrivaled sensitivity allowed us to more accurately pinpoint the location of the GRB in this field, and it turned out to be in another faint galaxy, which is further away.

“That, in turn, means that this short-lived gamma-ray burst is even more powerful than we first thought, making it one of the brightest and most energetic on record.”

When neutron stars collide, the result is spectacular: an explosion accompanied by jets of matter that burst outward at a significant percentage of the speed of light. If we are lucky, these jets are oriented such that one is more or less directed towards us, so we see the eruption as a gamma-ray burst.

Millimetre-wavelength observations allowed the researchers to measure some key properties of GRB 211106A; namely, the aperture angle of the jet, which can be used to infer SGRB rates in the Universe, and a more accurate measure of GRB energy.

“Millimeter wavelengths can tell us about the density of the environment around the GRB,” said astronomer Genevieve Schroeder of Northwestern University.

“And, when combined with X-rays, they can tell us about the true energy of the explosion. Because emission at millimeter wavelengths can be detected longer than in X-rays, the The millimeter emission can also be used to determine the width of the GRB jet.”

The researchers found that GRB 211106A has unusual properties, both in its host galaxy and in its energy profile.

This ultimately suggests that there is greater diversity in the properties of SGRBs than is currently accounted for, meaning that continued observation and classification of these events is warranted.

So while this is the first millimeter foray into these incredible explosions, it is extremely unlikely to be the last.

“ALMA breaks the playing field in terms of capabilities at millimeter wavelengths and allowed us to see the faint and dynamic Universe in this kind of light for the first time,” Fong said.

“After a decade of observing short GRBs, it is truly amazing to see the power of using these new technologies to unwrap surprise gifts from the Universe.”

The search was accepted in Letters from the Astrophysical Journaland is available on arXiv.

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