Enlighten Me: Astronomers celebrate gravitational waves discovery
NASA scientists announced earlier this week they have detected what happens when two neutron stars collide.
In a galaxy far away, two neutron stars slammed into each other. This resulted in gravitational waves – ripples in space time. NASA Astrophysics Director Paul Hertz says Albert Einstein predicted 100 years ago that an explosion like this could cause these kinds of ripples.
“Now Einstein thought they were so small that we would never be able to detect them, but we humans are pretty creative and we have built gravitational wave observatories in Washington State and in Louisiana,” Hertz said.
Unlike what Einstein predicted, the detectors in observatories are so sensitive that they were able to sense the gravitational waves as they passed by the Earth in August.
But more than that, after the stars merged, they released a burst of gamma rays. The energy caused the atoms to bind together and form heavy elements like platinum and gold.
“Many billions of years ago, there must have been an explosion like this in our own galaxy that formed the gold atoms that are present here on the Earth that we mine to create jewelry,” Hertz said. “What we’ve done is we’ve further expanded our understanding of where we came from and how we fit into the universe.”
As soon as NASA’s news broke earlier this week, it excited many Delawareans and local astronomers. Judi Provencal, a University of Delaware professor and a resident astronomer at the Mt. Cuba Astronomical Observatory in Greenville, said she’s been waiting for the news.
“The problem is that [the ripples] are very, very tiny, so they’re very, very hard to detect,” Provencal said.
She continued, “That’s just amazing that we’ve actually seen this happen now. The gold and the silver and everything that’s heavier than iron comes from something like that. The gold atoms and platinum atoms are out there in space and when the Earth formed, they ended up on the Earth. That to me is an amazing thing to happen.”
Provencal says she’s looking forward to learning more as NASA continues to explore the phenomenon behind neutron stars.
“I would like to know how a neutron star works, so it would be interesting what they learn from this gravitational wave detector. The neutron star - the material that makes it up - is so different from what makes up normal matter,” Provencal said.
As for what mysteries still remain, Hertz said he wants to understand the process from start to finish on how a collision causes heavy elements to form, how the elements are spread out through the interstellar medium, and what role heavy elements play in the composition of our planets.
“If we understand for instance how planets form in our galaxy, then we have a better understanding of where to look to see planets – especially planets that might be habitable, like the earth.”