The historic detection of gravitational waves has forever changed the way we think about the universe. Here are the top three major findings from yesterday’s discovery, and what we can expect to find moving forward.
We live in an exciting time. It’s not very often that a discovery is made about our universe that completely changes how we see our world, but we are now lucky to have witnessed the detection of one of those discoveries, and it’s even got a cool name: gravitational waves.
This detection confirmed a few pretty mind-blowing things:
1) Einstein was right.
The first major confirmation is that gravitational waves are real; the final piece of Einstein’s theory of relativity is now complete. The fabric of space-time can actually fluctuate from large cosmic events, and we can now measure these events by detecting these waves.
2) Black holes exist.
Believe it or not, scientists could not actually confirm the existence of these monstrous matter-destroyers, making this yet another win for physicists and theorists. Until now, scientists could only see the effects that black holes had on other objects in the universe, but this is the first detection directly made from the black holes themselves.
3) And they exist in pairs!
Binary black holes are two black holes that orbit around each other. This detection confirmed what scientists had theorized about when a binary star system dies and can go on to create two super-massive black holes.
This shows a simulation the gravitational waves produced from the merger of two black holes. Credit: GIPHY
So, what are these gravitational waves all about?
In 1916, Albert Einstein predicted the existence of these waves as a part of his theory of general relativity. Similar to how when we put our hand in a still pool of water and then pull it through, small waves or ripples will be created and follow behind it, Einstein argued that the same kind of “waves” would be produced by the force of a massive object moving in space. However, scientists needed something big to confirm this theory, and I mean really big.
Last September, scientists at the Laser Interferometer Gravitational wave Observatory, or LIGO experiment, noticed a weird little fluctuation across their computer screen. A few seconds later, there it was again. A gravitational wave! It was the first detection of a wrinkle in the fabric of our universe. This was a discovery 100 years in the making.
Where did the wave come from?
1.3 billion years ago, long before the dinosaurs walked the Earth and well before humankind was even a blip on the radar of our solar system, two black holes whirled around each other in space. They spun around faster and faster, until they finally collided with each other and became one. The collision took only a few milliseconds and yet released 50 times as much energy as all the power of every star in the observable universe combined! This massively powerful event sent ripples of waves outward from the new black hole. Those waves have been travelling out for the last 1.3 billion years, until last September when they came slowly crashing into Earth and popped up on the screen at LIGO. The waves from the collision actually made time speed up, slow down, and then speed up again. Gravitational waves can actually change time!
Scientists estimate that one black hole was 36 times more massive than our sun, and the other was around 29 times more massive; this created a singular black hole that had about 62 times the total mass of our sun. So where did the other three masses run off to? They were sent hurling out in the form of gravitational waves. The spreading of any type of wave dissipates over time, the way a boat driving past the shore creates a large wake but the ripples that reach the shore get smaller and smaller over time. This concept is what makes finding these waves extremely difficult. While a collision of two black holes is one of the most extreme cosmic events to ever take place in our universe, the waves have been traveling for over a billion miles; making them almost unnoticeable by the time they reach Earth.
So, what happens now?
Scientists expect that merging neutron stars, and massive supernovae explosions can also produce these waves. Now that they have been detected, scientists can now listen for other events that might have fainter signatures. Being able to “see” the effects of their influence on space-time will provide a brand new tool for astronomers and other scientists, not unlike the way we currently search for gamma rays, infrared signatures and visual light, gravitational wave signatures can help us see the universe in a whole new way.
Let the science commence! The official detection of gravitational waves has now ushered in a new and exciting era for astronomy and science. We now have a brand new way of studying the universe around us and what events are taking place. This discovery could ultimately bring us closer to a true theory of everything, as we learn more about what’s happening out there, billions of miles away. Scientists can now use this tool to observe the universe. I, for one can’t wait to see what we find out next!
Check out this demonstration by NOW.SPACE editor, Heather D’Angelo, where she explains gravitational waves using stuff found around her house.
Read NOW.SPACE writer, Amy Thompson’s, take on gravitational waves here.