Gravitational waves and what they mean for space exploration
Gravitational waves is the first direct spotting of space phenomenon predicted by relativity theory.
Scientists recently announced they had discovered gravitational waves, an invisible wave or ripple in space and time created by extreme gravitational forces. They had long ago been predicted to exist by Albert Einstein. We haven’t been able to detect these waves before because they are only produced during large-scale destructive space events such as the merger of two black holes, or the collision of two neutron stars.
The discovery of this phenomenon will allow us to “see” things in the universe we couldn’t see before, either because they were hidden or invisible. The waves can be tracked to provide an accurate example of these other space elements that aren’t visually detectable.
What does this mean? The discovery of gravitational waves will usher in a new era of astrophysics.
Physicist Brian Greene explained it best during an interview with Mashable: “We can observe the universe in this new way, not using light, but using gravity.”
How Did Scientists Discover Gravitational Waves?
The ripples observed by scientists were created during the collision of two massive black holes. In comparison, they were about thirty times larger than the sun. These ripples were a major component of Einstein’s general theory of relativity, predicted back in 1915.
When these two forces collided, they generated fifty times more energy than that of all the stars in the observable universe. We’re talking ridiculous amounts of energy here, so much that it’s difficult to fathom.
Scientists observed the event using special equipment located in Washington and Louisiana. The Laser Interferometer Gravitational-Wave Observatory (LIGO) instruments allowed them to witness the black holes merging.
Because everything visible in the observable universe is technically from the past — light takes a long time to travel to us — the black hole collision is said to have happened nearly 1.3 billion years ago. So it’s safe to say our discovery of gravitational waves has been billions of years in the making.
It’s funny because black holes are said to hold the key to understanding the history of our universe.
“Black holes are kind of like the dinosaur bones of the universe, so in some sense, we can do something like stellar archaeology and look at the history of the universe through the products of these large stars,” says Matthew Evans, a scientist at LIGO.
What Does This Mean for Space Exploration?
Before the finding, scientists were only able to rely on infrared, visible light and ultraviolet to observe the universe as seen through optical and radio telescopes. Now, they can actually use gravity to detect a lot of invisible elements. Basically, gravitational waves allow them to look at the outline of something in space. More importantly, they can observe and record how these waves alter space and time.
Experienced astrophysicist Katie Mack says,
“Everything that happens in the universe — a bit of light traveling from one place to another, or mass moving around — that’s happening in space-time, and it’s affecting space-time and it’s being affected by space-time.”
Hopefully now you can see why this discovery is so important. Scientists will be able to study not just the invisible space objects themselves, many of which have already been theorized by physicists, but also their relationship to other elements of space.
New Technology to Fuel Exploration
The European Space Agency (ESA) launched a test, the LISA Pathfinder mission, to conduct research for future technology plans. Its goal is to understand how a space-based gravitational wave detection system would work.
If the test mission is successful, the plan is to send a full-scale version of LISA into space, which will be used to measure and detect waves. As you’d expect, the space version will carry a similar name: eLISA.
If scientists equip the eLISA with internal air compressors, it will allow them to generate vibrationless movement of satellite components, which ultimately have little to no affect on their findings. In other words, movement of the satellite won’t skew their perceptions and negatively impact their observations.
Boeing Satellite Systems used technology like this in their satellites, and it works flawlessly. Let’s hope the engineers from the European Space Agency follow suit.
Either way, the end result is we will soon know more about the universe we live in. Perhaps the most exciting part of this news is we will have a greater understanding of the things we can’t “see” with our own eyes.