Gravitational waves have been a major focus of astrophysics for the last few years. According to the general theory of relativity, these events create ripples in time and space as an object accelerates. This occurs many light-years away from us. However, those ripples can be detected on Earth. Nevertheless, the gravitational wave concept in astronomy and astrophysics is only in its early days, and it requires more researching and observing. A newly published paper, however, suggests that a new type of gravitational wave could be spotted in the near future.
To this day, scientists have only noticed gravitational waves that came from colliding black holes and stars. However, new research indicates that scientists will be capable of spotting a whole new type of gravitational wave within the next decade. It is expected that they will use a new tool called a pulsar timing array (PTA.) The waves could spring from pairs of black holes which are 1 million times the mass of our Sun. In such pairs, one black hole orbits the other.
Previous gravitational wave events you might have heard about were spotted by LIGO and Virgo, which are long, underground tunnels where laser light is being split and then brought back together. A gravitational wave is made when one of the split laser beams starts to wobble and interferes with another laser beam that has split, which makes the shape of the wave visible in a detector, though the detectors can only discover wobbles that occur at least 10 times per second. Less frequent wobbles could be created by things such as galaxies that are merging with massive black holes at their center.
Scientists believe that a different kind of experiment would contribute to the discovery of these certain black holes, and they believe that experiment could be pulsar timing arrays. The experiment measures the timing of pulsars, which are the light sources that send beams to earth at regular intervals. The procedure for conducting the experiment was explained in detail by Chiara Mingarelli, an astrophysicist from the Flatiron Institute, in a blog post for Scientific American.
“PTAs take advantage of the regular arrival times of radio pulses from millisecond pulsars to search for gravitational waves. When two supermassive black holes coalesce into one, the mergers bathe the universe in low-frequency waves, stretching and squashing the fabric of spacetime. The pulsars and the Earth behave like buoys on the surface of a choppy spacetime sea, bobbing up and down as the waves pass by. This causes changes in the timing of pulsar pulses that can be detected in carefully designed experiments here on Earth.”
Mingarelli’s model, which was published in Nature Astronomy, used real data to discover how many galaxies would radiate this kind of wave. The discovery of the new type of gravitational wave will depend on several things such as ambient noise isolation.
Scientists gave this experiment a ten-year prediction, so we will have to wait and see whether they succeed or not.