Observing the interior of a star is pretty much impossible at the moment. So scientists are looking at a phenomenon happening on the surface of stars to better understand their internal structure: STARQUAKES.
Similar to earthquakes here on our planet, starquakes are tremors or waves that occur on neutron stars and other massive bodies. Most stars are balls of plasma, but neutron stars are super dense so they have a crust. Neutron stars crusts are Ten billion times stronger than steel. With this Huge dense body and crust, their magnetic field are interconnected. So when a star rotates quickly, the crust is under pressure from gravity and that fast rotation, causing it to bulge out. If the structure keeps twisting, it can rip the crust open and that creates a starquake.
The resulting release of energy is vast beyond our wildest imaginations. Starquakes are the reminder that space is violent and metal as hell. The biggest starquake ever detected was from a magnetar. Magnetars are a class of neutron star with the most intense magnetic field in the entire Universe.
One starquake on a magnetar released more energy in a tenth of a second than our Sun does in 150,000 years. If the explosion had been within 10 light years of us, experts say Earth could have suffered a massive extinction. Those starquakes emit frequencies that can be detected by the Kepler Space Telescope and scientists interpreted them for our ears.
The reason astronomers looked into this because of some cosmologists believed stars were just out there not really organised. Starquakes were used to prove otherwise. In a recent paper, An international team of astronomers studied starquakes from 48 Red giants in two ancient star clusters. By measuring the waves from these starquakes, they found 70% of the stars had spins that were aligned with one another. It proved asteroseismology can be a successful tool to understand the conditions of stars and discredited these theories that stars were randomly oriented.
Studying the vibrations from stars is very similar to what seismologists do to understand the core of our own planet. For example, if you want to study the earth’s interior, we can’t just drill a hole into the centre and find out what’s going on. Something goes with stars, We can’t go in and grab a piece of a star’s centre and study it. But the waves created by those quakes can be measured. By measuring the oscillations coming to and from the centre of the star, we can understand it’s physical conditions, the size of its centre and more about its origin story.
It’s pretty wild that we can use the internal hum of stars that are light years away to figure out how our Universe formed billions of years ago. More research is happily needed. So next time you look up to stars, remember you have actually got front row seats to a celestial Concert.