NASA researchers have used supercomputers to simulate the collision of two neutron stars, offering fresh insight into these cosmic events. The incredibly detailed simulation, which was conducted at NASA’s Goddard Space Flight Center, provides a visual representation of the moments before, during, and after the cataclysmic collision. The simulation was created to better understand and predict the gravitational waves and electromagnetic radiation that are produced when neutron stars collide.
Neutron stars are the remains of massive stars that have gone supernova. They are incredibly dense, with a teaspoonful weighing about a billion tons. When two neutron stars orbit each other, they eventually spiral inwards due to the emission of gravitational waves, culminating in a violent collision. These events are rare, but they are of significant interest to scientists as they are thought to be responsible for the creation of heavy elements like gold and platinum.
The new simulation not only provides a visual representation of the collision but also models the physics involved in the process. This includes the generation of gravitational waves, the creation of heavy elements through a process known as ‘r-process nucleosynthesis,’ and the emission of electromagnetic radiation across a wide spectrum. The simulation utilises equations from general relativity and a detailed microphysical model of the neutron star matter.
One of the key findings from the simulation is that the resulting gravitational waves have a unique signature that should be detectable by current and future gravitational wave observatories. This provides a new method for astronomers to identify and study these events. The simulation also showed that a significant amount of heavy elements is ejected during the collision, which could explain the abundance of these elements in the universe.
The simulation is based on a real event that was observed in 2017, known as GW170817. This event was the first time a neutron star collision had been observed in both gravitational waves and electromagnetic radiation. The researchers used data from GW170817 to calibrate their simulation, ensuring it accurately represented real-world events.
The simulation was run on a supercomputer known as ‘Discover,’ which is housed at NASA’s Center for Climate Simulation. It took over a month to complete, using 2,000 processors running in parallel. The final result is a detailed, three-dimensional representation of a neutron star collision, providing an unprecedented level of detail and accuracy.
Overall, the new simulation provides a valuable tool for scientists studying neutron star collisions. It not only offers a visual representation of these events but also provides a wealth of data that can be used to test and refine theories about these cataclysmic events. As our understanding of these events and the physics involved continues to grow, simulations like this will only become more important. They will help shape our understanding of the universe and the fundamental processes that have shaped it.