Our solar system is unique in the sense that it only has one star-the sun. If, like many other solar systems, ours had two twin stars, it is possible that they could form a black hole.

Eric Hirschmann, a BYU professor and astrophysicist, and his colleagues, David Neilsen and Matthew Andersen collaborated with individuals from Louisiana State University and Long Island University to work on simulating the collision of two dead stars, or stars that no longer give off light.

In today's issue of the scientific journal "Physical Review Letters," these researchers have demonstrated in a four-page article an important part of solving one of the questions of the universe.

"What happens when the stars collide is affected by the magnetic field," Hirschmann said.

They found that stars' magnetic fields slow down the process of colliding to form a single star. If there is a magnetic field, then an additional orbit is created in the last 12 milliseconds.

The extra orbit makes it possible for planned technology to pick up signals (gravity waves) under the right conditions.

Hirschmann said that compared to the sun, these stars are smaller. He compared them to the size of the Utah County. The stars are also around 60 km from each other and this makes their collisions predictable.

"We're interested in what happens when they [the stars] run into each other," Hirschmann said. He said one of two things could happen: they can form another bigger star, or the stars can collapse completely and create a black hole.

"The computer solves the equation and tells us what happens," Neilsen said. "It comes in a movie format."

He said that it took 256 computer processors and two months to calculate and create the simulation.

Hirschmann said BYU is pleased to have one of the fastest computers in the world, the "Mary Lou 4." The simulations are founded by the National Science Foundation in search of the cause of a type of gamma-ray burst, the brightest flashes seen in space.

The BYU study will attempt to answer the question of whether or not the dead stars' collisions are the explanation for gamma-ray bursts.

The present discovery of the possibility to detect gravity waves is only a small piece of the puzzle. The professors are hoping it to be a long-term study.

"This is an ongoing thing," Hirschmann said. "We have more questions."

He also said no students were involved in this discovery, but they do have a couple of students who want to get involved.

Copyright Brigham Young University 30 May 2008