How to Build a Star
Scientists create a piece of a star in their labs to better understand how actual stars work
The Z machine rendered above uses blasts of electricity to briefly re-create the surface of white dwarfs. (Courtesy Leah Flippen / Don Winget / The University of Texas)
Astronomers use instruments on Earth to study moons, planets, stars, and other objects in outer space located light-years away. But one group of researchers is examining stars right here on Earth—by creating a piece of a white dwarf (burning stars near the end of their life) in the lab.
Astronomer Don Winget of the University of Texas at Austin and his team use the world’s largest X-ray generating machine to create a hot gas similar to the surface of white dwarfs.
White dwarfs no longer undergo the powerful reactions that fueled them as younger stars. But they do emit leftover heat and light until they cool down. These stars have scorching outer layers of plasma, a special state of matter similar to gas.
Astronomers typically use telescopes to study the exteriors of white dwarfs. But a couple of years ago, Winget thought of creating plasma similar to that of a white dwarf for a closer study.
Using a machine that generates the most powerful electrical pulses that can be created by humans, Winget and his team heat up hydrogen gas. For a fraction of a second, a 20,000-degree-Fahrenheit gas-like substance is created, much like the plasma found on the surface of white dwarfs.
“Astronomy has now become an experimental science,” Winget told Discover magazine.
So far, the researchers have been able to create starlike plasma about 30 times. Scientists can use the data from these experiments to learn more about white dwarfs. For example, by measuring the amount of light emitted by the lab plasma, they can infer how much energy the plasma loses as time passes. This allows them to estimate the age of white dwarfs.