Arcs of electricity crawl over the Z Machine at Sandia National Laboratories in Albuquerque like an energetic spiderweb. Astronomers and physicists from McDonald Observatory and Sandia are using the machine, which was designed to study nuclear weapons, to simulate the atmospheres of white dwarf stars. The machine collects electricity from a standard power grid, compresses it, then stores it. It discharges that power in a burst that lasts less than 100 billionths of a second. The discharge zaps gases like those found in white dwarfs, briefly reproducing conditions on the surfaces of these hot, "dead" stars. [Sandia National Laboratories]
With a bang and a flash of light, a star is born. It’ll live for only a tiny fraction of a second. Yet in that flicker of time it will help astronomers understand the final stage of life of most stars. And that will help them better understand all of time, from the age of the universe to its fate.
The “star” lives inside the Z machine at Sandia National Laboratories. The machine uses powerful bursts of electricity to create X-rays. They zap gases and other materials, telling scientists how matter behaves under extreme conditions.
For this experiment, the machine zaps a tube of hydrogen gas. It’s heated to thousands of degrees to replicate conditions at the surface of a white dwarf star. That creates a state of matter known as a plasma. Don Winget is a University of Texas astronomer who works on the project.
WINGET: It is the most powerful X-ray source on the planet Earth. We’re using it to heat up our plasma and create the conditions that are not similar to the conditions in a white dwarf plasma, but are the conditions in a white dwarf plasma.
A white dwarf is the final stage of life for a star like the Sun — a dense, hot ball that slowly cools and fades. These “dead” stars help reveal the history of the universe.
WINGET: We’ve found so many things that we can learn about physics from the white dwarf stars. We can map out the age and history of our own galaxy in some detail. We can constrain the age of the universe.
For the white dwarfs to provide those details, astronomers must know two things about them — how hot they are and how heavy they are. And that’s where the “Z” experiments have helped. More about that tomorrow.
Script by Damond Benningfield, Copyright 2013
For more skywatching tips, astronomy news, and much more, read StarDate magazine.