Since the beginning of civilization, humans have marveled at the night sky and pondered the vast stretches of the universe. The invention of telescopes in the 17th century revealed the first details of the Moon and the planets in our solar system. Four hundred years later, space-based observatories such as NASA’s Hubble and Kepler regularly capture amazing vistas of billions of galaxies millions of light years away.
Despite these advances, astronomers have only been able to infer the meaning of the images they capture. Now scientists have a laboratory on Earth to better interpret astronomical observations, refine the latest models of how stars and planets are born and die, and strengthen their understanding of the workings of the cosmos. Their new laboratory is the National Ignition Facility.
The “laboratory” is NIF’s 10-meter-diameter target chamber, where 192 laser beams converge on different targets to produce temperatures, pressures, and densities that are similar to those in the cores of stars, supernovae, and giant planets. These experiments are particularly relevant to astrophysics, the branch of astronomy focused on understanding the physics of the universe.
The mechanisms that drive stars and other astrophysical phenomena such as supernovae, black holes, and even planetary interiors are not well understood. By creating tiny parcels of plasmas (gases containing ions and electrons) under extreme conditions, scientists can better understand the physical processes that, until now, we’ve been able to observe only from afar.
In effect, NIF allows researchers to “visit” parts of the universe they can never access, either because the objects exist millions of light years away or their environments are far too hostile to physically explore. In this way, NIF experimenters are transforming astronomy from an observational to an experimental science.
“From microjoules to megajoules and kilobars to gigabars: Probing matter at extreme states of deformation,” Physics of Plasmas 22, 090501 (2015), September 17, 2015.