Behind the Scenes at the Princeton Plasma Physics Lab - Atlas Obscura
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Princeton, New Jersey

Behind the Scenes at the Princeton Plasma Physics Lab

Learn about PPPL's research about nuclear fusion— the process that powers the sun— and how we can use it as a source of energy on this special access laboratory tour!

Join us on Obscura Day for a special visit to the Princeton Plasma Physics Laboratory (PPPL)!

PPPL is a national collaborative laboratory of the U.S. Department of Energy managed by Princeton University. Researchers at the lab study plasma physics and nuclear fusion, and are working to develop fusion energy as a clean, safe, and affordable source of power. The history of the lab began in 1951 with Princeton professor Lyman Spitzer, Jr., who was not only the founder of PPPL but also inspired the development of the Hubble Space Telescope. The story goes that Spitzer, who was an avid skier, came up with the idea for a figure-eight shaped “stellarator” on a ski trip to Aspen, Colorado. He launched his project a few months later in a former rabbit hutch a few miles from Princeton University.

The lab's flagship machine is the recently upgraded National Spherical Torus Experiment (NSTX-U). Inside this machine, scientists take hydrogen nuclei and heat them to temperatures hotter than the center of the sun while keeping them in place via electromagnets that are 100,000 times stronger than the earth’s magnetic field at the surface. The experiment attracts researchers from all over the world and is a crucial step in the quest to develop fusion energy – the same energy that powers the sun and the stars.

During this event, attendees will get a behind-the-scenes look at the NSTX-U control room and other experiments at PPPL. The afternoon will also include talks by physicists and engineers, videos, and demonstrations and activities.

Take a New Jersey Transit Northeast corridor train to Princeton Junction or to Princeton. A schedule is available here. You can either take a cab or other transportation from Princeton Junction. Information on taxi services is available here.


  • Two tours at 10:00am - 12:30pm & 1:00pm - 3:30pm. Make sure to double-check your reservation time!
  • Ticket Cost: Free, but capacity is limited. RSVP REQUIRED.
  • Adult visitors MUST bring a valid photo ID (passport or license) for entry. All visitors are welcome, but non-citizens are required to provide their citizenship, date of birth, and place of birth in advance. 


Email Larissa at

Advance Tickets Only. No Refunds or Exchanges.

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