From the earliest days of the space race, the Energy Department and its National Labs have been indelibly linked with humanity’s quest to journey to the stars. This week on Energy.gov, follow along as we chart that course, from space power systems to dark energy and beyond. These are just a few of the stories we’ll be sharing as we explore science on the cosmic frontier:

• Since the launch of the Transit 4A navigation satellite in 1961, our nation’s reach in space has been furthered by nuclear energy. Learn about the space power systems that have made discoveries about the sun, planets and interstellar space possible.
• As the space race nears its 60th anniversary, tens of thousands of pieces of space junk have accumulated around Earth’s orbit. Learn about space traffic and how Livermore Lab scientists are working on a system that could help prevent collisions in space.
• Fusion is the power of Sun and all the stars and could represent a safe and reliable source of energy here on Earth. At the Energy Department’s Princeton Plasma Physics Lab, scientists are creating a star on Earth in the National Spherical Torus Experiment, an innovative magnetic fusion device.
• As the Curiosity rover explores Gale Crater on Mars, it stops periodically to check out its surroundings and take samples for analysis. It’s primary scientific goal? To determine whether Mars was once habitable. To accomplish this, it uses a variety of scientific instruments, one of which is the ChemCam, an instrument developed by the Energy Department’s Los Alamos National Lab to rapidly analyze rocks and soil to determine their composition.
• Not limited to science and energy as we know them, we’ll look to the future with features on space-based solar power and the science behind science fiction.
• On Friday, join us for a Twitter #LabChat on dark energy — the theoretical force that is causing the universe to expand at an accelerating rate — at 12 p.m. ET. We’ll be joined by Fermilab scientist Brian Nord, a member of the Dark Energy Survey collaboration and host of the website DarkEnergyDetectives.org, and Berkeley Lab scientist Eric Linder, an expert on dark energy and the accelerating universe. Between now and Friday, submit your questions to @energy using #labchat, leave a comment on Facebook.com/energygov, or send an e-mail to newmedia@hq.doe.gov.

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