We've been learning about exoplanets, or planets located outside our solar system, at a fast clip in recent years. NASA has confirmed over 5,000 exoplanets, but the planets orbiting star HR 8799 are pretty special. A new time-lapse video shows their celestial dance over the course of 12 years.
HR 8799's planets are history-makers. In 2008, HR 8799 was the first system to have multiple planets directly imaged. Since then, Northwestern University astrophysicist Jason Wang has been using the W.M. Keck Observatory in Hawaii to monitor the exoplanets. That's where the images for the time-lapse come from. In just a few seconds, you can witness over a decade of motion of the HR 8799 planets.
You'll notice the central star is covered up. That's to help us see the faint planets around it. The video has been processed to bring the planets into focus and to smooth out their motion.
"It's usually difficult to see planets in orbit," said Wang in a Northwestern statement Monday. "Astronomical events either happen too quickly or too slowly to capture in a movie. But this video shows planets moving on a human time scale. I hope it enables people to enjoy something wondrous."
HR 8799 is just over 133 light-years away from us in the constellation Pegasus. That still puts it in our cosmic neighborhood. It's a much younger star than our sun and its planets are massive gas giants bigger than Jupiter. What we're seeing is only a small part of their journey. The planet closest to the star takes 45 years to go around. The one farthest away takes almost 500 years.
The video is an exercise in beauty. It's about a sense of wonder. Said Wang, "There's nothing to be gained scientifically from watching the orbiting systems in a time-lapse video, but it helps others appreciate what we're studying."