Spotting Planets Around Other Stars

Clockwork Worlds: Recording Planets and their Orbits from a Distance

Wow, this is really cool. Watch this little video a few times…it’s a time-lapse sequence of planets orbiting a star about 129 light-years away from us in the direction of the constellation Pegasus. The time-lapse was made over a period of years starting in 2009. These planets — which are Jupiter-size and larger — lie quite far from their star; their orbits range from 40-year periods for the closest one to 400 years for the most distant one. You can read more about their discovery and the work astronomers have done to chart their orbits at NASA Astrobiology

Not so long ago, worlds like these were lost in the glare of their stars, and it fell to astronomers to devise ways to block out the starlight so they could even have a chance of spotting distant planets. Now, using such instruments as the Gemini Planet Imager, they can do that.

I find it remarkable that we can “see” these planets. Finding alien worlds is more than just a science-fiction adventure. It’s key to understanding many things about our own solar system and about the environment of our galaxy. Sure they look like dots of light, but they’re worlds. Maybe not just like our own, but they’re still distant worlds, and gives us yet more proof that our galaxy is a veritable treasure trove of exoplanets. It now appears that the galaxy is rich with them, as the Kepler mission showed us so dramatically when it surveyed just a tiny portion of the galaxy. I really think that more discoveries await. The next steps will be to study the planets we find in great detail to learn more about their atmospheres as well as their progression as they are born and evolve in their systems. All of this leads inexorably to looking for life.   That will be a huge challenge, but given how far we’ve come now in our planet searches, I’m sure that astronomers and astrobiologists will figure it out, perhaps within our lifetimes. Stay tuned!