There are hundreds of billions of galaxies — some experts even estimate trillions — so finding 5,000 planets within all those may not seem like much.
Eric Mamajek would disagree. A deputy program scientist with NASA's exoplanet exploration program, he says it wasn't that long ago that we weren't even aware of these celestial bodies.
"Just 30 years ago, we didn't know of any exoplanets," Mamajek explains. "We didn't even know if there were planets outside of the solar system orbiting other stars."
Mamajek believes it's now possible that within the next generation we may be able to find signs of life on exoplanets orbiting other stars.
Studying exoplanets gives us the opportunity to learn about worlds that are unlike anything we have here in our solar system. One of Eric's favorites, though he says it has not been 100% confirmed, is known as J1407b. He calls it the "white whale" that NASA has been following for years.
"It looks like a huge system of rings, but about 200 times larger than Saturn's rings," Mamajek recalls. "And, it hasn't passed in front of its star again... So, this planet is either on a really wide orbit or maybe it was unbound to the star to begin with. It may be just freely floating from space, we don't know."
- Eric Mamajek, deputy program scientist with NASA's exoplanet exploration program
