For thousands of years, people have looked up at the stars, recorded observations, and noticed patterns. Some of the first objects early astronomers identified were planets, which the Greeks called “planētai,” or “wanderers,” for their seemingly irregular movement through the night sky. Centuries of study helped people understand that the Earth and other planets in our solar system orbit the sun—a star like many others.

Today, with the help of technologies like telescope optics, space flight, digital cameras, and computers, it’s possible for us to extend our understanding beyond our own sun and detect planets around other stars. Studying these planets—called exoplanets—helps us explore some of our deepest human inquiries about the universe. What else is out there? Are there other planets and solar systems like our own?



Though technology has aided the hunt, finding exoplanets isn’t easy. Compared to their host stars, exoplanets are cold, small and dark—about as tricky to spot as a firefly flying next to a searchlight … from thousands of miles away. But with the help of machine learning, we’ve recently made some progress.



One of the main ways astrophysicists search for exoplanets is by analyzing large amounts of data from NASA’s Kepler mission with both automated software and manual analysis. Kepler observed about 200,000 stars for four years, taking a picture every 30 minutes, creating about 14 billion data points. Those 14 billion data points translate to about 2 quadrillion possible planet orbits! It’s a huge amount of information for even the most powerful computers to analyze, creating a laborious, time-intensive process. To make this process faster and more effective, we turned to machine learning.

