In 1992, astronomers discovered the first known planet outside our solar system. Now, more than 30 years later, NASA has announced a new milestone: Researchers have officially identified more than 6,000 exoplanets. Scientists think that some exoplanets, like those that orbit the sun in the TRAPPIST-1 solar system, could support life.
“We wondered for hundreds of years if there were planets around other stars,” says Emily Rice, an astronomy professor at Macaulay Honors College in New York City. “And now we know that the answer is a resounding yes.”