How to best learn about the edge of the solar system? Actually go there. NASA says its Voyager 1 spacecraft—which launched in 1977—has entered an area of the solar system that scientists didn't know about, the AP reports. "We do believe this may be the very last layer between us and interstellar space," says chief scientist Ed Stone. NASA is calling the region a "magnetic highway" where particles from inside the sun's magnetic sphere "zoom out, and higher-energy particles from outside to stream in."
Scientists based their conclusion on Voyager's instruments, which show a 1,000-fold decrease in low-energy particles from our solar system and a five-fold jump in high-energy particles from interstellar space, reports Huffington Post. Now Voyager 1 may stay in this in-between zone for two or three years, NASA says. Then comes its future in interstellar space, reports Scientific American: powering down around 2025 and passing a neighboring star in about 40,000 years. After that, it will be billions of years before it approaches another star. (Read more Voyager 1 stories.)