NASA’s Voyager 2 has hit a number of landmarks. First launched on Aug. 20, 1977, the spacecraft has fared the depths of the cosmic abyss. On Jan. 24, 1986, it came closer than humanity’s ever gotten to the distant, gaseous planet Uranus.

 

“We knew Uranus would be different because it’s tipped on its side, and we expected surprises,” said Voyager project scientist Ed Stone. “Then we got to Uranus and saw that the poles were closer to the equator. Neptune turned out to be similar. The magnetic field was not quite centered with the center of the planet.”

Voyage 2’s flyby lasted around 5.5 hrs, with the spacecraft traveling within 50,600 mi of the planet. The researchers found Uranus was the coldest planet in the solar system, due to it lacking an internal heat source. The planet’s atmosphere was comprised of 85% hydrogen and 15% helium. About 500 mi below the clouds, scientists found evidence of a boiling ocean.

During its flyby, the spacecraft discovered 10 new moons and two rings surrounding the planet. One called Miranda piqued scientists’ interest because of its unique geography. Though 300 mi in diameter, the moon boasted canyons 12 times deeper than the Grand Canyon. Scientists believe the moon may have been shattered and then reassembled. 

“The Uranus encounter was very exciting for me,” said Voyager project manager Suzanne Dodd. “It was my first planetary encounter and it was of a planet humanity had never seen up close before. Every new image showed more details of Uranus, and it had lots of surprises for the scientists. I hope another spacecraft will be sent to explore Uranus, to explore the planet in more detail, in my lifetime.”

In 1989, the spacecraft snagged humanity’s first-ever look at Neptune, and hurdled deeper into space.

Within the next several years, Voyager 2 will reach interstellar space. Voyager 1 was the first spacecraft to reach interstellar space in August 2012.