4th Anniversary of Our First Visit to Pluto

July 14, 2019

(Artist Interpretation of New Horizons Probe Pluto FlyBy - Credit NASA/JHU APL/SwRI/Steve Gribben)

On January 19, 2006, the interplanetary space probe New Horizons was launched on the Atlas V rocket under NASA's New Frontiers program. Fun Fact: It was the fastest man-made object ever launched from Earth, at approximately 10 miles/16 kilometers per second. The team collab between John Hopkins University Applied Physics Laboratory (APL) and the Southwest Research Institute (SwRi) was led by S. Alan Stern, and the primary mission was to perform the first ever flyby of the pint-sized Pluto system. It was on this day in 2015 that the persevering probe finally reached its destination.

(New Horizons Image of Pluto and Charon - Image Credit NASA)

There were some adventures along the way for the little probe though, such as a brief encounter with asteroid 132524 APL before making its closest approach to the planet Jupiter a little over a year after blast off. This brush with jumbo Jupiter's gravity gave the spacecraft some necessary vroom-vroom, and also put the probe's new scientific gear to good use as it returned the most up-to-date data about the planet's atmosphere, moons and magnetosphere to Earth. The remainder of the trip was a hibernation situation for the probe to keep the on-board systems fully charged.

(Jupiter and it's moon Io from New Horizons - Image Credit NASA)

It was at the end of 2014 that New Horizons was awakened to prepare for the full Pluto experience; and almost nine years to the day after its January 2006 launch, the "little probe who could" began its approach phase for a closer look. Six months later, on July 14, 2015 (at 11:49 UTC if you're wondering), it flew a mere 7,800 miles/12,500 kilometers above Pluto and became the first spacecraft to get cozy with the dwarf planet. The probe did its tech thang like a champ until the last recorded data was received on October 25, 2016.

Just for kicks, here's our (retired) senator from Maryland, Barbara Mikulski, the day before the flyby waiting excitedly and anxiously! Isn't it rad to have representatives who care about this stuff? We think so! (Vote, people.)

Democratic Maryland Senator Barbara Mikulski at New Horizons Pluto Fly By - Image Credit NASA

During the mission, New Horizons also gained important info about the Kupier belt, a ring of bodies just beyond Neptune, where little P resides. (Here's a little animation of an ancient object moving through space that New Horizons picked up!) Pluto was the first of said objects discovered orbiting within the belt, and this discovery was made in 1930 by a fella named Clyde Tombaugh. It is the largest known plutoid, or ice dwarf, but it is only about one-sixth the mass of our Moon and one-third its volume in comparison. Speaking of moons, Pluto has five that are known: Charon (the largest), Styx, Nix, Kerberos and Hydra.

Fun Fact: In Greek mythology, Pluto is considered the ruler of the underworld. In earlier legend, he is referred to as Hades (before it became the more common name for the underworld itself). Charon is said to be the ferryman of Hades who carried the souls of the newly deceased across the rivers Styx and Acheron, which divided the world of the living from that of the dead.

Pluto was classified as the ninth planet in our solar system when New Horizons was launched, but was later reclassified as a dwarf planet by the International Astronomical Union (IAU). A dwarf planet is a celestial body resembling a small planet but lacking certain technical criteria that are required to tag it as a "real" planet. Aww, poor guy. But we still love wee Pluto, of course, and consider it an intricate part of space and jewelry! Check out this badass Pluto and Charon collection of accessories, and give the gift of Pluto love to someone special in your life.