An artist’s impression of a possible ninth planet. It would be quite large — at least as big as Earth — with a thick atmosphere around a rocky core. CreditCalifornia Institute of Techonology
July 15th was a historic occasion as it marked the first time we were able to see close-up pictures of Pluto’s surface. Traveling at over 30,000 mph, New Horizons snapped some very interesting pictures of the dwarf planet’s surface as it came within 47 thousand miles of it, beaming back to us details never before seen. What New Horizons captured for us was a first glimpse at mountain ranges and deposits of methane & nitrogen ice.
Since Pluto’s discovery by Clyde Tombough in 1930, it has remained a great mystery. It’s difficult to study since it’s about 3 billion miles away from the sun. The Hubble Space Telescope has been able to capture images of the dwarf planet, but Hubble is really geared towards taking pictures of giant objects like galaxies, not dwarf planets–so the images we have of Pluto are fuzzy. However, Pluto is about to get its first sharp images courtesy of the New Horizons spacecraft as it passes the dwarf planet by 7,800 miles by July 14th. With this date looming only next month, let’s take some time to take a fresh look at Pluto and the seven biggest misconceptions that people have of it.
The first color image of Pluto and its moon, Charon, was taken by the Ralph color imager aboard NASA’s New Horizons spacecraft on April 9. The image is a preliminary reconstruction which will later be refined by the New Horizon science team.
NASA released photos on Wednesday that show details that astronomers have only dreamed of: first images captured of Pluto’s moons by New Horizons probe in 2015.
This week the International Astronomical Union (made famous in the eyes of the public for reclassifying Pluto as a Dwarf Planet) gave Pluto’s newly discovered moons their official names. Previously known as “P4” and “P5”, these tiny moons are now named Kerberos and Styx respectively. The names were the result of an online naming contest where people could suggest and vote on their favorite names. You may have seen news a few months ago that one of the moons was named Vulcan (after the Roman god of fire, but also the native world of Dr. Spock from Star Trek). Vulcan won the naming contest, but in the end the official decision was up to the IAU. Here at the planetarium we were a little bummed about the decision to cast out the vote for Vulcan as a name..
Anyways…
The IAU wanted to keep with the Pluto/Underworld theme and Vulcan just didn’t fit in with that! Pluto was the Roman god of the Underworld and it’s largest moon was named Charon, after the ferryman who transported souls across the river Styx. In 2005 two more moons were discovered. They were named Nix and Hydra. Nix (originally spelled Nyx) was the mother of Charon, and Hydra was a many-headed serpent that guarded the underworld. Kerberos (spelled this way to distinguish it from the asteroid already named Cerberus) was the three headed dog that guarded the mythical entrance to the underworld. Styx of course is the mythical river that souls must cross in order to enter into the underworld.
The new moons are very small (Styx is barely visible in this Hubble image). These moons aren’t much bigger than downtown Baton Rouge!
Irene W. Pennington Planetarium 