Every time NASA launches a mission, I'm filled with excitement -- there's so much out there and so much to learn.
However, most of these missions require a LOT of patience. Most of the things we want to study are way out there -- millions and even billions of miles away.
In the case of the New Horizons spacecraft, it's been a loooong wait. The spacecraft lifted off from Cape Canaveral aboard an Atlas V rocket on Jan. 19, 2006. That's right: we've been waiting nine years for a moment that will occur next Tuesday!
New Horizons begins its journey to Pluto on Jan 19, 2006 (Image Credit: NASA/Ken Thornsley)
New Horizons has been traveling through space for more than nine years on its way to Pluto.
Discovered in 1930, Pluto was long considered our solar system's ninth planet. But after the discovery of similar intriguing worlds deeper in the distant Kuiper Belt, icy Pluto was reclassified as a dwarf planet. This new class of worlds may offer some of the best evidence about the origins of our solar system.
Here are some cool facts from NASA about Pluto and this mission:
1. If the Sun were as tall as a typical front door, Earth would be the size of a nickel and dwarf planet Pluto would be about the size of the head of a pin.
2. Pluto orbits our sun, a star, at an average distance of 3.7 billion miles.
3. One day on Pluto takes about 153 hours. That's the time it takes for Pluto to rotate or spin once. Pluto makes a complete orbit around the sun (a year in Plutonian time) in about 248 Earth years.
4. It is thought that Pluto has a rocky core surrounded by a mantle of water ice with other ices coating its surface.
5. Pluto has five known moons. Pluto is sometimes called a double-planet system due to the fact that its moon Charon is quite large and orbits close to its parent planet.
6. There are no known rings around Pluto.
7. Pluto has a thin, tenuous atmosphere that expands when it comes closer to the sun and collapses as it moves farther away -- similar to a comet.
8. NASA's New Horizons spacecraft is the first mission sent to encounter the Pluto-system and other members of the Kuiper Belt.
9. Scientists do not think Pluto can support life as we know it. Although, some scientists believe it is possible Pluto could possess a hidden ocean under its surface.
Pluto and its moon, Charon, are a fascinating pair: Two icy worlds, spinning around their common center of gravity like a pair of figure skaters clasping hands. Scientists believe they were shaped by a cosmic collision billions of years ago, and yet, in many ways, they seem more like strangers than siblings.
A high-contrast array of bright and dark features covers Pluto's surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon's surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice.
New Horizons' latest photo of Pluto and Charon taken on July 8, 2015 (Credits: NASA-JHUAPL-SWRI)
"These two objects have been together for billions of years, in the same orbit, but they are totally different," said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.
Charon is about 750 miles across -- about half the diameter of Pluto -- making it the solar system's largest moon relative to its planet. Its smaller size and lower surface contrast have made it harder for New Horizons to capture its surface features from afar, but the latest, closer images of Charon's surface show intriguing fine details.
Newly revealed are brighter areas on Charon that members of the mission's Geology, Geophysics and Imaging team (GGI) suspect might be impact craters. If so, the scientists would put them to good use.
"If we see impact craters on Charon, it will help us see what's hidden beneath the surface," said GGI leader Jeff Moore of NASA's Ames Research Center. "Large craters can excavate material from several miles down and reveal the composition of the interior."
In short, said GGI deputy team leader John Spencer of SwRI, "Charon is now emerging as its own world. Its personality is beginning to really reveal itself."
New Horizons' closest approach to Pluto will be at 7:50 a.m. July 14, which is next Tuesday. Its cameras and instruments will be hard at work studying this dwarf planet close-up for the first time in our history. I can't wait! So what happens after it flies by Pluto at 30,800 mph?
As part of an extended mission, the spacecraft is expected to head farther into the Kuiper Belt to examine one or two of the ancient, icy mini-worlds in that vast region, at least a billion miles beyond Neptune's orbit.
It is believed that these Kuiper Belt objects become comet nuclei and get nudged out of the Kuiper Belt and head into our solar system by the gravitational pull of a large celestial object flying by.