Sunday, February 8, 2015


Here Comes Pluto!
Homer Hickam

       The first time I heard about Pluto was when Mrs. Brown, my second grade teacher at the school in Coalwood, West Virginia, said it was our 9th planet. As far as I'm concerned, it still is. Everything Mrs. Brown taught me has proved to be true so I have no reason to doubt her about Pluto, either.
Homer "Sonny" Hickam about the time he heard
about an odd little world called Pluto
      Of course, Pluto is a bit different from the other eight worlds circling our sun. For one thing, it's smaller than the others and has an odd, tilted, eccentric orbit that requires 248 years for it to move around the sun. Pluto also has several moons that Mrs. Brown didn't know about. The biggest one is Charon that we think is about half the size of its host. Imagine an Earth with a moon half its size! Talk about a high tide! The other Plutonian moons, Nix, Hydra, Styx, and Kerberos, are probably just big icy rocks but we don't know for certain. That, fortunately, is about to change.
       Any time I want to the see our solar system, I don't require fancy computer graphics. All I have to do is mentally hover over the Sun and watch hot Mercury, cloudy Venus, blue marble Earth, red Mars, the jumbled asteroid belt, banded Jupiter, ringed Saturn, robin-egg blue Uranus, and blue-green Neptune rolling along on their endless orbits. I can even swoop in and see most of the solar system's moons. There's our boot-printed Luna plus Jupiter's ice-bound Europa, Saturn's Titan with its methane seas, and all the rest. The reason I can picture these planets, moons, and asteroids is because I've seen pictures of them that were taken by spacecraft swinging by for a close look.

Our Solar System (photo courtesy of Wikipedia)
     But Pluto is still a mystery. What does it and its moons look like? We won't know until a plucky little spacecraft named New Horizons soars by this summer. It should be an amazing encounter.
      Sending a robot to Pluto wasn't easy but the initial steps here on Earth were perhaps the hardest. One of the scientists who fought to send a probe to Pluto happens to be a friend of mine, Dr. Alan Stern of the Southwest Research Institute. Before Alan got involved, NASA and the United States Congress had promised to send a couple of robotic craft to visit Pluto. The first one, the Pluto Fast Flyby, was cancelled for the lack of funds. The next one, the Pluto Kuiper Express, was cancelled for the same reason. When Alan came on board, he fought hard to get Pluto back on the "great place to visit" list and he was successful. In January, 2006, an Atlas V rocket sent New Horizons hurtling into the far wayback and the adventure was on!
New Horizons spacecraft (photo courtesy of NASA)
The New Horizons spacecraft is a pretty amazing little flyer. First off, after Jupiter gave it a gravity assist, it became the fastest spacecraft ever, zipping along at around 50,000 miles per hour. It will still be going 30,000 miles per hour when it zooms past Pluto so it will have to do a lot in a hurry. New Horizons isn't very big, only about the size of a grand piano, but packed aboard it are some amazing instruments.

Photograph of Pluto and Charon
taken by New Horizons, January 2015
(photo courtesy of NASA)
    Besides cameras, New Horizons has an ultraviolet spectrometer that will tell us a lot about Pluto's geology. It also has devices designed to measure its atmosphere, a solar wind detector, and a dust counter. It also contains the ashes of the man who discovered Pluto, an interesting fellow named Clyde Tombaugh.
Clyde Tombaugh (photo courtesy of NASA)

By every measure, Clyde Tombaugh shouldn't have discovered anything. The son of a Kansas farmer, Tombaugh put off college after hail ruined the crops and he had to work the farm. But, between plantings and harvestings, Tombaugh's eyes always strayed upward, so much so he built his own telescopes and set them up around the farmhouse. Eventually, he got a menial job at the Lowell Observatory and was tasked to look for anything that might be out beyond Neptune. A tenacious fellow, Tombaugh not only found Pluto but, beyond it, the Kuiper Belt, a primordial parking lot filled with careening planets, asteroids, rocks, and comets that had been overlooked for centuries. It was only after those amazing discoveries that Tombaugh took the time to get a doctorate in astronomy. Clearly, he was a man who couldn't wait to do what he was born to do.
          New Horizons is going to reach Pluto on July 14, 2015 but, well before that, photos of the planet and its moons are going to be sent out for us to enjoy and ponder. What will Pluto and its moons look like? Although gone now to the great schoolhouse in the sky, I'm sure Mrs. Brown would be pleased to know that one of her students is going to find out!

The Coalwood School where all the planets were taught