Seven years ago today NASA launched the New Horizons spacecraft to Pluto. It’s halfway to a scheduled fly-by in July 2015. NASA’s website says:
After 10 years and more than 3 billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds we’ve only just discovered on the outskirts of the solar system.
Pluto gets closer by the day, and New Horizons continues into rare territory, as just the fifth probe to traverse interplanetary space so far from the Sun. And the first to travel so far, to reach a new planet for exploration.
Did you catch that – “new planet.” Not a dwarf planet. (Much less a “lump of Kuiper belt junk”.)
All of you who spent December repeatedly watching Miracle on 34th Street realize here is a golden opportunity to get justice for this persecuted member of the solar fraternity –
“Your honor, the National Aeronautic and Space Administration, an official agency of the United States government, recognizes Pluto as a planet…”
[Via Michael A. Burstein.]
The sentiment to retain Pluto as a planet is understandable. Why, what will we do with our copies of “Nine Planets” by Alan Nourse if Pluto is only a Dwarf Planet, Trans-Neptunian Object, Kuiper Belt Object, or (worse) a “Plutino?”
Thinking ahead, though, demoting Pluto may be the only sensible course. So far, we’ve discovered some 8 or 9 other bodies like it, three of which are about the same size and the others about half Pluto’s diameter. There is no reason to expect the list to end there. In fact, I’ve seen speculation that as our reach into the outer limits of the solar system extends, we may discover dozens, possibly even hundreds of substantial bodies. If we allow Pluto today, we will never know how many planets there will be in the Sol System tomorrow.
Pluto will remain a planet in the hearts of its admirers forever.
A planet … and a cartoon dog.
Long after the Human Race is gone, Pluto will continue to be a planet, immortalized as such on the gold plaques on Pioneers 10 and 11.
…and when aliens discover the Pioneer probes adrift in space, millions of years from now, they’ll say to themselves, “I wonder why those Earthlings were so fond of a cartoon dog?” (Sound of rim-shot followed by pistol shot.)