Monday, July 6, 2015

Pluto (the Planet, not Mickey's Dog)

With the New Horizons probe reaching Pluto in just a few more days, it seems like a good time to address a couple of questions:

1.  Is Pluto a planet?

I say YES! My opinion has no basis in science -- it arises strictly from a combination of irrational prejudice and childhood nostalgia. And I think if we're going to kick Pluto out of the society of planets, there a few other pieces of debris that should also be expelled, namely Mercury, Venus, Earth, and Mars. After all, the Solar System basically consists of four enormous planets -- Jupiter, Saturn, Uranus, and Neptune -- and a bunch of rocks. My colleague David Weintraub informs me that I won't get very far with a definition of "planet" that excludes the Earth, but I think we should be more open-minded.

2.  What's the best science fiction story about Pluto?

My favorite is "Wait it Out" by Larry Niven.  An astronaut is marooned on Pluto and freezes solid. But instead of dying, he finds his nervous system turned into a superconductor, leaving him conscious enough to wait for rescue. This is not only the Pluto story I remember most vividly, it's the only story about Pluto that I can recall clearly. Any other favorites out there?

9 comments:

Unknown said...

On the other hand, no pluto makes Holst's The Planets complete.

robk said...

short story of Clifford.D.Simack "Construction Shack" is about expedition to Pluto :)that only 3-4 page with fun twist :)

Priya Palande said...

I am a fan of your blog! Including Earth as a piece of debris takes the cake for me...

Anonymous said...

"Have spacesuit - will travel" ended up on Pluto didn't it?

Robert Scherrer said...

That's right -- I had forgotten about Have Spacesuit will Travel. Part of the action takes place on Pluto. It's a great book to introduce kids to science fiction -- mine loved it.

Kathy said...

"World of Ptaavs," an early novel of Niven's, has a climactic scene set in Pluto, if memory serves.

Anonymous said...

My favorite: Kim Stanley Robinson's Icehenge. The first manned expedition to Pluto discovers something unexpected....

The Lensmen series had a race of beings that lived on Pluto - they weren't native to it though.

Unknown said...

Hi,
I have a Plutonian physics question. :) For these types of long planetary missions where a fairly precise flyby is planned, is it sufficient to use Newtonian mechanics to plan the trajectory of the satellite, or does NASA use the general theory to correct?

Thanks!

Robert Scherrer said...

I don't know the answer off-hand, but my guess is that Newtonian gravity is sufficient. Recall that the effects of general relativity become largest as you get closer to the sun (e.g., precession of Mercury).