Pluto Mission Takes Aim at Last Unvisited Planet

National Geographic ^ | 2.15.05

[GeronL]

2015??

Yeesh, and how about a daily thread on this?? =o)

[Marano NYC]

The last part of the article sums up the controversy . Pluto is not considered a planet by some scientists. Yet it should still be studied. There is also the breakaway Neptune moon theory.

[ambrose]

2015.... to send a bloody probe...

Ray Bradbury's Martian Chronicles had us colonizing Mars by 1999!

I hope we're not hitting some technological spell akin to the 1400s to 1800s where basically very little happened...

[ambrose]

My

Very

Earnest

Mother

Just

Served

Us

Nine

Pizza pies!

[GeronL]

Nope. Its a transformative period. We are awaiting the next big breakthrough, and it might be private ships going to Mars.

[WestVirginiaRebel]

Yeah, nothing happened except for Leonardo Da Vinci, Copernicus, Galileo, Newton, Ben Franklin...

[ambrose]

They were brilliant theorists. What we didn't see until the 1800s, however, was life transforming technological advances (railroad/telegraph...)

[Dallas59]

[ambrose]

Now why did you have to go and do that? Now I really want to go to Pluto.

[Ruth A.]

Thank you. Just yesterday my 10 year old asked me if I thought Pluto was a planet. We tried to determine the criteria of a planet and why it might not be considered a planet. The discussion moved to asteroid belts, too. The poll in our family was unanimous that Pluto was a planet.

[Nexus6]

Pluto's estimated surface temperature is a brutally cold, at -378 to -396 degrees F

not so bad, just be sure to pack a sweater.

[ambrose]

My vote is an errant moon of Neptune..

[Ruth A.]

Noted. Of course, I did say that since I grew up with it being a planet that I would have to be hard pressed to classify Pluto otherwise. Apparently the body of astronomers feels likewise.

[WestVirginiaRebel]

I read somewhere that one of Jupiter's moons (Ganymede?) is large enough to qualify as a planet.

[Captain Beyond]

bump

[FreedomCalls]

Pluto is not considered a planet by some scientists.

Yeah, of the terrestrial planets, it is the smallest. There are even seven moons larger that it is. Check this chart out:

[FreedomCalls]

I read somewhere that one of Jupiter's moons (Ganymede?) is large enough to qualify as a planet.

See my #17. Ganymede (at Jupiter) and Titan (at Saturn) are both larger than Mercury.

[FreedomCalls]

The poll in our family was unanimous that Pluto was a planet.

Based on what?

[Ruth A.]

There is no firm definition of a planet, but the International Astronomical Union has ruled that Pluto meets the criteria. Generally, Pluto is considered a planet because it orbits the sun and is large enough that its own gravity gives it a circular shape.

This same reasoning, but not stated as elegantly.