Pluto's Moon Gives Up Secrets

This Week In Science writes "When Pluto's moon, Charon, occulted a distant star on July 11, 2005 two groups of astronomers were there to witness the fleeting moment. Based on what they saw, the scientists were able to determine that Charon has very little atmosphere, has a radius of 605 km, and is about 1.7 times denser than water. The density calculation implies that Pluto and Charon were once two separate proto-planets that because of a chance encounter are now bound by gravity."

Comments

New Horizons

[hound3000]

Too bad it will be another ten years before New Horizons gets there to really start telling what Pluto / Charon is all about.

Re:New Horizons

[Anonymous Coward]

Dont worry there are two groups of astronomers already there.

Wait a second

[Lars T.]

From the article:

The team also found that the density of any atmosphere on the moon must be less than a millionth of that of the Earth. This argues against the theory that Pluto and Charon were formed by the cooling and condensing of the gas and dust known as the solar nebula. Instead, Charon was likely created in a celestial collision between an object and a proto-Pluto.

"Our observations show that there is no substantial atmosphere on Charon, which is consistent with an impact formation scenario," Gulbis said. Similar theories exist about the formation of the Earth-moon system.

That's not the same as "the density calculation implies that Pluto and Charon were once two separate proto-planets that because of a chance encounter are now bound by gravity".

astronomers on Pluto?

[Mr Abstracto]

"... two groups of astronomers were there to witness the fleeting moment..." How long have we been sending astronomers to pluto?

double double toil and trouble

[Bootle]

Does that really say "occulted"? What the eff? Do they mean "occluded"? Seriously, are the editors all 14 years old?

Re:double double toil and trouble

[Bootle]

Well, I was wrong to point the finger so hastily!

Occultation

Might still be the stupidest word I've encountered in a LONG time!

Re:double double toil and trouble

[gstoddart]

Occultation

Might still be the stupidest word I've encountered in a LONG time!

Well, it's a word of latin origins which has been well established in the the language ....

From Webster ...

Main Entry: 1occult
Pronunciation: &-'k&lt, ä-
Function: transitive verb
Etymology: Latin occultare, frequentative of occulere
: to shut off from view or exposure : COVER, ECLIPSE
- occulter noun

Turned into a noun, we get

One entry found for occultation.
Main Entry: occultation
Pronunciation: "ä-(")k&l-'tA-sh&n
Function: noun
1 : the state of being hidden from view or lost to notice
2 : the interruption of the light from a celestial body or of the signals from a spacecraft by the intervention of a celestial body; especially : an eclipse of a star or planet by the moon

Since when did Slashdot become a forum for whining people to express their dissatisfaction with words outside of their vocabulary? It's been in use for a few hundred years, it's too late for you to vote.

Re:double double toil and trouble

[Bootle]

It's stupid because there already is a word for that meaning, occlude. All this can do is create confusion and obfuscate communication (perhaps the point).

I get to vote due to the fact that language is plastic, evolving, and not perfect. A horse gets me to where I'm going just fine, why should I bother inventing car? There's always room for improvement, including simplification. Words *do* fall into disuse.

If it makes you feel any better, I feel that onus is also a stupid word because of its redundancy.

Re:double double toil and trouble

[gstoddart]

It's stupid because there already is a word for that meaning, occlude. All this can do is create confusion and obfuscate communication (perhaps the point).

Actually, being a scientific term, it adds specificity.

They could have used the word eclipse too. But it gets used in specific contexts (usually wrt the sun or the moon and Earth). Both occultations and Eclipses are forms of Syzygy -- a really odd word indeed. Block, hide, cover, obscure are all words which more or less mean the same thing -- except occultation refers to the event which is causing the obscuration of another celestial body. (And for the record, it's conjugated in the same manner as indentation, so it's hardly a novel word construct.)

It's not intended to be a layman's term -- it's the technical term used by that group of scientists. Kinda like how doctors haven't dumbed down their vocabulary to simply say "the patient is sick" -- there's a need to describe specific, differentiated things, and they use different words for that.

If it makes you feel any better, I feel that onus is also a stupid word because of its redundancy.

*shrug* Onus literally means "burden of proof". Onus is the most succinct of the words you could choose to convey that.

It's a language full of words with similar meanings. Until we've got the whole Newspeak thing worked out and we only have a few words to express everything, we'll just have to cope. Scientific and technical areas will always have their historical peculiarities out of necessity.

Wordsd do fall into disuse, this one, however, is still widely used.

Re:double double toil and trouble

[Anonymous Coward]

Completely off topic with little hope of return...

It shouldn't be a surprise that there is more than one word meaning the same thing... The English language has one of the widest vocabularies because it largely a combination of (at least) 3 others - Anglo-Saxon (Germanic), French and Latin, and many others have contributed over time. This is due to the many contributors by historical pillage/plunder/invasion etc and more recently due to the plasticity of usage. Hence there are often 3 words with similar meanings, eg: the "learned" version derived from the Latin that the clergy and educated people used, one derived from the French, and the "coarsest" usage is usually the Anglo-Saxon derived version - I've been looking for a good example, but the best I can do right now is "royal" (F) and "regal" (L) - same meanings different language sources... any better examples out there?

Re:double double toil and trouble

[thegarbageman]

So let's start burning thesauruses, shall we?