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62140.  Mon Mar 27, 2006 3:20 pm Reply with quote



I would now like to draw Your Worships' attention to the popular Syrian proverb: "The son of a duck is a floater". And my question is this:


What's the biggest floater under the sun?




Saturn, Roman God of Agriculture. The planet Saturn is about 760 times the size of the earth and about 95 times as heavy, but is so low in density that it would float on water.

Oddly enough, in classical mythology, an alternative name for Saturn was Stercutus, the Roman God of Dung.


The density of Saturn is about 70% that of water. Though it's the second largest planet, after Jupiter, it is the least dense of all the planets. Its mass is less than a third of Jupiter’s.

Saturn's outer layer is a vast sea of liquid hydrogen and helium perhaps as much as 30,000 km deep. There is no definite boundary between ‘atmosphere’ and ‘surface’ so Saturn cannot really be said to have an ‘atmosphere’ (or indeed ‘surface’).

The famous rings of Saturn are made of particles of dust and ice ranging from less than a millimetre across to the size of vans. They are 270,000 km in diameter but less than one kilometre thick – thin enough to see stars through them. It used to be thought there were six major concentric rings, but the Voyager probes (1980-1) showed that these are, in fact, made up of hundreds (possibly even thousands) of smaller ringlets.

Like Jupiter, Saturn is covered by thick cloud and swept by fierce winds. The latter are three times the speed of those on Jupiter – well over 1,000 mph at the equator – and storms can last for more than a year.

Saturn’s ‘day’ is only about 10 hours long, but its ‘year’ lasts almost 30 earth years.

Saturn has more moons than any other planet in the solar system – 47 at the latest count, of which 35 (as of 2004) have been named. The largest of Saturn’s moons, Titan, is bigger than both Pluto and Mercury. Several of the most recent discoveries break with tradition and instead of being named after figures from classical mythology are named after giants in Inuit legends – Ijiraq, Paaliaq, Siarnaq and Kiviuq.

Kiviuq (or Kivioq) incidentally, is not only the name of a mythical Eskimo giant but also a popular local dish made of dead auks sewn up in seal skin and left to rot for several months. It was the death of the Danish explorer Knud Rasmussen (1879-1933) who investigated Inuit life in the 1920’s, and who succumbed to salmonella poisoning after sampling some. His mother, who was herself Inuit, should have warned him.

Picture ideas:


Saturn: the planet or the god, probably both.

Unnecessary detail:

Saturn is composed of 92% hydrogen, 7.4% helium with trace elements of methane and ammonia. It is thought to have some sort of rocky core in there too.


s: Chambers Book of Facts
s: COH

Last edited by JumpingJack on Wed Mar 29, 2006 9:26 am; edited 3 times in total

62142.  Mon Mar 27, 2006 3:30 pm Reply with quote

"The density of Saturn is about 0.7% that of water. Though it's the second largest planet, after Jupiter, it is the least dense of them all the planets"

So, could you stand on Saturn, then? (Assuming you happened to be in the vicinity). I mean, is there something firm and planetty there to actually support you? Could you leave a footprint?

62145.  Mon Mar 27, 2006 4:51 pm Reply with quote

Hi Mat,

Sorry about that typo, which I've corrected.

I don't think you could stand on Saturn, no. It's gassy on the outside and then turns into liquid hydrogen and helium. This 'sea' is extremely deep, there's no 'land' anywhere.

I suppose you might be able to stand on the 'sea-bed' as it were, because they seem to think there's a rocky core somewhere. But it would be about as sensible as trying to stand at the centre of the sun.

The internal temperature of Saturn reaches 35,000F.

62158.  Mon Mar 27, 2006 6:16 pm Reply with quote

'Solar system' rather than 'Universe', perhaps?

62160.  Mon Mar 27, 2006 6:26 pm Reply with quote

Well, I'm trying to shunt it towards poo and away from astronomy. "Solar System" is more of a give away, don't you think?

What about:

Who is responsible for the largest floater ever discovered?

62163.  Mon Mar 27, 2006 6:35 pm Reply with quote

Where's the largest floater anyone has ever seen?

62165.  Mon Mar 27, 2006 7:16 pm Reply with quote

Getting there...

62179.  Tue Mar 28, 2006 4:03 am Reply with quote

Where's the biggest floater under the Sun?

62186.  Tue Mar 28, 2006 4:41 am Reply with quote

So ... if you can’t stand on it, what makes it a “planet”? If it’s just a load of gas, does its planethood depend on long-term integrity, or having an orbit, or is it just size ... ?

Dictionary isn't much help; Chamber’s defines planet as “in old astronomy, a heavenly body whose place among the fixed stars is not fixed: a body (other than a comet or meteor) that revolves around the sun reflecting the sun’s light and generating no heat or light of its own [Surely that should be “a” sun, not “the” sun?]: a satellite of a planet: an astrological influence vaguely conceived.

I like that last one. But what is “old astronomy”? Is there a “new astronomy”? And if so, what does it think a planet is?

If I was in charge of defining planets, which I'm not currently, I would exclude anything you couldn't land a flying saucer on for starters.

62196.  Tue Mar 28, 2006 5:19 am Reply with quote

The issue of how you define a planet is a live and controversial one, and the responsibility of a body called the IAU, I think. I believe that astronomers aren't much interested in the outcome, because it's likely to be more to do with tradition and not upsetting the lay audience than it is with science - ie at best it'll be arbitrary and at worst they'll just try to come up with a definition which includes Pluto but excludes all the other big rocks they keep finding.

In Dan Dare the inhabitants of Saturn either live in the cloud layer or float through the gassy central portion, if memory serves. They are huge, like giant manta rays. I hope this helps.

62197.  Tue Mar 28, 2006 5:22 am Reply with quote

Good suggestions Flashy, I'll change the question.

62200.  Tue Mar 28, 2006 5:25 am Reply with quote


But, hmm...

It makes it look a bit easy I think.

Anyone else got a view?

62445.  Wed Mar 29, 2006 8:10 am Reply with quote

Saturn's density is 70% that of water, not 0.7%.

It's roughly 0.7 grammes per cubic cm, whereas water is 1 gramme per cubic cm.

It's still less dense than water, so it's okay - I'm just being an accuracy pedant...

62447.  Wed Mar 29, 2006 8:11 am Reply with quote

Maybe 'How big is the biggest recorded floater?' - that way you don't have 'the sun' give it away.

62459.  Wed Mar 29, 2006 8:32 am Reply with quote

True, but I don't think it does give it away for two reasons:

1) 'under the Sun' is normally taken to mean 'anywhere', and

2) even if they did smell a rat they're unlikely to know the answer (and if they do, good luck to them, I say).


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