Reflecting cold

[Davey]

Tim Streater expressed it perfectly. It's a nonsense way of expressing a relationship, as I showed with the first part of the sentence.

[Martin Brown]

Your blood isn't at zero pressure though. Skin is actually a very strong elastic material and provided you remember to breathe out can easily tolerate being in zero pressure. The problem is with all the delicate orifices like ears which cannot adjust fast enough.

And drying of the surface of the eyeballs where there is free water exposed. Your skin only has to provide an overpressure of about 1psi to prevent your blood boiling.

decompression of a plane is perfectly survivable provided you remember to put the oxygen mask on and that at full cruise height represents losing almost 90% of the atmospheric pressure.

Slow leaks during high altitude flight are far more dangerous...

[Tim Streater]

If you mean in inter-galactic space, you'll cool down to 3K or whatever the temp of the background radiation is. I think you don't actually explode but fizz, rather.

Yes. The atmosphere is full of oxygen, a poisonous and extremely reactive gas. And don't say it isn't poisonous, because although we need it for life, life takes good care to ship it round the body extremely carefully, bound up in small packets inside haemoglobin. If you took away all the life processes that produce it, it's reckoned that it would all disappear within about a million years or so - the Earth would "rust", essentially.

So the Earth is far away from the equilibrium state that you would expect (wrong average temp, lots of a very reactive gas in the atmos). Clues to life.

Which is in fact why you don't need probes to land on Mars to look for life. Atmos: neutral gases like carbon dioxide. Average temp: what a black body's equilibrium temp would be at that distance from the Sun.

That's what James Lovelock says, anyway. [1]

[1] He of the Gaia Hypothesis (note the use of the word hypothesis) [2] [2] A strong proponent of nuclear power, and quite fed up with all the flower-power airy-fairy new-age do-gooders who have taken his Gaia idea and mis-interpreted it to mean that the rocks are alive etc etc.

[Martin Brown]

Photosynthesis actually works *against* the greenhouse effect CO2 is triatomic and a potent greenhouse gas whereas O2 is diatomic and is not. The very first plants by stripping the atmosphere of CO2 and CH4 made the planet cooler (and the original higher CO2/CH4 concentrations in part compensated for a weaker young sun). The oxygen pollution they produced initially forced soluble iron out of solution leading to some of the exteremely red oldest sedimentary rocks (and also mineable iron ore bodies).

This is very true. Finding O2 and CH4 in the same planetary atmosphere advertises interesting non-equilibrium chemistry (ie. possibly life).

He could well be wrong though. Methane emissions have now been observed in the Martian summers which is a big surprise when the surface is covered in superoxides and peroxides and illuminated by hard UV. It is now also known that dig down a bit and you find water and dry ice too.

don't think there is any way to resolve it without sending probes. It is unlikely to be more than a few microbes eking out a living in the permafrost. But wherever we have looked on Earth there have been some extremophiles living there albeit growing very slowly and hard to spot.

[Roger Chapman]

Unfortunately such practices are impossible to stamp out once the usage becomes common. There is some modern usage that doesn't actually make sense if you don't know the convention. I was reminded of the original meaning of 'port your helm' (turn to starboard) before it was turned on its head but thought I had best look it up before mentioning it and came across this:

"A steering wheel is usually connected to the rudder by cables and pulleys in such a fashion that the wheel, the rudder and the vessel all turn in the same direction."

Wheels, like control knobs, don't move in any direction, they rotate but common usage (or convention if you will) now dictates that turn to the right is clockwise and turn to the left anti-clockwise.

And don't get me started on Grid References ...

[Tim Streater]

I'm inclined to agree with you, actually. If nothing else, sending probes is *fun*.

IIRC Lovelock was asked by NASA to design an instrument for the Viking landers, to do an experiment looking for life signs. He suggested you could get the main thrust of it by doing spectroscopic analysis of Mars' atmosphere from here. The NASA klods were not amused.

[Roger Chapman]

If you out in space without an oxygen supply you would be dead very shortly anyway but even if the skin is strong enough to contain that which is more usually supported by 14.7lb/in^2 of air pressure there is a direct atmosphere/blood connection in the lungs where the blood could boil off.

Only if they aren't noticed. ;-)

[Tim Streater]

That's probably where you would fizz a little.

[Martin Brown]

That much he was right about, but it took until a couple of years ago for the remote sensors to become good enough to pick up the faint traces of methane on Mars. It may one day work at much greater distances too - at least for Earth like planets that are well out of equilibrium.

The favoured probe technique now on Mars will be to feed the critters isotopically marked food and then watch for signs of preferential uptake of light isotopes over any above inorganic rates.

This should avoid Viking like confusion where inorganic oxidisers could have been responsible for the CO2 signals they saw. I suspect that most tests will remain null or inconclusive unless we strike really lucky...

[Alan Braggins]

Rubbish. You might prefer that meaning to be expressed differently, but I suspect even you understand what is meant by it, and certainly it seems to be used with a consistent meaning.

(If you really don't understand it: "A is X times smaller than B" means the same as "B is X times larger than A" or "A is 1/X times the size of B".)

[Davey]

I saw some discussion that possibly linked the change of the convention to the sinking of the Titanic. Previously, pushing a tiller to the left (port) resulted in a movement of the ship to the right (starboard), and apparently early ships' wheels followed that convention, whereas the Titanic was one of the early ships to change to the system as described above. I am merely quoting a report, I have no idea if it's true or not. But it reflects your quotation; 'port your helm' (turn to starboard) before it was turned on its head.

Thank you for your support. I agree that the practice is becoming more and more common, unfortunately. I also now see in print the use of 'of' for 'have', which was surely first a spoken mis-use, but is now becoming more frequent. As in: "I could of done that differently". It makes me cringe. And as for the American 'gonna', which is invading these shores, Help!

I notice that nobody has yet commented on my interpretation of the relative sizes of Jim's and Tom's nether appendages.

[Chris J Dixon]

Indeed so. It has clearly been around for a while - I notice that my Word 2003 autocorrect is set up, by default, to remove many of these abominations. Nevertheless, it does surprise me how such poor language becomes common usage.

I have to accept that language is not static, but that does not mean that I cannot lament the passing of such distinctions as the difference between disinterested and uninterested.

Chris

[Chris J Dixon]

There is an interesting case where the way you express things has a significant impact.

Consider an item previously sold at £3, now reduced to £2. This is clearly a reduction of 1/3 (33.3%). The more cunning will say instead something like "Previously on sale at 50% more."

Chris

[Ian Jackson]

In message , Alan Braggins writes

Indeed. I'm often a bit picky about how English is used. However, in simple, everyday speech, "five times smaller" is perfectly logical, understandable and unambiguous. I'm sure it's the sort of thing I've heard many learned people say.

[dennis]

That's not American.. its been around here for at least 40 years. As in "I am gonna buy a new car"

[Ian Jackson]

In the movie, "2001", the computer (Hal) turns nasty, and starts bumping off the crew of the space ship. The last survivor, Dr. Frank Poole gets locked outside, in an EVA pod. Hal has locked all the doors, and the only chance Poole has of getting back in is to use the emergency airlock

- the only door which can be opened manually from the outside. Unfortunately, Poole has forgotten to take his space helmet. Nevertheless, he does make it back inside the ship. Find out how, in next week's thrilling episode of "2001: A Space Odyssey".

[Jules Richardson]

Are they completely flat, or do they have a corrugated appearance? My parents have the latter at their place (house also built in the 70s), and there aren't any back-fins, only the two brackets for securing to the wall.

cheers

Jules

[Roger Chapman]

Not completely flat. I suppose you could call them corrugated although their appearance has more in common with modern steel roofing sheets (-=-=-=-=-) than corrugated asbestos sheets. They also have distinctive header and footer reservoirs that roll top panels don't have.

[Roger Chapman]

snip

[Davey]

Has it been written as such for that time, or just spoken? America was where I first found it written down as normal speech, rather than spoken as lazy speech. And that was 30+ years ago.