Why are NASA astronauts (still) lying?

[Zakalwe]

PMSL...he now reckons that the Hubble is fake

What a boy!

[Andromeda]

Didn't Heiwa think the same thing?

Presumably Solon did, too.

[Zakalwe]

Didn't Heiwa think the same thing?

Presumably Solon did, too.

It's crank magnetism at it's worst.

[raven]

I am not sure which is funnier, crank magnetism or crank factionalism, where the cranks declare blood feuds over differing versions of their 'theories'.

[cjameshuff]

Presumably Solon did, too.

Solon seemed to think everything that saw stars had "gratings", exotic optics and sensors, etc. A big part of his "theory" was that only these super-complex devices ever saw stars. Them being fake would undermine that. Though it wouldn't be the first idea he latched onto with that problem...

[Andromeda]

Ah yes, I'd forgotten about the gratings.

[ka9q]

In addition to the valid reasons given, people don't want to learn because learning is hard.

I think it's a little different. Sure, some people learn more easily than others but learning anything worthwhile can be a lot of hard work even for the smartest.

But I think there's something even more important than intelligence: motivation. Some people find learning intrinsically rewarding while others do not. I don't understand why there's such a difference but it seems to be real.

I've heard more than one Nobel laureate talk about how lucky they felt to have retained their childhood curiosity into adulthood. I think they're right; children are born to be scientists but we seem to beat it out of most of them.

Reminds me of one of my favorite movie exchanges:

Klaatu: You have faith, Professor.
Prof. Barnhardt: It isn't faith that makes a good scientist, Mr. Klaatu. It's curiosity.

[ka9q]

Not bad for 1961.

Well, sure. IMHO the best science fiction has always involved straightforward extrapolations of known science.

We didn't have to go to the moon to discover that you can't see stars in the daytime by naked eye. You only had to apply long-known physics and physiology to the question. Oh, and you have to know what questions to ask in the first place.

[Dalhousie]

Since we are mining older SF that got it right, here is Arthur Clarke's Earthlight (1955), p6-7.

The protagonist is travelling westward by lunar monorail when....

"There, marching across the sky in flaming glory, were the peaks of the Apennines, incandescent in the last rays of the hidden sun.  The abrupt explosion of light left Sadler almost blinded; he shielded his eyes from the glare, and waited until be could safely face it again.  When he looked once more the transformation was complete.  the stars, which until a moment ago had filled the sky, had vanished.  His contracted pupils could no longer see them..."

[smartcooky]

Since we are mining older SF that got it right, here is Arthur Clarke's Earthlight (1955), p6-7.

And a damn good story that one. Always thought it would make a great spy movie!

[Dalhousie]

Since we are mining older SF that got it right, here is Arthur Clarke's Earthlight (1955), p6-7.

And a damn good story that one. Always thought it would make a great spy movie!

Re-reading at present, it's amazing how much he got right.  It still works as a story and the theme of off-Earth resources is very contemporary.

[ka9q]

Yet Clarke, like so many others, got it wrong when he said that the protagonist's contracted pupils kept him from seeing the stars.

The iris has a very limited dynamic range. Most of the eye's dynamic range is in the retina, which changes its "film speed" depending on how much light strikes it. When you go into the dark your pupils dilate within seconds or even less (at least if you're young) but it takes tens of minutes for your retinas to replenish light-depleted pigments and become dark-adapted.

[raven]

It can make the difference between seeing stars and not seeing stars if your eyes are already partially dark adapted, such as if you are inside a room with the lights at night, and you go up to the window, blocking the room lights from view. I know I've seen stars under such circumstances.

[ChrLz]

If I can throw in some w-a-g figures (haven't googled, happy to hear more accurate numbers!), I'd take a stab that the contraction/dilation of the pupil gives around 5-6 f-stops worth, that when added to the retinas natural *instantaneous* range will give a total of about 9-12 f-stops range for normal, single scene viewing.

But if you then add the time for chemical adjustment - eg night adaptation and vice versa - I'm pretty sure it's up around 22 - 24 stops overall dynamic range.  Obviously that figure does not apply to a single scene, but covers the sort of range it has in total, given time to adjust and provided no stray light affects the adaptation (which is the problem on the Moon).

Interestingly, although it's impossible to compare eyes to cameras in a fair way, a good quality DSLR will also give about 9-12 stops of dynamic range for a given single scene..  and of course you can then tweak it and do various 'cheats' (change ISO and use Dark Frame Subtraction, use very large aperture lenses, use High Dynamic Range or Dynamic Range Optimisation, etc to also cover well over 22 stops ..

Smaller sensor cameras may only be closer to half that.

[Dalhousie]

Yet Clarke, like so many others, got it wrong when he said that the protagonist's contracted pupils kept him from seeing the stars.

The iris has a very limited dynamic range. Most of the eye's dynamic range is in the retina, which changes its "film speed" depending on how much light strikes it. When you go into the dark your pupils dilate within seconds or even less (at least if you're young) but it takes tens of minutes for your retinas to replenish light-depleted pigments and become dark-adapted.

It might not have been wrong based on what was known at the time