Author Topic: Apollo and Stars  (Read 72768 times)

Offline JayUtah

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Re: Apollo and Stars
« Reply #120 on: October 19, 2015, 02:44:41 PM »
We move about the 3D world by instinct, mostly unconscious.  Reasoning about the 3D world consciously requires a set of cognitive skills that not all persons have developed sufficiently.
"Facts are stubborn things." --John Adams

Offline Jason Thompson

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Re: Apollo and Stars
« Reply #121 on: October 19, 2015, 03:17:44 PM »
I doubt he knows how to calculate it, let alone visualize it.

That's fine. "I don't know," is a perfectly acceptable answer (although looking up the method of calculating it is not hard). It's the evasion of the question I am calling him out on.

I can even reframe it: how big will an object that appears to be x degrees across at distance ykm appear to be from a distance 2ykm?
"There's this idea that everyone's opinion is equally valid. My arse! Bloke who was a professor of dentistry for forty years does NOT have a debate with some eejit who removes his teeth with string and a door!"  - Dara O'Briain

Offline Abaddon

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Re: Apollo and Stars
« Reply #122 on: October 19, 2015, 03:21:41 PM »
We move about the 3D world by instinct, mostly unconscious.  Reasoning about the 3D world consciously requires a set of cognitive skills that not all persons have developed sufficiently.
Fair point.

Offline bknight

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Re: Apollo and Stars
« Reply #123 on: October 19, 2015, 03:25:38 PM »
I doubt he knows how to calculate it, let alone visualize it.

That's fine. "I don't know," is a perfectly acceptable answer (although looking up the method of calculating it is not hard). It's the evasion of the question I am calling him out on.

I can even reframe it: how big will an object that appears to be x degrees across at distance ykm appear to be from a distance 2ykm?
Correct, but if he answered correctly he position is devastated, so I'm guessing he ducks and runs.
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
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Offline Jason Thompson

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Re: Apollo and Stars
« Reply #124 on: October 19, 2015, 04:19:49 PM »
Correct, but if he answered correctly he position is devastated, so I'm guessing he ducks and runs.

Maybe so, but if we continue to draw attention to the discussions he has abandoned his position becomes clearer to anyone who may come across these threads. It is often the hope that if the discussion moves on far enough the original unanswered questions will be forgotten. I'm not letting it go. I will continue to ask every day he posts until I get a satisfactory response. If he gets tired of seeing the same question over and over again he can engage or concede the point, but I am not letting it slip under the radar.
"There's this idea that everyone's opinion is equally valid. My arse! Bloke who was a professor of dentistry for forty years does NOT have a debate with some eejit who removes his teeth with string and a door!"  - Dara O'Briain

Offline ka9q

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Re: Apollo and Stars
« Reply #125 on: October 20, 2015, 03:08:05 PM »
Tarkus, does it not occur to you that the Sun moves across the Lunar sky?  I believe that the solar panel "chased" the Sun into the Lunar afternoon and stopped there.  Surveyor III could not be "awakened" after the 14 day cold-soak it received during the Lunar night, so the Solar panel remained where it was when the lander shut down.
That's exactly right -- you beat me to it. This is early local morning, so the sun is in the east. The photo is taken looking roughly northwest, so the solar panel is still pointed to the west where the sun set before the Surveyor died.

The Apollo 12 site is near the moon's equator in the moon's western hemisphere (west of the prime meridian that runs down the middle of the near side) so the earth is east of overhead. And because the earth remains almost stationary in the lunar sky, Surveyor's high-gain antenna still points in that direction -- the same direction as the high-gain S-band antenna in the background next to the Apollo 12 LM.

You know, I hadn't noticed that before. This is why I take the time to rebut hoaxers; I almost always learn or at least notice something new even though they never do.

Offline bknight

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Re: Apollo and Stars
« Reply #126 on: October 20, 2015, 03:28:25 PM »
Tarkus, does it not occur to you that the Sun moves across the Lunar sky?  I believe that the solar panel "chased" the Sun into the Lunar afternoon and stopped there.  Surveyor III could not be "awakened" after the 14 day cold-soak it received during the Lunar night, so the Solar panel remained where it was when the lander shut down.
That's exactly right -- you beat me to it. This is early local morning, so the sun is in the east. The photo is taken looking roughly northwest, so the solar panel is still pointed to the west where the sun set before the Surveyor died.

The Apollo 12 site is near the moon's equator in the moon's western hemisphere (west of the prime meridian that runs down the middle of the near side) so the earth is east of overhead. And because the earth remains almost stationary in the lunar sky, Surveyor's high-gain antenna still points in that direction -- the same direction as the high-gain S-band antenna in the background next to the Apollo 12 LM.

You know, I hadn't noticed that before. This is why I take the time to rebut hoaxers; I almost always learn or at least notice something new even though they never do.
And/or new information is derived by looking up information.  For example, until this thread I thought both of the upper panels were solar
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline Paul

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Re: Apollo and Stars
« Reply #127 on: October 20, 2015, 07:21:12 PM »
but photos like this there is no reason for that not a single star will not see:


Clouds cleared for a while tonight and nice 49% Moon which reminded me of tarkus' Earth image, so thought I'd post some examples of the effect "exposure" has on an image.

As we all know exposure is determined by ISO, shutter speed, and aperture. All the below images are ISO 800 and f/4.5. I have varied shutter speed to attempt to get some stars into the image. Focal length is 86mm.

So first up, with shutter speed 1/400 sec. This gives a nicely exposed Moon with lots of crater detail (see red inset), but of course the shutter speed is too fast to pick up stars.



Let's try a shutter speed four times longer, 1/50 sec:



Unfortunately we have now over-exposed the Moon, leaving only a little detail around the terminator. Again though, stars are not visible.

Finally, let's go for a really long shutter speed of 2 seconds (100 times longer than last time).



We have now totally blown the Moon out and lost all detail. But finally, we can see (a few) stars!

This illustrates why that photo of the Earth has no stars in it, to get the correct exposure for the Earth means using a fast shutter speed (for a given ISO and aperture) which means the faint stars are under-exposed and thus not visible.

Hope that helps you understand exposure now tarkus.
« Last Edit: October 20, 2015, 07:23:30 PM by Paul »

Offline bknight

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Re: Apollo and Stars
« Reply #128 on: October 20, 2015, 07:37:22 PM »
Nice demonstration, but I feel it will be lost on him.
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline gillianren

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Re: Apollo and Stars
« Reply #129 on: October 20, 2015, 07:52:11 PM »
It appears from what he's written that he believes atmosphere matters.
"This sounds like a job for Bipolar Bear . . . but I just can't seem to get out of bed!"

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Offline bknight

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Re: Apollo and Stars
« Reply #130 on: October 20, 2015, 08:13:40 PM »
It appears from what he's written that he believes atmosphere matters.
Of course we need it to breathe  ::)
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline ka9q

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Re: Apollo and Stars
« Reply #131 on: October 20, 2015, 08:39:04 PM »


We have now totally blown the Moon out and lost all detail. But finally, we can see (a few) stars!
And the earthshine illuminating the dark half also shows up quite nicely. Normally you can see that by eye only around new (or old) moon, when it's a thin crescent.

Offline Count Zero

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Re: Apollo and Stars
« Reply #132 on: October 21, 2015, 03:34:42 AM »


We have now totally blown the Moon out and lost all detail. But finally, we can see (a few) stars!
And the earthshine illuminating the dark half also shows up quite nicely. Normally you can see that by eye only around new (or old) moon, when it's a thin crescent.

Yes, for those of you just tuning-in, we have an actual photograph of the dark side of the Moon!!!1!
"What makes one step a giant leap is all the steps before."

Offline Ishkabibble

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Re: Apollo and Stars
« Reply #133 on: October 21, 2015, 07:41:20 PM »
Yes, for those of you just tuning-in, we have an actual photograph of the dark side of the Moon!!!1!

Hahahahahahahahahaha...
You don't "believe" that the lunar landings happened. You either understand the science or you don't.

If the lessons of history teach us any one thing, it is that no one learns the lessons that history teaches...

Offline tarkus

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Re: Apollo and Stars
« Reply #134 on: October 21, 2015, 09:32:50 PM »
Tarkus, does it not occur to you that the Sun moves across the Lunar sky?  I believe that the solar panel "chased" the Sun into the Lunar afternoon and stopped there.  Surveyor III could not be "awakened" after the 14 day cold-soak it received during the Lunar night, so the Solar panel remained where it was when the lander shut down.
That's exactly right -- you beat me to it. This is early local morning, so the sun is in the east. The photo is taken looking roughly northwest, so the solar panel is still pointed to the west where the sun set before the Surveyor died.

The Apollo 12 site is near the moon's equator in the moon's western hemisphere (west of the prime meridian that runs down the middle of the near side) so the earth is east of overhead. And because the earth remains almost stationary in the lunar sky, Surveyor's high-gain antenna still points in that direction -- the same direction as the high-gain S-band antenna in the background next to the Apollo 12 LM.

You know, I hadn't noticed that before. This is why I take the time to rebut hoaxers; I almost always learn or at least notice something new even though they never do.
If you look closely, both panels have identical lunar probe inclination in both photos ... too coincidental.




Moreover, if I wanted to make the most of a fixed solar panel, would place it parallel to the ground and not inclined as seen in the image.