Author Topic: Why are there no stars seen on the pictures of the moon?  (Read 42737 times)

Offline Commander Cody

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Why are there no stars seen on the pictures of the moon?
« on: November 11, 2012, 03:02:38 PM »
Why are there no stars seen on the pictures of the moon?

mabye it was the technology at that time or is their another reason?  :o ???Please explain.
Commander Cody.

Offline Andromeda

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #1 on: November 11, 2012, 03:14:36 PM »
Capturing stars on photographic film requires a long exposure.  The cameras were set to take pictures of a brightly lit landscape, which required a very short exposure - too short to pick up stars.

If the astronauts had used long exposures, the landscape would have been badly overexposed and the pictures would have been a big mess.  Remember, the mission was to survey the Moon - not take pictures of stars.

That's the same reason why pictures of the ISS or the shuttle in orbit, to name but two examples, do not show stars in the pictures.

Try it yourself - go out on a clear night when you can see lot of stars and take a snapshot.  Your camera won't image any stars.

http://www.clavius.org/photoexp.html

http://www.badastronomy.com/bad/tv/foxapollo.html#stars
« Last Edit: November 11, 2012, 03:17:08 PM by Andromeda »
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Offline Jason Thompson

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #2 on: November 11, 2012, 03:20:29 PM »
It's not the technology of the time. The same limitations on photographic results apply today. Stars are dim objects, especially when compared to sunlit scenes. You can't capture both on film at once.
"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 Commander Cody

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #3 on: November 11, 2012, 03:33:24 PM »
Thank you this is really helpful.
Commander Cody.

Offline raven

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #4 on: November 11, 2012, 03:40:58 PM »
The only way you could get stars in the sky and a properly exposed lunar terrain would be with a double exposure: masking out the lunar terrain, exposing for stars, then taking a much shorter exposure of the terrain.

Offline Echnaton

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #5 on: November 11, 2012, 05:53:25 PM »
Why are there no stars seen on the pictures of the moon?

mabye it was the technology at that time or is their another reason?  :o ???Please explain.
There are photos of stars taken from the moon.  Apollo 16 had a special camera to take images in the far ultraviolet, a range of light that is not visible on earth.
The sun shone, having no alternative, on the nothing new. —Samuel Beckett

Offline raven

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #6 on: November 11, 2012, 06:35:43 PM »
There are photos of stars taken from the moon.  Apollo 16 had a special camera to take images in the far ultraviolet, a range of light that is not visible on earth.
Some long exposure shots of the solar corona taken from Lunar orbit also show stars.

Offline ChrLz

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #7 on: November 11, 2012, 07:00:31 PM »
Thank you this is really helpful.
Our absolute pleasure.  But may I suggest that you really should first research this stuff for yourself (Google it, go to Clavius.org, search this site) and see if you can find the answers *before* posting so many questions on what are very basic and well-explained concepts...

You see, CommanderC, there are some very wicked/deluded people (thankfully only one or two, but they use multiple identities) who often come here and pretend to be genuinely asking these sort of questions, when really they are not who they seem, and are just here to troll.  So we tend to be a little wary of newcomers!

Anyway, assuming you are genuinely doing an assessment (note the correct spelling..), may I ask what the assessment is about?  Is the assessor happy for you to simply ask questions at a forum, or would s/he prefer you did some more rigorous research?

And do you believe that Apollo happened, as history records it?  If not, may I then ask what sources of 'information' you have used so far, and how you found them?

Just as a general comment, may I point out that one thing that you will find out about the very silly people who think Apollo was faked, is that they all have an astonishing inability to think beyond their own limited experience..  Let me give you a hint on what I mean by that, in the hope that *you* might do some of the required thinking.  On this 'star visibility' topic, ask yourself a few basic questions.

1. What, in terms of being able to see (or photograph) stars, is different about the lunar environment compared to viewing stars on Earth?  Why can't you see stars in daylight on Earth? (that isn't as stupid as it might sound..)

2. Is there a way to quantify and analyse those differences?

3. Is there any way to *usefully* simulate the differences, here on Earth?

4. Without a full knowledge of Q1, and without properly answering Q2 and Q3, would anything you might simply guess, be of any validity whatsoever?


Hint, the answer to Q.4 is NO.  But the typical Apollo denier very ignorantly thinks otherwise - please do not become one of them...

BTW, similar questions can be asked about things like the dust on footpads - see if you can spot why Apollo deniers get caught out by their inability to understand the lunar environment and why 'odd' things seem to happen.  They are only odd if you don't (or don't want to) understand.

Offline Count Zero

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #8 on: November 11, 2012, 11:43:54 PM »
Why are there no stars seen on the pictures of the moon?

mabye it was the technology at that time or is their another reason?  :o ???Please explain.
There are photos of stars taken from the moon.  Apollo 16 had a special camera to take images in the far ultraviolet, a range of light that is not visible on earth.

Here are some of the photos of stars, taken from the lunar surface.  Note that the exposure times vary from several seconds to several minutes, whereas the images of the lunar surface, taken by the astronauts used an exposure time of 1/250th of a second.
"What makes one step a giant leap is all the steps before."

Offline ka9q

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #9 on: November 12, 2012, 12:17:41 AM »
Why are there no stars seen on the pictures of the moon?
Can you see stars in the daytime?

Sirius is the brightest star in the nighttime sky, yet it is still literally billions of times dimmer than the Sun. Why would you expect stars to show up in daytime photographs?


Offline Count Zero

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #10 on: November 12, 2012, 01:18:22 AM »
Can you see stars in the daytime?

Sirius is the brightest star in the nighttime sky, yet it is still literally billions of times dimmer than the Sun. Why would you expect stars to show up in daytime photographs?

Funny you should mention that.  Just last week I found myself outdoors a little while before dawn.  As is my habit,, I looked for and found Venus.  Jupiter was also easy to find.  Sirius was still visible.  Using it as a guide, I also found Rigel & Betelgeuse.  Interestingly, I could not see Aldebaraan despite its proximity to Jupiter.  This established a lower limit* to what magnitude I could see.  As the sky brightened, I first lost Betelguese (due, I think to the low contrast between it and the pink sky) then Rigel.  Sirius was extremely faint, and I couldn't look away without losing it.

Unfortunately, I had to cut the experiment short before sunrise.  In the past when I have done this experiment, I have been able to see Mars and Saturn with my naked eye for a little while after sunrise.  In both cases, I eventually had to look away and could not regain them in the brightening sky.

It's a fun exercise to try if you ever find yourself outside before dawn with time to kill.   8)

*Upper limit?  Goddamn Pogson...
"What makes one step a giant leap is all the steps before."

Offline Zakalwe

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #11 on: November 12, 2012, 02:48:20 AM »
Heres a photo that I took of the Singapore skyline a good few years ago. It was taken in the early hours of the morning.



See the almost complete lack of stars in the sky, even though the sky is clear (there's a couple of clouds scudding by but the rest of the sky is clear)?

The exposure length? 13 seconds.

Now do you wonder why you can't see stars in shots taken from the surface of the Moon in the bright light of the Lunar morning, with the Sun reflecting off the Lunar surface and astronaut's suits? Especially when you consider the shutter speed (fractions of a second).

Anyone who has ever used a camera will know instinctively why there's no stars in the Lunar photos. I find it almost unbelieveable that the "no stars" claptrap keeps getting regurgitated time after time.
"The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that 'my ignorance is just as good as your knowledge.' " - Isaac Asimov

Offline ka9q

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #12 on: November 12, 2012, 07:03:26 AM »
What was the f-stop and sensor speed?

Offline ka9q

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #13 on: November 12, 2012, 07:10:47 AM »
Venus at brightest: -4.9. That's bright.
Venus, full: -3.8.
Jupiter: -1.6 to -2.94.
Sirius: -1.46
Rigel: +0.12
Betelgeuse: +0.3 to +1.2
Aldebaran: +0.75 to +0.95

That probably explains a lot.


Offline smartcooky

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Re: Why are there no stars seen on the pictures of the moon?
« Reply #14 on: November 12, 2012, 07:15:49 AM »
Anyone who has ever used a camera will know instinctively why there's no stars in the Lunar photos. I find it almost unbelieveable that the "no stars" claptrap keeps getting regurgitated time after time.

Dealing with photographic images is something I do on a daily basis at work.

If I saw images like this in the Apollo record...



...instead of like this...



...the alarm bells would start ringing very loudly indeed.

If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.