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CzC
2002-Jul-15, 01:30 AM
I got a minor debate going on with a buddy of mine. Although he claims he's not a full-blown hoax believer, he says he has his doubts. The following pic is from Apollo 13 and he thinks that the bright spot is caused by artficial lighting, since the earth's atmosphere wouldn't create a 'hotspot' from that distance. I'm thinking it's not a hotspot, but maybe a reflection from inside the CSM, or some other photographic anomaly I'm not aware of.

Any thoughts?

http://www.business.uab.edu/cache/images/as13-66-8591.jpg

Ian R
2002-Jul-15, 02:18 AM
I believe that the 'hotspot' in the middle of the ocean really is a specular reflection of the Sun. It's most certainly a natural occurrence and a similar effect can be reproduced using a billiard ball and a flashlight.

Karl
2002-Jul-15, 02:20 AM
Download the AVI of the Galileo earth encounter and you will see the same effect. You also see it on shuttle video. I believe it is sun glint from water surfaces.

http://www.solarviews.com/cap/earth/earthgal.htm

AstroMike
2002-Jul-15, 02:35 AM
You can also observe it in this Blue Marble animation (http://earthobservatory.nasa.gov/Newsroom/BlueMarble/Images/rotate_320.mpg) too.

David Hall
2002-Jul-15, 03:08 AM
It's amazing to me how things you can see close-up can also be seen in larger scales. I'm talking specifically about reflections on water. I've seen the glint of reflection on small ponds or such, and it looks very natural. But I was very surprised to look out of the window of a trans-Pacific flight and see the exact same kind of reflection from 30,000 feet up.

So if you go up to higher vantage points and larger scales, you should be able to see exactly the same thing. And that's what I think this photo is. The only difference I can see is that at this scale, the curvature of the Earth becomes a major factor, and so the reflection comes out as a point rather than the linear reflection you get from a flat surface.

It's like what Ian said with the cue-ball. A perfectly natural reflection on a reflective sphere from a perfectly natural light source. Just because the scale is different, doesn't mean the phenomenon has to be.

CzC
2002-Jul-15, 05:13 AM
On 2002-07-14 23:08, David Hall wrote:
It's amazing to me how things you can see close-up can also be seen in larger scales. I'm talking specifically about reflections on water. I've seen the glint of reflection on small ponds or such, and it looks very natural. But I was very surprised to look out of the window of a trans-Pacific flight and see the exact same kind of reflection from 30,000 feet up.

So if you go up to higher vantage points and larger scales, you should be able to see exactly the same thing. And that's what I think this photo is. The only difference I can see is that at this scale, the curvature of the Earth becomes a major factor, and so the reflection comes out as a point rather than the linear reflection you get from a flat surface.

It's like what Ian said with the cue-ball. A perfectly natural reflection on a reflective sphere from a perfectly natural light source. Just because the scale is different, doesn't mean the phenomenon has to be.



I didn't think it was because of scale, I thought the atmosphere would have diffused the light to the extent where it wouldn't reflect like that. This is the first earth shot where I noticed the hotspot. I learnt sumthin'.

Another reason why I didn't think it was the sun was because the terminator was at half earth. I thought you wouldn't be able to see the reflection if the sun (flashlight) was 90 deg. from you, but you do, exactly where it is in this pic.(cue ball & flashlight exp.).

Thanks,
CzC

David Hall
2002-Jul-15, 06:24 AM
Well, the atmosphere is only an egg-shell thickness compared to the size of the Earth, so there really isn't that much there to defract. Heck, look at the limb of the Earth in the photo, you can hardly tell the atmosphere is there. /phpBB/images/smiles/icon_smile.gif

When you think of it, the position of the reflection is at the point where the surface is at an exact 45° angle between you and the Sun, so it's at exactly the point it should be also.

I'm glad you tried the experiment to verify it though.

As a matter of fact, I'm looking at my inflatable globe right now, and it has a reflection from the light coming from the window behind me that's almost exactly like the one in the Galileo video. A perfect angle from the source to me. /phpBB/images/smiles/icon_biggrin.gif

johnwitts
2002-Jul-15, 09:56 PM
http://www.business.uab.edu/cache/images/as13-66-8591.jpg

I look at this photo every day. It's the wallpaper on my desktop. It's flipped vertically to avoid fouling the icons.

I noticed an anomoly with this photo. The Terminator is at 90 degrees and the 'hotspot' is at about 45 degrees. This is wrong if we assume we can see the whole of the sunlit portion of the Earth. We'd expect either the Sun to be 90 degrees to the right, leaving the 'hotspot' on the right limb of the Earth, or, if the 'hotspot' is correct, we'd expect the Earth to be about 3/4 lit.

If we look at the terminator, we can see that it is hardly sharp. Near the top there is a dark intrusion onto the dayside. All along the terminator is a zone of darker colouring.

I believe that when the picture was taken from the window, part of the Earth was obscured by the edge of that window, and being out of focus, produced the fuzzy darkened edge. It's similar to the effect seen in Bart Sibrel's 'secret' footage.

<font size=-1>[ This Message was edited by: johnwitts on 2002-07-15 17:58 ]</font>

David Hall
2002-Jul-16, 04:03 AM
On 2002-07-15 17:56, johnwitts wrote:

I noticed an anomoly with this photo. The Terminator is at 90 degrees and the 'hotspot' is at about 45 degrees. This is wrong if we assume we can see the whole of the sunlit portion of the Earth. We'd expect either the Sun to be 90 degrees to the right, leaving the 'hotspot' on the right limb of the Earth, or, if the 'hotspot' is correct, we'd expect the Earth to be about 3/4 lit.

Nope, I beg to differ. I just tried the experiment with my globe, placing the light source at a 90&deg; angle to my line of sight, and the reflection came up at 45&deg;, exactly like in the photo. Try it yourself. The hot spot is exactly where it should be on a quarter-full globe.

However, I do see your point about the terminator. Something doesn't look quite right to me, especially that shadow spur below the pole. But it may just be a trick of the exposure or something. It's possible it could be covered by the edge of something, but I don't think so. Didn't the CSM's have round windows?

David Hall
2002-Jul-16, 04:14 AM
BTW, I just found the photo on the ALSJ, and whatever the source is of the image above, they got the number wrong. The link incorrectly gives it as AS13-66-8591. The actual photo is:

http://www.hq.nasa.gov/office/pao/History/alsj/a13/as13-60-8591.jpg

There's nothing special in the photo comments, just View of Earth from Apollo 13.

infocusinc
2002-Jul-16, 04:21 AM
My guess would be that the darkness you see at the pole is just a thin area in the cloud cover at that point.

Also I think the gradation of the terminator is more easily seen in this area of the image since it is over a large mass of highlight tones. The rest of the terminator passes over darker areas of the earth and that makes seeing the gradation much harder.

<font size=-1>[ This Message was edited by: infocusinc on 2002-07-16 00:24 ]</font>

<font size=-1>[ This Message was edited by: infocusinc on 2002-07-16 00:25 ]</font>

Peter B
2002-Jul-16, 04:39 AM
Well, IMHO, I don't think that dark spur near the top of the photo is thinner cloud. Thinner cloud elsewhere in the photo doesn't look the same, and it wouldn't have such straight sides.

Rather, I think it's an object in the cabin which happened to float or intrude into the line of sight of the camera.

David Hall
2002-Jul-16, 04:46 AM
I think I agree with Peter B. There's something in the camera view there, an arm or camera-strap or something. I don't think its something that cuts off the whole terminator, just intrudes on the top half of it. You can see how it seems to bulge out a bit in the top half, as well as causing that spur.

infocusinc
2002-Jul-16, 04:47 AM
Peter,

You could be right. But the other areas of thinning clouds are not falling on the gradation of the terminator. Like I said...its just my guess /phpBB/images/smiles/icon_smile.gif

Ian R
2002-Jul-16, 01:15 PM
Here's a good picture from Apollo 8 to study in comparison with the Apollo 13 image:

http://www.hq.nasa.gov/office/pao/History/alsj/a410/AS8-15-2561.jpg

Ian R
2002-Jul-16, 01:26 PM
Apollo 11 B&W view:

http://www.hq.nasa.gov/office/pao/History/alsj/a11/AS11-38-5728.jpg

Kaptain K
2002-Jul-20, 12:20 AM
As to the "spur", it doesn't look the least abnormal to me. Think "cold front". A towering mass of cumulo-nimbus clouds near the terminator casting long shadows and then another cloud mass just before the terminator.
Look at the area just below and to the left of the "spur" and imagine what it would look like a couple of hours later at sunset.
_________________
When all is said and done - sit down and shut up!

<font size=-1>[ This Message was edited by: Kaptain K on 2002-07-19 20:24 ]</font>

David Hall
2002-Jul-20, 02:32 PM
I wonder if there's some confusion over just where the "spur" is. There's a solid dark shape sort of like the profile of a thumbtip pointing upwards next to the cloud bank. That one to me looks like it's probably natural and a consequence of the cloud shapes that form it. Ian R's links seem to bear me out here.

But there's also a fuzzier, lighter downward pointing shape over the ice-field of the north pole. That one doesn't look natural to me. It looks like an out-of-focus something in front of the lens.

Combine it with the other spur shape and it seems to lend a kind of bulge along the terminator there, though I think now that that is just an optical illusion.

David Hall
2002-Jul-20, 02:52 PM
You know, there was another thing I was wondering about this photo. Is that actually the north pole there? Since there are no visible land-masses to give us orientation, mightn't it be inverted and that's really the south pole there? Since A-13 flew in April both poles would have been roughly equally lit at that time. I don't know what the return trajectory was like, so I'm not sure what the camera angle would have been.

I'm thinking it's probably the north pole, but now I can't stop wondering. /phpBB/images/smiles/icon_confused.gif

JayUtah
2002-Jul-20, 11:22 PM
It might very well be the south pole. The typical hybrid trajectory went under the ecliptic.

GrapesOfWrath
2002-Jul-21, 01:55 AM
Which way are the clouds swirling? :)

Or is the photo reversed?

Questions to ponder on a cold July winter night.

therealdeal
2002-Jul-21, 07:09 AM
people need to realize that it could just be a whale. sometimes whales grow to be hundreds of kilometers long, or it could be a sea bird. flying looking for some whales to eat. Birds that large would need to eat whales, but it really is a paradox because whales can't fly.

Ian R
2002-Jul-30, 12:06 AM
This is another scan of the same photograph, and although the resolution is much lower, the "spur" doesn't seem to be visible:

http://www.lpi.usra.edu/research/apollo/images/AS13/60/8591.jpg

Here are all of the other Apollo 13 pictures from the same magazine:

http://www.lpi.usra.edu/research/apollo/bin/catalog/magazine.html?60

(Many thanks to 'Fly Me To The Moon' for providing the links to this great site.)

2002-Jul-30, 01:34 AM
<a name="20020729.5:25"> page 20020729.5:25 aka YES?yes
On 2002-07-14 21:30, CzC wrote: To: HUb'
5:25 P.M. after many years of not gettingthe pic{$}
I did find a way [by replying with a Quote]
Any thoughts? ::: i can remove the img parts and make a link to download

http://www.business.uab.edu/cache/images/as13-66-8591.jpg

Not that i will mind you::
BUT I DID .. find a way to do this [ hip hip do a Flip ] !!.!

Ian R
2002-Jul-30, 02:33 AM
Congrats!!

CzC
2002-Jul-30, 08:24 AM
What are the chances that this could be the 'spur'? It's from Apollo 15 but what is it? Got it from that site Flymetothemoon posted.

AS15-96-13039 (http://www.lpi.usra.edu/research/apollo/images/AS15/96/13039.jpg)
http://www.lpi.usra.edu/research/apollo/images/AS15/96/13039.jpg

CzC

AstroMike
2002-Aug-03, 05:04 AM
I'm not sure what that is. Does anybody else know?

JayUtah
2002-Aug-03, 07:37 AM
I honestly haven't had the time to research it. I finally got a day job building huge Linux computing clusters, and I'm in a play that's in the final week of rehearsal preparing for a six-week run.

Obviously the photo was taken from the CM, and that limits what can legitimately appear in the photo. It would have to be some part of the CM, but it doesn't resemble any part I can name right off. I'd have to go look at some blueprints, and I don't have the time right now.

Donnie B.
2002-Aug-03, 01:50 PM
Hmmm...

Flush lever for the Space Loo?

Actually it looks like one end of a handhold or equipment rack handle... if there were any such things near the CM windows.

Joe Durnavich
2002-Aug-03, 02:23 PM
As a guess, I would say it is the end of one of the boom arms of the satellite they deployed on 15. But I didn't think the arms were extended until the satellite was released.

johnwitts
2002-Aug-03, 02:58 PM
Looks like the Loch Ness Monster if you ask me! /phpBB/images/smiles/icon_smile.gif

NasaStooge
2002-Aug-03, 03:06 PM
It looks to me like the 'EVA floodlight' :
http://www.apollosaturn.com/modeling/csm/detail12.gif


link (http://www.apollosaturn.com/modeling/csm/detail12.gif)

circled in red here:

http://www.nasastooge.fsnet.co.uk/images/as15-88-11961-cropped.jpg

Original (http://www.hq.nasa.gov/office/pao/History/alsj/a15/as15-88-11961.jpg)



<font size=-1>[ This Message was edited by: NasaStooge on 2002-08-03 11:15 ]</font>

(Code fix)

<font size=-1>[ This Message was edited by: NasaStooge on 2002-08-03 11:17 ]</font>

NasaStooge
2002-Aug-03, 03:20 PM
On 2002-08-03 11:06, NasaStooge wrote:
It looks to me like the 'EVA floodlight' :
http://www.apollosaturn.com/modeling/csm/detail12.gif

link (http://www.apollosaturn.com/modeling/csm/detail12.gif)

circled in red here:

http://www.nasastooge.fsnet.co.uk/images/as15-88-11961-cropped.jpg

Original (http://www.hq.nasa.gov/office/pao/History/alsj/a15/as15-88-11961.jpg)



<font size=-1>[ This Message was edited by: NasaStooge on 2002-08-03 11:15 ]</font>

(Code fix)

<font size=-1>[ This Message was edited by: NasaStooge on 2002-08-03 11:17 ]</font>

CzC
2002-Aug-04, 08:46 AM
It looks to me like the 'EVA floodlight':

At the risk of sounding stupid, I'm gonna ask this. Why would the CM need an EVA floodlight?

CzC

kucharek
2002-Aug-04, 08:54 AM
On 2002-08-04 04:46, CzC wrote:

It looks to me like the 'EVA floodlight':

At the risk of sounding stupid, I'm gonna ask this. Why would the CM need an EVA floodlight?

CzC


On Apollo 15, 16 and 17 EVA's were performed during trans-Earth coast to retrive film canisters from the SIM bay in the SM. EVA was also always a contingency in case docking failed after the return of the LM from the Moon. In this case, the two astronauts would have to transfer from the LM to the CM by EVA.

Harald

GrapesOfWrath
2002-Aug-04, 09:59 AM
On 2002-08-03 11:06, NasaStooge wrote:
circled in red here:

SNIPPED IMAGE

Original (http://www.hq.nasa.gov/office/pao/History/alsj/a15/as15-88-11961.jpg)

Yeah, look at that "shadow" underneath the CM. If you go to the original image, it looks like it's actually an out-of-focus arm also. Just like in the OP!

Donnie B.
2002-Aug-04, 11:04 AM
Yes, that shadow is an out-of-focus something, but of course that something is attached to the LM rather than the CM -- probably inside, since I don't know of any exterior attachments likely to be in frame for that picture, if it's taken from either front window. If it's taken from the rendezvous window, it could be an antenna.

Andrew
2002-Aug-04, 12:21 PM
It's either the docking reticle or the landing point designator:
http://www.apollosaturn.com/modeling/lmdiagrams/frontwin.gif

http://www.apollosaturn.com/modeling/lmdiagrams/topwin.gif

There was quite a hilarious discussion on Apollohoax about this, where one of the JFK Researchers thought it was a shadow of a lighting gantry rig. It was of course the markings on the CDR's window taken from the inside of the LM.

johnwitts
2002-Aug-04, 01:33 PM
From ALSJ...

http://www.hq.nasa.gov/office/pao/History/alsj/a15/as15-96-13040.jpg

AS15-96-13040(37k)
LM Ascent Stage and EVA floodlight during rendezvous. Scan by Kipp Teague.

Guess he'd know.

JayUtah
2002-Aug-05, 03:53 AM
Yep, gotta be the EVA floodlight. Interesting, I wasn't looking for anything on the SM. Since all the CM windows look either outward or forward, it's hard to say that you could see any part of the SM from inside the CM. However, the light seems to stick out far enough to be seen. Thanks to those who posted the images.

CzC
2002-Aug-05, 06:27 AM
On 2002-08-04 23:53, JayUtah wrote:
Yep, gotta be the EVA floodlight. Interesting, I wasn't looking for anything on the SM. Since all the CM windows look either outward or forward, it's hard to say that you could see any part of the SM from inside the CM. However, the light seems to stick out far enough to be seen. Thanks to those who posted the images.



Do you think the EVA floodlight is what's seen as the 'spur' in AS13-60-8591 (http://www.hq.nasa.gov/office/pao/History/alsj/a13/as13-60-8591.jpg)?

CzC

jrkeller
2002-Aug-05, 10:09 PM
Here's another good one of the light

http://grin.hq.nasa.gov/IMAGES/SMALL/GPN-2002-000069.jpg