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Gillianren
2005-Feb-12, 02:59 AM
I stepped outside tonight to go to the mailbox, and there, hanging in the western sky, was a double crescent moon. the lower crescent was brighter and bigger, and above it was a thinner, paler, more detailed crescent.

of course, the first thing I did was point it out to a neighbor, just to make sure I wasn't seeing things. she and her kids confirmed that, yes, there it was, and no, I wasn't blind or crazy. (mentally ill is a different discussion.)

so what causes this? it's clear out tonight--very clear and a bit chilly. I'm in Olympia, WA, in a part of town that's pretty suburban--but since I've never seen it before, I don't think it's an effect from the street lights. is it?

Ilya
2005-Feb-12, 03:20 AM
It's a mirage.

A mirage is light refracting through layers of air with sharply different temperature, and can make objects appear not where they actually are. You were seeing a real Moon, and its refracted image above.

skrap1r0n
2005-Feb-12, 03:36 AM
gah, I wish you had a camera, that would have been quite a site.

Gillianren
2005-Feb-12, 04:27 AM
I knew it was a mirage--all I wanted to know was how it was formed.

I wish I'd had a camera, too.

Evan
2005-Feb-12, 04:41 AM
Dang, all the best pic opportunities happen when you don't have a camera on hand.

BTW, I see you don't capitalize over here either. :D

George
2005-Feb-12, 05:09 AM
I had no luck googling for a picture of a double moon.

how about a double sun? here (http://www.sundog.clara.co.uk/atoptics/sundoub.htm) 8)

The Bad Astronomer
2005-Feb-12, 07:43 PM
As an aside, I recently bought a small digital camera, and I carry it everywhere. The one time I didn't I was walking out of my office, and a very large opossum was staring at me. So now I stick it in my coat/shirt pocket and try not to miss opportunities.

BTW, getting a picture of something like the Moon is difficult unless you have a very powerful zoom. The Moon is a lot smaller than you think.

Normandy6644
2005-Feb-12, 08:55 PM
The Moon is a lot smaller than you think.

But it looks so big! :lol:

Andromeda321
2005-Feb-12, 11:19 PM
Yeah, Normandy, I thought it got bigger when it was closer to the horizon and smaller further up... :wink:

Evan
2005-Feb-12, 11:39 PM
For some perspective, the full moon is the same apparent size as a US quarter coin at a distance of 9 feet.

frogesque
2005-Feb-13, 12:32 AM
Not through a 400mm telephoto it's not :) (could do with a doubler though :lol: )

Evan
2005-Feb-13, 03:22 AM
Taken an hour ago.

http://vts.bc.ca/pics/moonfeb12051.jpg

frogesque
2005-Feb-13, 09:58 AM
That's a beauty Evan. =D> Was it a single shot or a stacked image?

Evan
2005-Feb-13, 11:52 AM
Very crude. A single shot taken with my Canon held by hand to my 6" f5 scope stood on my wobbly back deck. Image taken afocal with a 35mm plossl. I must make an adapter,

Philippe
2005-Feb-14, 05:27 PM
Was it a single shot or a stacked image?

Ok, I'm going to ask a question, thus proving that I'm as ignorant as I look.
:wink:

What is a stacked image?

And, Evan, a truly beautiful picture.

Evan
2005-Feb-14, 05:33 PM
Philippe,

Check here. (http://www.astrostack.com/)

Philippe
2005-Feb-14, 05:39 PM
Thank you.

Neat tool.

jfribrg
2005-Feb-14, 08:00 PM
BTW, getting a picture of something like the Moon is difficult unless you have a very powerful zoom. The Moon is a lot smaller than you think.

Can't you just wait till it is near the horizon when it is much larger? (runs away before anyone can hurl a tomato)

Philippe
2005-Feb-14, 08:24 PM
#-o

Donna and/or David
2007-Aug-17, 02:57 PM
this is Donna writing.... I was so glad to find this site/forum. Last night (Aug 17)and the night before my husband and I saw a double crescent moon - In all the looking up we have done in our lives this is a first for us. Interesting that the same optical effect was occurring both on the west coast and the east coast.

This leads me to ask - as did Gillian - what EXACTLY would do this - especially what would do it that would cover the USA like this. I can imagine local fronts, inversions, hot air, cold air combinations could do it. But clearly the AIR Gillian was looking through and the air David and I were looking through was not the same air.

dum dum daaaaaaammm -- OR - was it??:eek:

Swift
2007-Aug-17, 03:09 PM
Donna,
First, welcome to BAUT. I assume you are one of two people sharing an account (you know, you could each have your own ;) ).

Second,
Please note the date of Gillian's post, it was over two years ago. So the effect wasn't on both coasts at the same time, it was the same effect seperated in both time and space.

By the way, in the wikipedia entry on mirages (http://en.wikipedia.org/wiki/Mirage) there are no moon mirages, but several photos of sun ones, and a comet mirage

If the other expanations in this thread don't answer your question, please let us know.

Donna and/or David
2007-Aug-17, 04:30 PM
Yes indeed - about 10 minutes after posting that I noticed the date. I found one other mention of double cresent moons on line - it also happened in 2005 but elsewhere and elsewhen - on the 12th of February. I have e-mailed that person to find out here WHERE -- then I think I will check out the weather at each place. There may not be moon mirages exactly but there does have to be some sort of optical thing going on. It was too weird for us not to try to figure out in some way. I DID have a cel phone with camera but did not even think of trying to get an image.

David does not have his own post - because David does not DO web. So I am the family serfer person - both officially and by personal prediliction and inclination (surely one of those two words is properly spelled. I don't DO spelling). He does like the availability of information --

If David and I ever come up with a specific explanation that can be stated in scientific terms - I will be back here to post it!!

Glutomoto
2007-Aug-18, 03:18 AM
Thanks to astigmatism, I can see a double moon any time. :)

I found a double moon report from 1989, the image shown is a drawing and not a photo, and there is still no explanation. That person used some handy tools to verify that it was not a vision problem. link to science-frontiers.com Double Image Of Cresent Moon (http://www.science-frontiers.com/sf068/sf068g14.htm)

I found a couple of other images of a double moon, but one was r-rated and the other x-rated, so I won't link to them.

:)

p.s.
I take that back, refaction is listed as the usual cause.

ddesmonts
2007-Dec-05, 02:01 PM
Took the dog for a walk around 6:30 AM in Norwalk, CT and I looked up to see a crescent moon that had a double or stuttered look to it. There was also a VERY bright star just above and to the left of the monn (left of the convex edge). I thought I was nuts too, but it seem they've been seen by others.

So refraction is the cause? It was pretty clear out.

Kaptain K
2007-Dec-05, 04:18 PM
Welcome to BAUT ddesmonts.

No offense. Just out of curiosity.Why, for your first post, did you dig up a a thread that was not only over two years old, but hadn't been posted on in over four months?

As I said, no offense intended. You are not alone. Many come here and for their first post, reply to some long lost (and often, forgotten) thread. I've been here for ever (since before the merger) and I don't think I could even find a thread that old!

ddesmonts
2007-Dec-05, 08:10 PM
This was the only site and topic that spoke of a double crescent moon that I could respond to and ask about what I saw this morning.

Maksutov
2007-Dec-06, 01:25 AM
Kaptain K, please note that the post prior to ddesmonts post was August 17, 2007.

Welcome to the BAUT, ddesmonts!

Read the FAQs (http://www.bautforum.com/faq.php?faq=vb_faq), especially the rules (http://www.bautforum.com/about-baut/32864-rules-posting-board.html#post564845), and have fun.

Kaptain K
2007-Dec-06, 01:34 AM
Kaptain K, please note that the post prior to ddesmonts post was August 17, 2007.
OK, three months. Mea culpa!

Maksutov
2007-Dec-06, 01:55 AM
OK, three months. Mea culpa!LOL!

I don't mind "old" threads if the original is old but there has been recent activity, and if the total number of posts is something manageable. But when a one-liner is stuck on to the end of a 100+ post thread whose former terminus was, e.g., one to four+ years ago, it can be a real pain.

hhEb09'1
2007-Dec-06, 02:00 AM
I don't think I could even find a thread that old!Search is not that bad :)

Hey, what happened to the thread review feature. O, I guess it's not there for just replies? No, that's not it.

Donna and/or David
2007-Dec-06, 05:29 PM
OK - now I am not knowledgable about these thread words etc -- I just know that MOST of the posts on this one were NOT about the main topic - the view of a doubled crescent moon. AND frankly I was really interested to find someone else listing here about that. IF those other NON crescent posts had not been made this would be a short little thread - documenting these apparently very rare sights - and I thought that was the idea of this type of site -

Just my 2 cents. Since both my husband and I saw the sight posted in August - we know what we saw was VISIBLE to multiple people. So as a scientist, I think it is interesting that there is someplace to record such things even when the additions to the thread are months and months apart.

Have I missed something relevant here about why it is BAD to post to an OLD thread when that thread is the ONLY ONE about what interests you?

hhEb09'1
2007-Dec-06, 06:49 PM
Have I missed something relevant here about why it is BAD to post to an OLD thread when that thread is the ONLY ONE about what interests you?Checking back through, I don't think anyone said it was bad. Kaptain K was just surprised I think. I like to look back over some of the old material, see some of the old faces.

Welcome to BAUT, hope you stay awhile :)

Kaptain K
2007-Dec-06, 07:36 PM
Kaptain K was just surprised I think.
Exactly!
If I saw something I didn't understand, I "might" check the first page of posts, but I would probably just start a thread to ask.

Centaur
2007-Dec-06, 11:12 PM
About twelve years ago I started noticing that a thin crescent Moon had a ghost double. I visited an optometrist and learned I had astigmatism. Glasses eliminated the second Moon.

Glom
2007-Dec-08, 09:00 AM
That's a nice pic. I still only have my 35mm and would not use a DSLR enough for to make even remotely worth the money. I know you can get 35mm photos developed onto a CD rather than printed these days so I might try that though I need to find a new place that with develop astrophotos with the loving care required.

Donna and/or David
2007-Dec-10, 04:05 AM
THREE POINTS:

1. re ... I "might" check the first page of posts

I had googled "double crescent moon" - and this is the connection I got. It kind of depends on how you get into a system how you think to utilize that system - I posted in August of this year because it was one of only 2 places that came up as REAL sightings of this phenomenon. The more recent posted did so I belive for the same reason. Perhaps had we entered the system in a different way we would not have done so - but then I am not monitoring the whole site - just this thread.

2. Dec 8 at 9 AM member 777 Geek made an entry on this thread referring to a "nice pic" and discussing astrophotos. Was wondering if a photo of a double crescent moon had somehow been posted and I missed it. Or did this posting get on this thread by mistake?

3. NOW - BACK to the thread on the DOUBLE crescent moon which was started a few years back and is STILL getting relevant entries regarding others who have seen double moons. (and I do not mean from astigmatism, trick photography, or even because two folks who have dropped drawers and turned their backs on me - as a statement of frustration at my lack of sophistication with using this system!)

HERE is why I added to this thread - and why I think it would be useful to have people continue to add to this thread even though it is "old"... IF they end up at this thread as a result of a generic search for others who have seen DOUBLE crescent moons, it means we can get a number of instances documented for data purposes.

I am a biophysicist and my husband is head of the physics department at his college; becasue of this we are prone to try to gather data on odd physical situations. We were together when we both saw the double crescent in August that led me to this thread and therefor its parent site. I really want to see if we can figure out that is going on with these rare but clearly repeated and real observations.

I believe that one way to analyze what might be happening is to gather info on the date, time and location of sightings, and then go back and check out specific conditions in the area where the double moon was seen.

We are not seeking at this point to be educated as much as to find a place where data can be sought and gathered BECAUSE IT IS SOMEWHERE that generic search engines list when people who are seeking information. It is where I got sent by a search engine, it seems it is where the recent poster got to since this is where they posted.

IF CONTINUING TO ADD TO THIS THREAD AND GET NOTIFIED WHEN IT IS ADDED TO is NOT a good way to "catch" people seeking info on double moons, what is a better way to do it? Any ideas??

Sincerely -

eburacum45
2007-Dec-10, 06:05 AM
Les Cowley might be a good person to ask about this phenomenon:
http://www.atoptics.co.uk/
his website has details of many different mirages and ice crystal effects. I don't know if double moons are caused by a mirage effect or an ice-crystal reflection effect (or something else) but it may be that Les might have some ideas.

OTP1
2007-Dec-17, 06:37 PM
http://img.photobucket.com/albums/v432/dbsnooper/notmine.jpg

Jerry
2007-Dec-18, 04:55 AM
I saw a double moon stumbling home the other night, too:)

I wouldn't consider a double moon a mirage - both images are real, as always slightly displaced by diffaction in the atmosphere.

What it takes is a sudden change in atmospheric density - usually an inversion, where heavy cold air is trapped below a much warmer, lighter layer. You see the moon differentially refracted-the path through the air is slightly longer in one image than the other.

Neverfly
2007-Dec-19, 07:07 AM
Bold Mine:


of course, the first thing I did was point it out to a neighbor, just to make sure I wasn't seeing things. she and her kids confirmed that, yes, there it was, and no, I wasn't blind or crazy. (mentally ill is a different discussion.)

so what causes this? it's clear out tonight--very clear and a bit chilly. I'm in Olympia, WA, in a part of town that's pretty suburban--but since I've never seen it before, I don't think it's an effect from the street lights. is it?

I could not help but notice that the letter s at the start of your sentence was not capitalized. I find your lack of grammar infuriating. It's driving me crazy...




Ohhhhhh... You KNOW I couldn't resist!!:p


ETA: Just trying to help the ignorant English major out... :whistle:

GinaLynn
2008-Feb-05, 12:13 AM
Hi. This isn't about a double crescent moon, and I apologize for that. However, I thought that you guys might find this interesting.

I was on picket duty in late October, 1995, when I saw something I will never forget. Around 10:00 a.m. I happened to look straight up in the sky and saw the moon. It appeared very large and was about 1/2 full (sorry, I don't know the proper term). After staring at it for a couple of minutes, it occurred to me that it was in the wrong part of the sky. That's when I looked southward, towards the horizon and saw it again. I did a double-, triple-, quadruple-take! I couldn't believe my eyes. I did a comparison and the moons were identical.

I was alone that day. picketing a less-used back entrance to Fred Meyer main office, in Portland, OR. I couldn't believe my luck - that day there was noone there to back me up as to what I was seeing! I even tried to stop a couple of bicyclists to get them to stop and look up to see what I was seeing. I guess they figured I was crazy since they wouldn't stop for me.

I continued to look back and forth, at the moon in the sky above and the one at the horizon. Until it made me dizzy. I kept expecting the one overhead to disappear. After awhile, I guess I got tired of looking at them, especially with noone to discuss them with. My attention wandered and before I knew it, it was afternoon and my husband was picking me up. I looked for the moons, but, of course, they were gone. He didn't believe that I had really seen what I had seen.

So that was that. Every so often, I Google the internet looking for any mention of two moons being sighted in the sky at once. This is the first one that I have found. My sighting was in the daytime, a lot different than the ones seen at night. They were much closer together and a lot easier to explain, it seems.

I wonder if it a coincidence that the double crescent moon was sighted in the Pacific Northwest too? (No, I wasn't drinking and I'm not crazy!)

Let me know what you think of my experience, okay?

Neverfly
2008-Feb-05, 12:31 AM
Hi. This isn't about a double crescent moon, and I apologize for that. However, I thought that you guys might find this interesting.

I was on picket duty in late October, 1995, when I saw something I will never forget. Around 10:00 a.m. I happened to look straight up in the sky and saw the moon. It appeared very large and was about 3/4 full (sorry, I don't know the proper term). After staring at it for a couple of minutes, it occurred to me that it was in the wrong part of the sky. That's when I looked southward, towards the horizon and saw it again. I did a double-, triple-, quadruple-take! I couldn't believe my eyes. I did a comparison and the moons were identical.

I was alone that day. picketing a less-used back entrance to Fred Meyer main office, in Portland, OR. I couldn't believe my luck - that day there was noone there to back me up as to what I was seeing! I even tried to stop a couple of bicyclists to get them to stop and look up to see what I was seeing. I guess they figured I was crazy since they wouldn't stop for me.

I continued to look back and forth, at the moon in the sky above and the one at the horizon. Until it made me dizzy. I kept expecting the one overhead to disappear. After awhile, I guess I got tired of looking at them, especially with noone to discuss them with. My attention wandered and before I knew it, it was afternoon and my husband was picking me up. I looked for the moons, but, of course, they were gone. He didn't believe that I had really seen what I had seen.

So that was that. Every so often, I Google the internet looking for any mention of two moons being sighted in the sky at once. This is the first one that I have found. My sighting was in the daytime, a lot different than the ones seen at night. They were much closer together and a lot easier to explain, it seems.

I wonder if it a coincidence that the double crescent moon was sighted in the Pacific Northwest too? (No, I wasn't drinking and I'm not crazy!)

Let me know what you think of my experience, okay?

There was another thread here that discussed similar, in which a ring of suns is observed under the right atmospheric conditons. I cannot think of any reason why the moon can't be seen that way too.

I can't remember the thread offhand... But I'll look around a bit.
ETA: If I remember right, it was four suns, like in a ring. Balanced distance between each.

ETA Again:This link from NASA talks about atmospheric conditions that can make some crazy things appear in the sky:
http://science.nasa.gov/headlines/y2002/24oct_sunrings.htm
Here is a YouTube clip of the Sundogs I was talking about. Is there such a thing as Moondogs? Maybe Moonpuppies...:whistle:
http://www.youtube.com/watch?v=qrh_fxKwBlM

Neverfly
2008-Feb-05, 12:48 AM
I cannot find the BAUT thread on it. Maybe someone who is better at searching the forums than I am will at some point.

Hopefully the NASA link in the ABOVE Edit To Add will hope you a little bit.

But sometimes, the ice in the upper atmosphere can give a mirror effect.

So, no- you're not crazy. Even 13 years later.;)

Buzz-Lite-Punch
2008-Feb-05, 02:30 AM
Hello there, being doing astronomy, real bad for the past 29 years, wow 29 years. I noticed something back around summertime last year, a shadow on Venus though the telescope, and since reading this thread I was wondering if this is connected with the temperature differences that created the double crescent moon?:confused:

Neverfly
2008-Feb-05, 02:42 AM
Hello there, being doing astronomy, real bad for the past 29 years, wow 29 years. I noticed something back around summertime last year, a shadow on Venus though the telescope, and since reading this thread I was wondering if this is connected with the temperature differences that created the double crescent moon?:confused:

What do you mean by a shadow on Venus? Venus goes through Phases...

Disinfo Agent
2008-Feb-06, 08:07 PM
The picture in OTP1's post is more or less how I usually see the Moon. Until now, I thought that was because of poor eyesight (I wear glasses)!

Jerry
2008-Feb-07, 03:16 AM
Hi. This isn't about a double crescent moon, and I apologize for that. However, I thought that you guys might find this interesting.

I was on picket duty in late October, 1995, when I saw something I will never forget. Around 10:00 a.m. I happened to look straight up in the sky and saw the moon. It appeared very large and was about 3/4 full (sorry, I don't know the proper term). After staring at it for a couple of minutes, it occurred to me that it was in the wrong part of the sky. That's when I looked southward, towards the horizon and saw it again. I did a double-, triple-, quadruple-take! I couldn't believe my eyes. I did a comparison and the moons were identical.

I continued to look back and forth, at the moon in the sky above and the one at the horizon. Until it made me dizzy. I kept expecting the one overhead to disappear. After awhile, I guess I got tired of looking at them, especially with noone to discuss them with. My attention wandered and before I knew it, it was afternoon and my husband was picking me up. I looked for the moons, but, of course, they were gone. He didn't believe that I had really seen what I had seen.

So that was that. Every so often, I Google the internet looking for any mention of two moons being sighted in the sky at once. This is the first one that I have found. My sighting was in the daytime, a lot different than the ones seen at night. They were much closer together and a lot easier to explain, it seems.
?
First, I believe you. Second, I think there is a rational explanation. I live in a place where there is often inversion, and I often see things from the base of a very sharply defined cloud floor. It is not unusual, given a highly reflective lake, a bright sun and a dark cloud floor to see shadows in the cloud floor that are virtual anti-reflections of objects near the sun.

Although it would be rare, it would certainly not be impossible to catch a cloud at an angle that reflected the moon. One is much more likely to see such a reflection in a plate glass window, but it might happen.

OTP1
2008-Feb-15, 12:59 AM
Actually, Seeing the moon in exactly the same position, in the opposite side of the sky, happens from time to time. It's caused by very high altitude ice crystals that reflect the light, and in the right conditions, becomes a mirror of sorts.

Here is an example of Sun dogs caused by the same thing.

Sun dogs (http://www.youtube.com/watch?v=qrh_fxKwBlM&feature=related)

I guess these Lunar apparitions are called Moon dogs.

Neverfly
2008-Feb-15, 05:54 AM
Actually, Seeing the moon in exactly the same position, in the opposite side of the sky, happens from time to time. It's caused by very high altitude ice crystals that reflect the light, and in the right conditions, becomes a mirror of sorts.

Here is an example of Sun dogs caused by the same thing.

Sun dogs (http://www.youtube.com/watch?v=qrh_fxKwBlM&feature=related)

I guess these Lunar apparitions are called Moon dogs.

I got first dibs:lol:
And Welcome to BAUT OTP1.

hhEb09'1
2008-Feb-17, 01:43 PM
I was on picket duty in late October, 1995, when I saw something I will never forget. Around 10:00 a.m. I happened to look straight up in the sky and saw the moon. It appeared very large and was about 3/4 full (sorry, I don't know the proper term). After staring at it for a couple of minutes, it occurred to me that it was in the wrong part of the sky. That's when I looked southward, towards the horizon and saw it again. I did a double-, triple-, quadruple-take! I couldn't believe my eyes. I did a comparison and the moons were identical.

I was alone that day. picketing a less-used back entrance to Fred Meyer main office, in Portland, OR.
Let me know what you think of my experience, okay?Ah, a detective story! Thanks, GinaLynn, and welcome to BAUT!

First, there's a problem of the timeline. Apparently, there was a new moon on October 24, 1995, so that there could not have been a three-quarter moon in late October of that year.

Second, if a moon is visible in Portland OR at 10am, during the daytime, it has to be less than half full, since it would be close to the sun.

I'm still not sure what you saw, though! :)

GinaLynn
2008-Feb-17, 08:58 PM
hhEb09'1,

Thanks for the info on the timeline! It very likely could have been a half moon versus a three-quarter moon. The sighting was, after all, twelve years ago!!! I wrote down all the details after I got home from picketing that day. (The exact date and time, and a description of what I actually saw.) And I probably still have the notes somewhere, burried under 12 years of accumulated "stuff".

And to clarify (or muddy) things further, the sighting might have happened closer to 9:30 or 10:30 a.m., than 10:00 a.m. It's also possible that it happened closer to the middle of October, than the later part.

Thank you, Neverfly, for nudging me about the reply to my posting! -Gina Lynn




Ah, a detective story! Thanks, GinaLynn, and welcome to BAUT!

First, there's a problem of the timeline. Apparently, there was a new moon on October 24, 1995, so that there could not have been a three-quarter moon in late October of that year.

Second, if a moon is visible in Portland OR at 10am, during the daytime, it has to be less than half full, since it would be close to the sun.

I'm still not sure what you saw, though! :)

hhEb09'1
2008-Feb-17, 09:25 PM
Thanks for the info on the timeline! It very likely could have been a half moon versus a three-quarter moon. The sighting was, after all, twelve years ago!!! I wrote down all the details after I got home from picketing that day. (The exact date and time, and a description of what I actually saw.) And I probably still have the notes somewhere, burried under 12 years of accumulated "stuff".

And to clarify (or muddy) things further, the sighting might have happened closer to 9:30 or 10:30 a.m., than 10:00 a.m. It's also possible that it happened closer to the middle of October, than the later part.Keep us posted! We seldom get such fine details. :)

The moon could have been more full, the closer it was to setting--but if it were close to setting, you wouldn't see it overhead. 'Course, the overhead one might've been the reflection.

I'll wait for your notes, before I speculate further.