Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_inspirational_skies.thumb.jpg.a20cdbfeadc049807f6d78e6c00ee900.jpg

jackamus

Sun and Moon anomaly

Recommended Posts

I have been trying to get to the bottom of this anomaly and most of the solutions suggest its an illusion. This is based on the fact that I was using a photograph and that various factors need to be taken into account e.g. lens distortion, cylindrical projection etc. I ony used the photo to visually convey what I had observed.
I could easily have drawn on a blackboard what I observed and taken a photo of it thus doing away with optical distortions/illusions etc.
I take the view that the sun and the moon are just two large balls in 3 dimensional space and I created the drawing shown below the photo. The drawing is virtually the same model only using a torch and a ball.
Both models demonstrate that a straight perpendicular line between both objects can be drawn except you cannot do this, using the observed (not photographic) positions, of the sun and the Moon. Why is this?

Sun Moon 2 .jpg

Share this post


Link to post
Share on other sites

No idea really, maybe something to do with the Sun being around 93 million miles away and the  Moon only average 240 thousand miles away.

Dave

Share this post


Link to post
Share on other sites

Thats a very wide angle photo, the geometry of which is not shown in the diagram.  Look at the power lines in your photo.  That may give a clue maybe.

Share this post


Link to post
Share on other sites
16 minutes ago, Davey-T said:

No idea really, maybe something to do with the Sun being around 93 million miles away and the  Moon only average 240 thousand miles away.

Dave

Not really distance or size doesn't matter! How can it make any difference? The obvious rational explanation is the sun doesn't illuminate the moon. I realize this may be considered heresy but I'm more interested in the truth and not belief.

Share this post


Link to post
Share on other sites
Posted (edited)
10 minutes ago, Owmuchonomy said:

Thats a very wide angle photo, the geometry of which is not shown in the diagram.  Look at the power lines in your photo.  That may give a clue maybe.

I did acknowledge that photos can be misleading and that is why I said I could have drawn it on a blackboard and taken a photo of that. I observe a moon being illuminated from above at about an angle of 45deg but the sun slightly below the moon. The problem still hasn't been explained. The problem is worse earlier in the morning because the sun was even lower in the sky but the moon was still in the some position!

Edited by jackamus
Additionasl thought.

Share this post


Link to post
Share on other sites

How was the image taken?  Was it a stitched panoramic shot?

Share this post


Link to post
Share on other sites

I think real world phenomena are often not too obvious on blackboard scale.
But I have always been convinced by science... Practical "Infinities" (distance)
explain many apparent anomalies... with a bit (or quite a lot!) of thought? 🙂

Was amply taken in by this picture (recently) re-Tweeted on the interweb. 😛

Mars..jpg.7b97638ba931c71061202e3fcec92390.jpg

Share this post


Link to post
Share on other sites
Posted (edited)

Hi ... had same reflexions since years and eventually found myself the explanation last year.

Since we see the moon's lighted shape independently of its rotation on itself, and independently of earth rotation (i.e. day hour), this shape indicates the real position of the sun in space, which, given the sun distance, happens to be almost the same direction as earth - sun.

Given that, we see the moon's lighted face inclined because earth is round and our ground is inclined over ecliptic and sun direction. The exact angle should not be your latitude (because earth equator / rotation axis are inclined too) but rather your sun's maximum height for your place, when sun crosses the meridian. So the moon's face inclination is bigger in summer and lower in winter...

It seems mankind always had proof of earth being round under the eyes, without having to travel round the globe 😉

PS: I hope it's clear enough... I don't need a drawing myself, but I could make one if needed.

Edited by rotatux

Share this post


Link to post
Share on other sites

What you are saying would be true if we were on the equator and the sun and moon followed a path directly overhead. However, at our northern latitude the plane of the ecliptic appears curved to us. This is why the moon appears on its back when rising and on its front when setting.

In your image, the moon is on its back and what you can't see, is the sun is on its front. If you observed the same from the southern hemisphere the opposite would be true.

  • Like 2

Share this post


Link to post
Share on other sites
3 hours ago, jackamus said:

Not really distance or size doesn't matter! How can it make any difference? The obvious rational explanation is the sun doesn't illuminate the moon. I realize this may be considered heresy but I'm more interested in the truth and not belief.

I'd be interested to hear what you do think illuminates the moon if you don't think its the Sun.

Share this post


Link to post
Share on other sites
1 hour ago, Spikey said:

I'd be interested to hear what you do think illuminates the moon if you don't think its the Sun.

That's for another time.

I keep saying please forget the photo for the reason we all understand. The problem is simple and it is clearly visible and can be drawn as I have shown. As 'Star forming' said I too can also draw this in a more detailed and accurate way which would wrap it up.  In fact I think I will do that and attach to my next posting.

Interestingly nobody has commented on the fact that a straight perpendicular line can be drawn from a torch illuminating a football but cannot be done for the sum illuminating the moon. I see no mechanical difference. My next drawing will explain.

Share this post


Link to post
Share on other sites
Posted (edited)

The straightest line "actually great circle on the celestial sphere" is not the one you are imagining along the horizon. In your 2-D photo the actual shortest angular distance along the celestial sphere might "appear" to be a curved line peaking near the center of the photo. When viewing live in 3-D, the direct line connecting the Sun and Moon is more obviously one that peaks around their mid-point. Indeed, it presents an optical illusion for those who expect the line representing the shortest angular distance between the Sun and Moon on the celestial sphere to loop around the horizon.

Edited by CentaurZ

Share this post


Link to post
Share on other sites
Posted (edited)

Your diagram is not correct. You have the ball and the two lights in the same plane (in the room). This is not the case. Try drawing a plan view with the sun much further away than the moon. Then imaging tilting slightly it so you are looking from the perspective in the photo then the geometry will be correct and I hope you will see the moon is correctly illuminated by the sun as seen from the earth.

Regards Andrew

Edited by andrew s
  • Like 2

Share this post


Link to post
Share on other sites
5 hours ago, jackamus said:

The obvious rational explanation is the sun doesn't illuminate the moon.

Completely the opposite of known fact.

I think enough explanation has been given as to the observed effect.

  • Like 4

Share this post


Link to post
Share on other sites

To be honest it's pretty hard to get your head around as it logically makes no sense. However once you appreciate the relationship between the two orbits/ ecliptics and both the Earth's and the Moon's tilts it makes sense if you want it to.

lossy-page1-1280px-Lunar_Orbit_and_Orientation_with_respect_to_the_Ecliptic_tif.thumb.jpg.cdfedd75ad7643e2a52df970590d2f57.jpg

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.

  • Recently Browsing   0 members

    No registered users viewing this page.

×

Important Information

By using this site, you agree to our Terms of Use.