hunchbacked's "weird" viewpoint from A17

[bknight]

hunchbacked has put a video out and I'm having trouble visualizing it. 

He is stating among other BS that the Earth is too low on the horizon in AS17-137-20957.  Now I know that as the Moon rotates the Sun will get higher in the sky, but since the Moon is tidally locked to the Earth, will the position move relative to the horizon?.
I'm having difficulty with this one too much 3_D movement.  I realize that the position above the horizon will be affected by the terrain.

[onebigmonkey]

Well for a start he's getting the location of the Earth in the sky wrong by not allowing for the tilt in the photo he uses - it is much more central to the south massif than to the left. Using Stellarium we can also work out that the angle between them is not 120 degrees but 145.

The Earth is also at at 45 degrees above horizon compared with 16 degrees for the sun.

By the end of the mission the sun had risen to over 40 degrees above the horizon but the angular separation between it and Earth was still 133 degrees.

Additionally, he states that AS17-134-20411 was taken not long before AS17-137-20957, but in reality they were taken over 20 hours apart on different EVAs, so his shadow calculations get even more wrong.

He also states that the photo in question is usually explained (by normal people) by it being taken up a slope, but fails to mention that the slope actually amounts to well over 2000 metres of elevation.

So really, he gets all his maths wrong by getting the position of the Earth wrong, and gets all confused by a big lump of hill taking up most of a frame instead of sky.

Here's where Earth is above the South Massif captured in two astronaut visors



and in a compilation of screenshots from the rover TV



e2a: The broadcast from which the above image was taken was also done at station 2, the location of hunchback's photo, and you not only get a view of Earth in it but you get a zoomed close-up that matches the Earth in the still photo (not sure if you can see them taking the image in this clip).

[bknight]

OK, so the Earth stays relatively fixed above the horizon given similar terrains?

[bknight]

Well for a start he's getting the location of the Earth in the sky wrong by not allowing for the tilt in the photo he uses - it is much more central to the south massif than to the left. Using Stellarium we can also work out that the angle between them is not 120 degrees but 145.

The Earth is also at at 45 degrees above horizon compared with 16 degrees for the sun.

By the end of the mission the sun had risen to over 40 degrees above the horizon but the angular separation between it and Earth was still 133 degrees.

Additionally, he states that AS17-134-20411 was taken not long before AS17-137-20957, but in reality they were taken over 20 hours apart on different EVAs, so his shadow calculations get even more wrong.

I gathered that and did not agree with his shadow.  Additionally the relief would have to be flat to have the correct shadow "direction".

He also states that the photo in question is usually explained (by normal people) by it being taken up a slope, but fails to mention that the slope actually amounts to well over 2000 metres of elevation.

Sneaky isn't he, there was another poster who pointed that out to him.

So really, he gets all his maths wrong by getting the position of the Earth wrong, and gets all confused by a big lump of hill taking up most of a frame instead of sky.

Here's where Earth is above the South Massif captured in two astronaut visors



and in a compilation of screenshots from the rover TV



e2a: The broadcast from which the above image was taken was also done at station 2, the location of hunchback's photo, and you not only get a view of Earth in it but you get a zoomed close-up that matches the Earth in the still photo (not sure if you can see them taking the image in this clip).

Thanks obm.

[onebigmonkey]

This is something I put together out of curiosity because I liked the photo with the LRV in it - you can see the tracks that lead up to boulder 2, which features in several images taken at the same time as hunchback's obsession. It's a guess based on matching rocks on the horizon in two different images, but not too far out.



And just for fun, here's the Earth in the photograph and TV images compared with the weather satellite photo on the same day:



Also worth pointing out that one of his shadow angle calculations is assuming where the sun would be at the end of the mission. The two photos he picks were done in EVAs 1 and 2, so where the sun is on EVA-3 has got nothing to do with anything!

[bknight]

OK, so the Earth stays relatively fixed above the horizon given similar terrains?  Approximately 45 degrees at this mission?

[onebigmonkey]

OK, so the Earth stays relatively fixed above the horizon given similar terrains?  Approximately 45 degrees at this mission?

More or less, depending on libration (which hunchbacked does acknowledge).

[bknight]

OK, so the Earth stays relatively fixed above the horizon given similar terrains?  Approximately 45 degrees at this mission?

More or less, depending on libration (which hunchbacked does acknowledge).

That was specifically what my mind had trouble grasping in the 3D real world.  Too much moving geometry for me to resolve.
Thanks again obm