Mars and Orion Over Monument Valley (APOD 25 Dec 2007)

Comments and questions about the APOD on the main view screen.
Post Reply
CuDubh
Ensign
Posts: 15
Joined: Tue Dec 25, 2007 7:41 am

Mars and Orion Over Monument Valley (APOD 25 Dec 2007)

Post by CuDubh » Tue Dec 25, 2007 7:58 am

There are no volcanic rocks in this picture!!!

These buttes are composed of sandstone and mudstone.

They are erosional remnants--quite unusual to be sure, but obviously stratigraphically continuous with the adjacent mesa.

Another minor peeve: either this picture is quite cleverly done with high speed film on a dark night, or it is faked. Could we have details?

geonuc
Ensign
Posts: 22
Joined: Thu Dec 20, 2007 1:10 pm
Location: Atlanta, USA

Re: Mars and Orion Over Monument Valley

Post by geonuc » Tue Dec 25, 2007 11:36 am

CuDubh wrote:There are no volcanic rocks in this picture!!!
...
Very true. Perhaps the photographer thought these buttes were of similar origin to Shiprock, which is volcanic.

User avatar
Case
Commander
Posts: 617
Joined: Sat Jun 09, 2007 10:08 pm
Location: (52°N, 06°E)

Re: Mars and Orion Over Monument Valley

Post by Case » Tue Dec 25, 2007 1:50 pm

CuDubh wrote:Another minor peeve: either this picture is quite cleverly done with high speed film on a dark night, or it is faked. Could we have details?
MV appears to have a FOV of ~70° wide (could be 60), watching east (Google Earth). The night sky in the image appears ~60° wide. By the position of Mars in Gemini, it seems the picture was taken around 11 Dec 2007, when Mars and Orion were just coming up in the east, just after dark. Seems like a good fit. The stars in the image have a slight trail, suggesting the sky was photographed for a short time from a not-rotating mount.
I do not think this is a montage like some other landscapes with the Milky Way, which require much longer exposures.

marion ballantyne
Ensign
Posts: 12
Joined: Tue Oct 16, 2007 10:20 am

apod 25/12/07

Post by marion ballantyne » Tue Dec 25, 2007 2:18 pm

Does it matter whether the rocks are igneous or sedimentary? The APOD is breathtaking, especially with Mars shining so brightly in a non-light-polluted sky.
Marion

growlands
Asternaut
Posts: 2
Joined: Tue Dec 25, 2007 5:31 pm

Post by growlands » Tue Dec 25, 2007 5:42 pm

Does it matter whether the rocks are igneous or sedimentary? The APOD is breathtaking, especially with Mars shining so brightly in a non-light-polluted sky.
For people like me who come to this site to find great photography and good science, yes, it does matter.

craterchains
Commander
Posts: 807
Joined: Thu Jul 21, 2005 2:57 pm
Location: On a boat near Tacoma, WA, usa
Contact:

Post by craterchains » Tue Dec 25, 2007 7:17 pm

This site should all ways and always show good science.

Hope all that celebrate these hollidays have safe and great times.

Merry X - Mass
and a Happy New year to all.

Norval
"It's not what you know, or don't know, but what you know that isn't so that will hurt you." Will Rodgers 1938

iampete
Ensign
Posts: 59
Joined: Mon Nov 19, 2007 5:36 am
Location: Southern California, USA

Post by iampete » Tue Dec 25, 2007 9:20 pm

I find the inclusion of pics such as this on APOD problematic.

One of the pleasures of APOD is that most of the pics are at least "quasi-" public domain, i.e., I can download them, send them to friends, etc., so long as I don't seek to profit from them or claim them as my own. (not a lawyer, so this is just a layman's perspective - and, yes, I'm aware of the APOD image permissions policy)

The TWAN website explicitly prohibits "downloading for any purpose" (emphasis mine), etc., etc. The inclusion of pics such as this on the APOD site, in my opinion, crosses (or at least closely approaches) the line of government (nasa.gov) hucksterism for some non-public entity (although self-described as one with possibly admirable goals) that, according to their own site, is a "not for profit corporation" which is seeking to raise money by various means.

This differs from most other non-gov't pics on APOD, as the providers of those pix don't appear to be in the business of raising money, or at least not quite so obviously.

The fact that a co-director of APOD is on the "TWAN team", just reeks of conflict of interest.

Just my 2 cents.

scrufty
Asternaut
Posts: 1
Joined: Wed Dec 26, 2007 4:29 am

Post by scrufty » Wed Dec 26, 2007 4:42 am

I don't know much about astronomy. I heard mars was close. checked it out in the sky tonight, then went to this site. the picture was awesome. bummer if it is a fake. How long will we be able to see mars?

User avatar
BMAONE23
Commentator Model 1.23
Posts: 4076
Joined: Wed Feb 23, 2005 6:55 pm
Location: California

Post by BMAONE23 » Wed Dec 26, 2007 6:09 am

You will never see Mars at the same apparent size of the Moon without the aid of a telescope. The posted image is, relatively speaking, as large as Mars will ever appear when viewed, unaided, from the Earth. The Internet postings that state Mars will appear to be the same size as the Moon are Hoaxes. This Posted Image from this post is the truth. Image

Mars will remain visible for some (7 or so) months before it travels around the sun and out of view.

User avatar
Qev
Ontological Cartographer
Posts: 576
Joined: Wed Mar 08, 2006 8:20 pm

Re: Mars and Orion Over Monument Valley

Post by Qev » Wed Dec 26, 2007 7:07 am

CuDubh wrote:There are no volcanic rocks in this picture!!!

These buttes are composed of sandstone and mudstone.
Buttes are often capped with harder rock of volcanic origin, which is why they erode the way they do.
Don't just stand there, get that other dog!

kovil
Science Officer
Posts: 351
Joined: Thu Jan 26, 2006 1:58 pm

Post by kovil » Wed Dec 26, 2007 7:15 am

Thanks APOD for a beautiful Christmas computer screen background !!!
I've been enjoying it all day !

So where did all the cubic miles of dirt that was supposedly eroded go?
And when?

geonuc
Ensign
Posts: 22
Joined: Thu Dec 20, 2007 1:10 pm
Location: Atlanta, USA

Re: Mars and Orion Over Monument Valley

Post by geonuc » Wed Dec 26, 2007 12:18 pm

Qev wrote:
CuDubh wrote:There are no volcanic rocks in this picture!!!

These buttes are composed of sandstone and mudstone.
Buttes are often capped with harder rock of volcanic origin, which is why they erode the way they do.
While that is true in other regions, it is not the case in Monument Valley. The capstone rock is a relatively impermeable member of the Chinle Formation, I believe.

The features we see in Monument Valley - like those of the surrounding national parks - are relatively new, geologically speaking. The local uplift is part of the the Laramide orogeny, which began about 60 million years ago. However, the major erosional events are still younger - maybe 2 million years old.

The sediments from this process are generally washed out to sea by rivers. With other uplift features, such as the basin & range (think Death Valley), the erosional sediments fill up the valleys between the ranges, as well as being washed to sea.

marion ballantyne
Ensign
Posts: 12
Joined: Tue Oct 16, 2007 10:20 am

mars and orion over monument valley

Post by marion ballantyne » Wed Dec 26, 2007 12:41 pm

The rocks are eroded over millions of years by weathering. Rain and wind are the principal eroding factors. They finally end up in the seas and oceans creating sedimentary formations of the future. In the case of Monument Valley where temperature ranges are high the rate of erosion would be greater, therefore erosion would be faster than say in a temperate climate.
Marion

User avatar
NoelC
Creepy Spock
Posts: 876
Joined: Sun Nov 20, 2005 2:30 am
Location: South Florida, USA; I just work in (cyber)space
Contact:

I object to the word "fake"

Post by NoelC » Wed Dec 26, 2007 2:16 pm

I'm not saying this was done in this case, but...

If a person were to stand a camera on a tripod and take a long exposure of the landscape. Then they put the camera on a tracking mount and took a long exposure (or multiple long exposures for stacking) and captured the stars and planets to great depth, then combined the images digitally to represent what one would see if one had a camera (or eyes) of incredible sensitivity, how exactly is this a fake?

It is not a fake any more or less than a "photograph" is a "fake" representation of the reality it captures.

-Noel

ETX_90
Ensign
Posts: 42
Joined: Sat Jan 01, 2005 7:01 pm
Location: Dallas, TX

Post by ETX_90 » Thu Dec 27, 2007 7:38 pm

I've been to Monument Valley, and its limiting magnitude at night is one of the highest in the country (6.7), so I can imagine how even a slightly long exposure could produce a very bright image like the one being discussed.
Gnidakcolhcs

User avatar
iamlucky13
Commander
Posts: 515
Joined: Thu May 25, 2006 7:28 pm
Location: Seattle, WA

Re: Mars and Orion Over Monument Valley

Post by iamlucky13 » Thu Dec 27, 2007 9:06 pm

CuDubh wrote:Another minor peeve: either this picture is quite cleverly done with high speed film on a dark night, or it is faked. Could we have details?
I'm curious why you think it might be a fake? Pictures like this are not at all uncommon in astrophotography.
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

CuDubh
Ensign
Posts: 15
Joined: Tue Dec 25, 2007 7:41 am

Re: I object to the word "fake"

Post by CuDubh » Fri Dec 28, 2007 6:43 am

Yeah, fake was not a good choice of word. I was merely curious whether the image was obtained as you describe (a composite), or whether it is possible to achieve this with a single exposure (short, to avoid streaking of the stars or foreground). In either case it is very well done.
NoelC wrote:I'm not saying this was done in this case, but...

If a person were to stand a camera on a tripod and take a long exposure of the landscape. Then they put the camera on a tracking mount and took a long exposure (or multiple long exposures for stacking) and captured the stars and planets to great depth, then combined the images digitally to represent what one would see if one had a camera (or eyes) of incredible sensitivity, how exactly is this a fake?

It is not a fake any more or less than a "photograph" is a "fake" representation of the reality it captures.

-Noel

Post Reply