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roidspop
2002-Mar-25, 04:41 AM
Among the stories about instant granite, hollow earths and glass tubes on Mars, my crankish informant has told me that Hubble has taken photographs of the lunar surface. Apparently, early in the Hubble program, NASA stated that the instrument would not be turned on the moon because its sensors could not tolerate the glare. So, with this photograph, we have a new wave of conspiracy theories based on the notion that the public has been denied high-resolution Hubble images to protect us from the knowledge that there are alien artifacts on the moon, and that this alleged photo was a slip-up.

Does anyone have anything to offer concerning this development?

Magnificent Desolation
2002-Mar-25, 06:20 AM
On 2002-03-24 23:41, roidspop wrote:
Among the stories about instant granite, hollow earths and glass tubes on Mars, my crankish informant has told me that Hubble has taken photographs of the lunar surface. Apparently, early in the Hubble program, NASA stated that the instrument would not be turned on the moon because its sensors could not tolerate the glare. So, with this photograph, we have a new wave of conspiracy theories based on the notion that the public has been denied high-resolution Hubble images to protect us from the knowledge that there are alien artifacts on the moon, and that this alleged photo was a slip-up.

Does anyone have anything to offer concerning this development?


Dear "roidspop" !

In 1999, Hubble pictures of the lunar surface was released to the general public.

There is nothing secret or "slip-up" about these pictures. You and everybody else can view them at:

http://oposite.stsci.edu/pubinfo/pr/1999/14/index.html

and

http://oposite.stsci.edu/pubinfo/pr/1999/14/extra-photos.html

"Magnificent Desolation"



<font size=-1>[ This Message was edited by: Magnificent Desolation on 2002-03-25 01:27 ]</font>

ToSeek
2002-Mar-25, 01:46 PM
However, there are statements on NASA websites indicating that Hubble can't photograph the Moon. Contradictions like this are enough to convince conspiracy theorists of an entire web of intrigue.

NASA science (http://science.nasa.gov/newhome/headlines/ast26feb99_1.htm)

Hubble FAQ (http://hubble.nasa.gov/faq.html)



_________________
"... to strive, to seek, to find, and not to yield." - Tennyson, Ulysses

<font size=-1>[ This Message was edited by: ToSeek on 2002-03-25 08:47 ]</font>

Tomblvd
2002-Mar-25, 03:21 PM
On 2002-03-25 08:46, ToSeek wrote:
However, there are statements on NASA websites indicating that Hubble can't photograph the Moon. Contradictions like this are enough to convince conspiracy theorists of an entire web of intrigue.

The only thing on the Hubble FAQ page that mentions this is this statement:



3. Too much light: This one you can probably work around, but the Moon when illuminated by the Sun is far too bright for any HST instrument to take a picture of -- the detectors would saturate in much less than the shortest exposure time. So the picture would have to be taken when the Sun wasn't illuminating the area in question -- just lit up by Earthshine.



I'm not sure how that statement translates into a statement that "Hubble can't photograph the Moon".

Obviously, there are ways to image the Lunar surface with Hubble, but since that isn't what it was built for, it is a waste of time and resources.

ToSeek
2002-Mar-25, 03:37 PM
I've been trying to figure out whether the HST photos of the Moon were taken of the lighted portion or not. That's what it looks like, but that doesn't mean a whole lot. So far I haven't found anything that tells me when the photos were taken.

DaveC
2002-Mar-25, 05:40 PM
Quote:
___________________________________________
"I've been trying to figure out whether the HST photos of the Moon were taken of the lighted portion or not. That's what it looks like, but that doesn't mean a whole lot. So far I haven't found anything that tells me when the photos were taken."
___________________________________________

Well, let's see. If Hubble can't take pictures of the solar-lit surface of the moon, it seems pretty clear when they were taken - when the subject area was in darkness. If the Copernicus picture was truly taken on April 16, 1999 as indicated, it was a new moon - consistent with the non-sunlit restriction. The dark side of the moon would benefit from full earthshine on that date which would account for the images being as bright as they are.

<font size=-1>[ This Message was edited by: DaveC on 2002-03-25 12:51 ]</font>

ToSeek
2002-Mar-25, 06:10 PM
On 2002-03-25 12:40, DaveC wrote:
If the Copernicus picture was truly taken on April 16, 1999 as indicated, it was a new moon - consistent with the non-sunlit restriction.

April 16 was the date of the press release, not of the photos (there are news reports (http://www.astronomynow.com/breaking/990417hubble/) on the subject dated April 17). I haven't yet found an indication of when the photos were taken.

ToSeek
2002-Mar-25, 06:19 PM
The image was taken while the Space Telescope Imaging Spectrograph (STIS) was aimed at a different part of the moon to measure the colors of sunlight reflected off the Moon. Hubble cannot look at the Sun directly and so must use reflected light to make measurements of the Sun's spectrum. Once calibrated by measuring the Sun's spectrum, the STIS can be used to study how the planets both absorb and reflect sunlight.


It obviously can't have been a new moon, in any case, since the whole point of the exercise was to examine the reflected sunlight. The Enterprise Mission claims that the photo was taken at lunar noon, (http://www.enterprisemission.com/hubble.htm) but they (characteristically) don't support that claim at all, so I'm not inclined to believe it.

(edited to clean up quote and add TEM claim)
_________________
"... to strive, to seek, to find, and not to yield." - Tennyson, Ulysses


<font size=-1>[ This Message was edited by: ToSeek on 2002-03-25 13:22 ]</font>

The Bad Astronomer
2002-Mar-25, 06:52 PM
Bear in mind that the point of taking the spectra of the Moon using STIS on Hubble was to get an analogue of the solar spectrum. In other words, as far as I can tell, they wanted to see what the Sun's spectrum looked like when reflected off a "planetary" target. So the spectra (and the images too of course) must have been done in local daytime on the Moon.

Also, HST cannot be pointed closer than 45 degrees to the Sun. This is a stringent limit, bent just once to get images of Venus when it was 44 degrees from the Sun. So the Moon must have been at least 3.5 days old or so when the images were taken.

Also, Hubble took spectra of the Moon when the Lunar Prospector crashed (to look for the signature of water). Those were taken at local daytime too, I believe (they were also of the limb of the Moon, which is much less bright than center due to the way the Moon reflects light). They were very short exposures. Note that a spectrum is less sensitive to overexposure than an image, since the light is smeared out over many pixels. What would be 1 pixel in an image is dispersed over a row of 1024 pixels. That makes the flux per pixel a lot lower.

2002-Mar-28, 11:32 AM
<a name="20020328.5:20"> page 20020328.5:20 aka 1 999
On 2002-03-25 12:40, DaveC wrote: To: 5:2
Quote:
___________________________________________
"I've been trying to figure out whether the HST photos of the Moon were taken of the lighted portion or not. That's what it looks like, but that doesn't mean a whole lot. So far I haven't found anything that tells me when the photos were taken."
___________________________________________

Well, let's see. If Hubble can't take pictures of the solar-lit surface of the moon, it seems pretty clear when they were taken - when the subject area was in darkness. If the Copernicus picture was truly taken on April 16, 1999 as indicated, it was a new moon - consistent with the non-sunlit restriction. The dark side of the moon would benefit from full earthshine on that date which would account for the images being as bright as they are.
#2Well i'll try to 1. Find the photo 2: look4 the Shadow'$
in general I think that I agree whith the basic
premis.. Earth Shine would light Moon when NEW

JayUtah
2002-Mar-28, 02:08 PM
I've seen other (non-HST) photos of the moon taken with only earthshine as the illumination. It's possible.

DaveC
2002-Mar-28, 06:17 PM
It is possible - although BA has pretty much shot down the idea that these particular Hubble images were done that way. It's not uncommon to be able to see the "dark side" of the moon if one is far away from the glare of city lights. I'd guess if you can see it, you can photograph it with sensitive film and a long exposure. Haven't tried it though.

There seems to be a lot of confusion around Hubble and the moon. It obviously CAN focus on the moon and track its relative movement long enough to make a clear picture. It CAN photograph the sunlit face of the moon. Even though lunar photos are not its raison d'etre, it CAN do a creditable job of producing them. Whether it is any better at it than some of the largest earth-based telescopes is something that I'm not clear on, but I'd guess the precise tracking of the moon is much more difficult from orbit than from the ground, making long exposures by HST more apt to be a bit blurred.

Has anyone been able to find when those Hubble images of the moon were created?

ToSeek
2002-Mar-28, 07:33 PM
On 2002-03-28 13:17, DaveC wrote:

Has anyone been able to find when those Hubble images of the moon were created?


I've given up and emailed the Office of Public Outreach at the Space Telescope Science Institute. If they give me an answer, I'll let you know.

ToSeek
2002-Apr-03, 12:44 PM
From our good friends at the Space Telescope Science Institute:



The observations of the moon were taken on November 6, 1998 between 9:21:14pm GMT and 9:49:14pm GMT.

Hope this helps.

Office of Public Outreach


The Moon was just past full at the time, which proves that NASA is totally dishonest about the capabilities of the Hubble and could easily take photographs of the crystal fortresses the aliens have built on the Moon and probably have except that they're not going to share it with the public because the Brookings Institute report (which governs everything NASA does even though it was written forty years ago and NASA never mentions it) says everyone would panic.

Donnie B.
2002-Apr-03, 12:48 PM
Er, maybe this was mentioned earlier (I didn't re-read the thread) but didn't NASA compensate for the brightness of the Moon by (a) shutting down some of the more sensitive instruments, and (b) taking a very short exposure by "ambushing" the Moon (pointing the telescope to where the Moon was about to go, then waiting for it to scoot into place)?

The Bad Astronomer
2002-Apr-03, 03:18 PM
I'm not sure about shutting down other instruments; at least STIS and WFPC2 were on (STIS was the primary instrument used to do the scientific observations, and WFPC2 made the nifty pix everyone has seen).

If I get a chance I'll see what I can dig up on this. Also, I hear there's a book that has a section in a chapter about HST that talks about this specifically... /phpBB/images/smiles/icon_wink.gif