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Forealfc
2003-Oct-20, 01:59 PM
When the US landed on moon, there is a pix showing an astronaut saluting the US Flag, would you have been able to see that from a telescope from earth? Did they leave the flag there? Do you really think we did go to the moon?

Haglund
2003-Oct-20, 02:52 PM
I don't think we have a telescope with that capacity, but yes they left the flag and other things there. And yes they did go there.

Forealfc
2003-Oct-20, 03:23 PM
Okay, you are telling me that Hubble could not spot the flag on the moon, but Hubble can spot the head of a buffalo nickel on earth. Can you explain this please.

Haglund
2003-Oct-20, 03:58 PM
The moon, and the earth, are both too bright for Hubble to observe.

Fraser
2003-Oct-20, 04:02 PM
Hubble can actually look at the Moon, and there are a few pictures available. Here's a link to Hubble's FAQ on this subject:

http://hubblesite.org/reference_desk/faq/a...d=77&cat=topten (http://hubblesite.org/reference_desk/faq/answer.php.id=77&cat=topten)

It also has a link to a picture Hubble took of the Moon.

Haglund
2003-Oct-20, 04:06 PM
Ah thanks for correcting me :) I apparently believed some sort of urban myth there.

Dave Mitsky
2003-Oct-20, 04:31 PM
Assuming an angular resolution of 0.05 arc seconds the HST is capable of a linear resolution of 93 meters or 102 yards, as derived from the small angle formula. The lower portion of the LEM is considerably smaller than that and the flag much smaller still.

A 45 meter aperture would be necessary to acheive the required resolution.

Dave Mitsky

Fraser
2003-Oct-20, 06:46 PM
Then we'll just have to build one. :-)

zephyr46
2003-Oct-21, 12:26 AM
what sort of picture of the universe would that give us?

DippyHippy
2003-Oct-21, 03:55 AM
Isn't Parker right in saying though that using the HST to observe the Earth and Moon would damage it's instruments?

Haglund
2003-Oct-21, 12:14 PM
But apparently there are images of the moon taken by Hubble...

Planetwatcher
2003-Oct-22, 04:58 PM
A 45 meter aperture would be necessary to acheive the required resolution.
Could that be accomplished by aiming three or more connected large telescopes at the same object like the way that Keck does it?

Dave Mitsky
2003-Oct-26, 03:41 AM
Originally posted by Planetwatcher@Oct 22 2003, 04:58 PM

A 45 meter aperture would be necessary to acheive the required resolution.
Could that be accomplished by aiming three or more connected large telescopes at the same object like the way that Keck does it?
Interferometers do not produce visual images as such so the answer is no.

Dave Mitsky

Dave Mitsky
2003-Oct-26, 03:48 AM
Originally posted by DippyHippy@Oct 21 2003, 03:55 AM
Isn't Parker right in saying though that using the HST to observe the Earth and Moon would damage it's instruments?
No, he isn't. However, the HST cannot be aimed at objects that are too close to the sun in angular distance.

On one occasion the HST did in fact image the Moon - see http://hubblesite.org/newscenter/archive/1999/14/

http://www.inconstantmoon.com/lim_0307.htm may prove informative.

Dave Mitsky

Matthew
2003-Oct-26, 04:06 AM
There are a couple of probes going to the moon in the next few years. Apparently one of them will check the Apollo landing sites to see if the landers and flags are still there.

kashi
2003-Oct-26, 12:12 PM
why would they not be there?

Josh
2003-Oct-26, 12:18 PM
because they never landed there in the first place! Perhaps they're going to put them there???

...please note sarcasm.

Haglund
2003-Oct-27, 11:54 AM
I think it would be very difficult to fake the lunar landings.

Matthew
2003-Oct-28, 05:32 AM
It would be extremely difficult to. There would have been hundreds of people who would have had to 'fake' the lunar landing. And thousands more had to work on (at least what they thought) the real lunar landing. You would have to keep at least hundreds of people quiet with what would be a massive secret. Or did hundreds of people die suddenly die between 1961 and 1972? And wouldn't one of the thousand people who thought they were working on the apollo program, have worked out that something was amiss?

It'd be much more difficult for a country to fake a lunar landing these days, than it would have been in 1969.

CHRIS
2003-Oct-28, 08:11 AM
Originally posted by kashi@Oct 26 2003, 12:12 PM
why would they not be there?
THE ALIENS TOOK THEM

Haglund
2003-Oct-28, 09:20 AM
Originally posted by CHRIS+Oct 28 2003, 08:11 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (CHRIS @ Oct 28 2003, 08:11 AM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-kashi@Oct 26 2003, 12:12 PM
why would they not be there?
THE ALIENS TOOK THEM [/b][/quote]
Those *******s&#33;

berserk
2003-Oct-28, 01:51 PM
Originally posted by Dave Mitsky@Oct 20 2003, 04:31 PM
Assuming an angular resolution of 0.05 arc seconds the HST is capable of a linear resolution of 93 meters or 102 yards, as derived from the small angle formula. The lower portion of the LEM is considerably smaller than that and the flag much smaller still.

A 45 meter aperture would be necessary to acheive the required resolution.

Dave Mitsky
I wonder what do your result mean: With a "45m aperture telescope", would it be viewable from HST location or from Earth&#39;s surface? Also: Do a telescope with that aperture exist? if not, which size is the biggest one?

Thanx&#33;

Dave Mitsky
2003-Oct-29, 08:23 AM
The largest full aperture optical telescopes at present are the two 10 meter Keck Telescopes at Mauna Kea. Assuming very steady seeing and an adaptive optics system a 45 meter ground-based telescope could resolve the lower stage of the LEM in theory.

Dave Mitsky