Myth Dispelled: HST can observe the moon

statickid

CatDog from Deimos
Donator
Joined
Nov 23, 2008
Messages
1,683
Reaction score
4
Points
38

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
37,588
Reaction score
2,312
Points
203
Location
Wolfsburg
Preferred Pronouns
Sire
I thought the myth was, that Hubble should be seeing the moon and prove that nobody landed there, but the evil US gov is not allowing that.
 

Eccentrus

Geekernaut
Joined
Jun 26, 2009
Messages
859
Reaction score
27
Points
28
Location
Jakarta or Bandung
well it can, but it is more economical and utilizes its potential to a more full capacity when it's observing stars, well things like the HST have a limited lifetime and so every second counts, that's why it only looks at the earth or moon only for calibrating, observation that is useful for its life cycle, and can sometimes be beautiful as well. Either way, the less of a photographer probes that we send there actually send much more meaningful data since they also elicit the topography and surface gravity of the object of study itself, and hence the relative disinterest of the moon by the HST team.
 

Izack

Non sequitur
Addon Developer
Joined
Feb 4, 2010
Messages
6,665
Reaction score
13
Points
113
Location
The Wilderness, N.B.
I had thought that it was because Hubble can't track objects with apparent motion as large as the Moon's. I guess the nature of the myth is another myth.
 

MattBaker

New member
Joined
Jul 9, 2011
Messages
2,750
Reaction score
0
Points
0
Thought the same like Izack, too since the HST is travelling with 7500 m/s around the Earth. I'm not sure if you can make a stable image with that, but since we're on the internet here's the obligatory xkcd. (With that link to this photo stating that the exposure time was just half a second.)
 

Astronut25

New member
Joined
Nov 17, 2009
Messages
102
Reaction score
0
Points
0
Location
Out there
http://what-if.xkcd.com/32/

the HST can take a look at the Moon, the gyroscopes can barely keep up, and since the HST is designed to look at distant objects, it is very farsighted. Any image of the Moon would not be of great quality, and the Earth would be just a blur.

:ninja:'d, why didn't my web browser show the last post? I guess thats what I get for using IE. :firefox:
 
Last edited:

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
37,588
Reaction score
2,312
Points
203
Location
Wolfsburg
Preferred Pronouns
Sire
What happened to the former spy satellites? They will have Earth observation gyroscopes and are just not permitted to look at Earth... but could observe to moon easily.
 

N_Molson

Addon Developer
Addon Developer
Donator
Joined
Mar 5, 2010
Messages
9,272
Reaction score
3,244
Points
203
Location
Toulouse
Who can the most can usually do the less.
 

MattBaker

New member
Joined
Jul 9, 2011
Messages
2,750
Reaction score
0
Points
0
What happened to the former spy satellites? They will have Earth observation gyroscopes and are just not permitted to look at Earth... but could observe to moon easily.

You mean the ones "donated" by the NRO last year? [ame="http://en.wikipedia.org/wiki/2012_National_Reconnaissance_Office_space_telescope_donation_to_NASA"]Wikipedia[/ame] has an article on that stating they could be used as a Wide Field Infrared Survey Telescope (WFIRST) to search for exoplanets and dark energy. But due to the JWST it's currently NET late 2010's (so 2026).
 

garyw

O-F Administrator
Administrator
Moderator
Addon Developer
Tutorial Publisher
Joined
May 14, 2008
Messages
10,485
Reaction score
209
Points
138
Location
Kent
Website
blog.gdwnet.com
I had thought that it was because Hubble can't track objects with apparent motion as large as the Moon's. I guess the nature of the myth is another myth.

No myth. It's true. They have to point hubble 'ahead' of where the moon will be then take the image as the moon dashes past.

The Moon is not too bright for Hubble. Funny though, it is hard to observe by HST, but that’s actually because it’s moving too fast in the sky. Hubble isn’t designed to track that quickly, so what they do to observe it is put it in “ambush mode”: Aim Hubble in the sky where the Moon will soon be, then wait. When the Moon moves in, Hubble grabs the snapshot. This has been done many times, actually (like in 1999 and 2005).

Source: http://www.slate.com/blogs/bad_astr...n_the_crater_tycho_up_close_and_personal.html
 

RisingFury

OBSP developer
Addon Developer
Joined
Aug 15, 2008
Messages
6,427
Reaction score
491
Points
173
Location
Among bits and Bytes...
HST can observe the Moon... ish.

The "too bright" thing is nonsense. All you need to do to counter that is to shorten the exposure time. What makes it difficult for Hubble to observe the Moon is that the Moon is in orbit around Earth and moves around at a certain velocity. To compensate for that, you need to rotate Hubble as it takes its image and that's where the problem lies: Hubble can't actually spin very fast. It's been designed to stare at the same spot for weeks. That means to keep it stable, it needs to make very small adjustments. It's incapable of making quick ones and keep control of itself...
 

statickid

CatDog from Deimos
Donator
Joined
Nov 23, 2008
Messages
1,683
Reaction score
4
Points
38
I thought the myth was, that Hubble should be seeing the moon and prove that nobody landed there, but the evil US gov is not allowing that.

Yeah I've heard that one too, :lol: I just though I'd post this since I did see someone saying specifically it was too bright some time ago (don't remember what discussion). I didn't know any different, never bothered to research it or anything. Figured I'd stash this article in our forum search archive for future generations.
 
Top