Theoretical Resolution of Hubble

[Space259]

It's quite simple Physics to show that the moon landing sites cannot be imaged by Hubble as its angular resolution is too small. So how come:

"Prof Steve Beckwith Director Hubble 1998-2005

"we could easily image the light from a firefly at the distance of the moon"

What am I missing here?

 

[pixel01]

Yes. I think the author meant the Hubble can detect the lighting bug at that distance because it is very sensitive. But if there are 2 bugs at that distance and about 100m apart, Hubble will see them as one source of light.

 

[russ_watters]

pixel01 is correct, but to add:

It is important to remember that cameras can take pictures of dim objects by essentially leaving the shutter open as long as you wish to gather up enough photons to make an image. The Hubble can spend weeks taking a picture of a single object to gather up enough photons to make it detectable.

 

[nanoWatt]

Is weeks how long it took to take the Deep Field image?

 

[pixel01]

Is weeks how long it took to take the Deep Field image?

Per my memory, the exposure time for the Ultra DF Image was about 29 days !

One of very important device of the Hubble TS is the Fine Guidance Sensor which is designed to lock the telescope onto the target.

 

[russ_watters]

http://hubblesite.org/newscenter/archive/releases/2004/07/