Could the Gov’t not do this? Does anyone know if this is done?
No need.
First, we already have several Spy sattelites going that were designed for spying on earth.
Second, the government would need to compensate the research teams that already have time reserved on the Hubble.
Hubble’s not built for it. The mirror’s about the same size as the existing spy satelites’, but the cameras and pointing mechanisms are all wrong.
As kbutcher said, there’s no need.
The Air Force launched a KH-11 “Improved” (also known as KH-12) just a few weeks ago on a Titan 4 rocket. (It had been scheduled for quite some time - current events did not affect the launch schedule, but clearly will affect its operation.) The United States acknowledges it has three large optical spy satellites in orbit.
Here’s the KH-11 “Keyhole” or “Crystal” spy satellite. Interestingly enough, the FAS’s link to data on the current state-of-the art, KH-12 “Improved Crystal” is broken. Hmmmm…
Here are some recent photos taken by American spy satellites.
The basic problem is that Hubble is not designed to track objects that move that quickly. It cannot even track the Moon, which moves far more slowly than an unsuspecting person on the ground.
Incidentally, Hubble does turn downwards and view the Earth. I have mentioned this before somewhere in the dark depths of the SDMB. It takes what are called “Earth flats” to calibrate the cameras. They are untracked and out of focus; houses, trees, etc. appear as long fuzzy streaks. I have seen them, and it is definitely weird to see something that must be a tree (though wormy and out of focus) in a Hubble image.
Is not the HST just a Key Hole class spy satellite redesigned to point “up” instead of down?
No. At the time Hubble was designed, Keyhole spacecraft were very secret (and they’re still pretty secret these days). Even though some of the companies that worked on Hubble also built the Keyholes, the compartmentalization within them (i.e. staff that worked on Keyhole were not permitted to work on Hubble, or even speak with those who did - a typical procedure in companies that do both civil and military work) was very strict. It was only because both spacecraft had to fit in the Space Shuttle that they turned out to be the same size and shape. Incidentally, the Space Shuttle was partially designed around launching the Keyhole spacecraft.
Edward Chaisson, in his book “The Hubble Wars”, mentioned a conversation he had “off the record” with somebody involved with Keyhole. He implied that several of the problems Hubble was experiencing in its early days (the misshaped mirror, the vibrating solar panels) had been encountered and fixed in previous Keyhole spacecraft. If Hubble was just a redesigned Keyhole, those problems would not have happened.
Sorry, that’s Eric J. Chaisson. He was the Media Director of the Space Telescope Science Institute (the astronomers who used Hubble). The book is Hubble Wars.
here are my neighbors Caught in the Act . . .
http://www.fundimension.com/pictures/showpictures.php?ID=341&cat=2
I could be wrong but I don’t think spy satellites ‘track’ anything. You point them at a spot on the ground and snap a photo. They may have some tracking ability that allows them to compensate for the camera’s motion across the sky while the photo is taken (so it’s not motion blurred) but I don’t think it can lock on to an individual and follow them around in real-time.
Also, I suppose you mean the moon’s apparent motion. I’m pretty sure I couldn’t walk around the earth along the path of the moon’s orbit in 30 or so days. Heck…I don’t think I could walk from Chicago to Los Angeles in that time!
OT-
Why are most spy sat pictures in black and white? Is it for a contrast reason or something?
That would be my guess. Contrast and shadows show up better on black and white. Color would be pretty useless information when all you’re interested in is the positions of things like buildings, radar stations, anti-aircraft guns, and so on.
Exactly. From the camera’s point of view, the ground is moving very fast. It must be able to find and follow a spot on the ground.
RE: Black and white:
The cameras collect light digitally. By collecting it all in a single grayscale rather than separating it out into three color bands, more shades of gray can be collected in the same bandwidth. More shades of gray means better contrast definition.
Incidentally, filters can be used, causing the camera to collect only portions of the spectrum. Hubble does this to create the “false color” images NASA often releases. It takes three shots of the same subject: one in red light, one in blue light and one in green light. Viewed separately, they would each look gray, because the camera only records brightness. But if you tint the image of each color band and combine them, you get a pretty picture in full color!