Preservation of satellite imagery

[bugo]

What happens to the old information when, say, Google updates Google Maps?  Does it fall into the memory hole?  Or is it archived somewhere?  It would be nice to be able to enter a date and it would show the maps as they were on that date.  Same with Street View.  It should also be archived.

[mass_citizen]

I was wondering that the other day, particularly when I clicked an old link in a thread to see an old sign and it had since been replaced.

[Urban Prairie Schooner]

Google Earth has the ability to toggle between the current imagery and imagery from past years. Usually superseded imagery can be made visible using that tool. As for Street View, I don't know but it would be nice to have the same ability to bring up older images.

[getemngo]

Google Earth has the ability to toggle between the current imagery and imagery from past years. Usually superseded imagery can be made visible using that tool. As for Street View, I don't know but it would be nice to have the same ability to bring up older images.

Oh wow, I didn't know that! I'd been using MSR Maps (former Terraserver-USA) for old imagery, where it's permanently the 1990s, but unfortunately, so is the navigation.

[1995hoo]

.... Or is it archived somewhere? ....

NSA.

[froggie]

I know the zoomed-in imagery on Google Earth and Google Maps (amongst other programs) is pretty detailed and high-res, but a lot of the 1-meter resolution imagery comes from the National Agriculture Imagery Program, an ongoing/annual program of the USDA.  Their data gateway has color imagery going at least back to 2003, but you need to A) download it, and B) have a way to view MrSID files in order to view it.

I use it for my ongoing GIS projects and GIS-created maps.

[cpzilliacus]

What happens to the old information when, say, Google updates Google Maps?  Does it fall into the memory hole?  Or is it archived somewhere?  It would be nice to be able to enter a date and it would show the maps as they were on that date.  Same with Street View.  It should also be archived.

I cannot speak to that.

I did work with some of the earlier efforts at unclassified imagery of the earth, taken by Landsat 1, 2 and 3 in the 1970's.   Analog images converted to film and digital formats.  I believe most or all of it is archived at the USGS Eros Data Center in Sioux Falls, South Dakota.

[cpzilliacus]

.... Or is it archived somewhere? ....

NSA.

Unlikely.  If a U.S. intelligence agency is storing it, it's the NGA, located down in your part of the world off of Va. 286.

[agentsteel53]

What happens to the old information when, say, Google updates Google Maps?  Does it fall into the memory hole?  Or is it archived somewhere?  It would be nice to be able to enter a date and it would show the maps as they were on that date.  Same with Street View.  It should also be archived.

in fact, I would like this augmented by information that was never on Google Maps.  wouldn't it be nice to move a slider to "1955" and have all the aerials of the half-built Los Angeles freeway system available for perusal?  I know the CalTrans library has the originals.

[Scott5114]

There is a website for that, http://historicaerials.com/

Don't worry if you can't spell "aerial", http://historicarials.com/ redirects there too, so you won't accidentally end up on a site devoted to instances of poor font usage throughout the years.

[agentsteel53]

ouch, needs Silverlight.

Flash was already mediocre enough, why did we as a society decide we needed an even more mediocre clone of it?

[Duke87]

We as a society did not decide that. Microsoft did.

Historicaerials is nice as a way to look back in time but its collection is far from exhaustive. The thing about aerial and satellite photos from before the days of digital photography is that a lot of it still has yet to be digitized and is only available physically in libraries or government archives. Or was taken by private companies that don't care about preserving it. When I was in high school there was someone at the career fair one year who worked for a private aerial survey company. Turns out the guy was friends with one of my teachers and after some discussion he unloaded a bunch of old photos on me (mostly undated and unlabeled, fun!) along with a bunch of old USGS topos. I thought this was ridiculously generous of him at the time, but I later realized it was all stuff that would have gone in the garbage had it not gone home with me.