this post was submitted on 24 May 2024
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Just curious how they get the satellite pictures. Do they have their own? Is there an open-source option or public availability of satellite pictures somewhere?

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[–] [email protected] 16 points 2 months ago

The image sources are presented in the bottom right corner of the screen when looking at Google Maps in a browser. Check there to see where the images you are currently looking at come from.

[–] [email protected] 5 points 2 months ago

All good stuff, thank you.

[–] [email protected] 7 points 2 months ago (3 children)

As a follow-up question, what are some open source satellite data sources, maybe orgs like NASA?

[–] [email protected] 11 points 2 months ago* (last edited 2 months ago)

For optical images you want Sentinel-2 (EU) with 10m Resolution or Landsat 8 (NASA) with 30 m resolution. You can use the Copernicus Open Data Hub and the The USGS earth explorer for download, they offer graphic inferfaces where one can select an area of interest or upload shapefiles.

There are many more data sources, specialized software and/or APIs for Python for batch downloading etc.

When you have downloaded the data, you can use different programs for visualizing and georeferencing the images such as QGIS.

Keep in mind the work with satellite remote sensing data is not trivial and usually requires many postprocessing steps. If you just want to explore the earth surface I would recommend to look for local ortho images from aerial photography. Depending on where you live, this data will be made available for download and/or exploration via a web mapping service (WMS). It is much more detailed and may be more interesting you, and a bit less complicated than satellite data.

Just to be complete as you asked for satellite data in general: Of course there is much more available than just RGB channels. You can get more band e.g. Near Infrared from Sentinel-2, or cool stuff like RADAR from Sentinel-1, LIDAR from GEDI etc. There are plenty of satellite missions for all your desires.

For anyone who wants to dive more into these topics, search for satellite remote sensing. You can also find many tutorials for processing this data e.g. using Python or R.

[–] [email protected] 2 points 2 months ago

Sentinel data from Copernicus is free and of better spatial resolution than Landsat.

[–] [email protected] 3 points 2 months ago

Awesome question. I don't have an answer, but maybe try LandSat? It's NASA. Between general map enthusiasts and geocaching and who knows how many other geographical hobbiests out there, there's got to be something open source.

[–] [email protected] 2 points 2 months ago
[–] [email protected] 21 points 2 months ago

Check out Planet Labs, BlackSky, Maxar, and Spire Global. They all operate private fleets of satellites, if you have the budget they will sell you the data.

[–] [email protected] 20 points 2 months ago (1 children)
[–] [email protected] 11 points 2 months ago

They spun out their satellite operations as an independent company named Planet Labs awhile back, it went public a few years ago.

[–] [email protected] 48 points 2 months ago (1 children)

Google has either purchased local map data from established companies, or has entered into lease agreements to use copyrighted map data. The owner of the copyright is listed at the bottom of zoomed maps. For example, street maps in Japan are leased from Zenrin. Street maps in China are leased from AutoNavi. Russian street maps are leased from Geocentre Consulting and Tele Atlas.
They also use images from the LandSat 8 satellite.

[–] [email protected] 21 points 2 months ago (2 children)

In addition, the high resolution ones where you can see individual houses and the like when super zoomed in are interestingly often not satellite derived, but from things like airplanes or drones. Ones with just Google (or no specific company) listed as the copyright holder will definitely fall under that as they don't have their own satellites, others might on a case by case basis.

[–] [email protected] 3 points 2 months ago

Ones with just Google (or no specific company) listed as the copyright holder will definitely fall under that as they don't have their own satellites

Which, in a way, I find kind of surprising. Google do just about everything else, it seems like having their own satellites wouldn't be an unrealistic thing for them. Maybe it's not worth it when they can just buy imagery from established players.

[–] [email protected] 3 points 2 months ago

Great point, and definitely important.
Google has also bought various companies over the years that already have the info and or the means to get the info. A deep dive historical video essay could be really interesting on all of this.