Last time I checked, there were over 20 different browsers for looking at Landsat 8 imagery alone and that was more than three years ago! There are also plenty more aerial and satellite imagery providers-I simply listed some of the largest ones. There are plenty of other places to get access to some of the datasets I mentioned above-especially the free ones. If you’re new to this world, the first thing to know is that you’re almost certainly going to have to speak with a salesperson-there’s no such thing as simple, transparent pricing in the satellite and aerial imagery world (at least not yet).įor slightly lower resolution but higher frequency imagery:įor aerial imagery in the U.S. We run into this situation quite frequently at Azavea, so we’ve gotten to know many of the providers over the years. Lastly, there’s the difficult case of needing high resolution, recently collected imagery (especially if you plan to derive commercial works from that imagery and need access to the raw files). That imagery can also be downloaded from either Earth on AWS or the Earth Engine Catalog-you can also browse when the most recent imagery was collected for each state (and at what resolution) at this free online coverage map hosted by ESRI. ![]() In the U.S., the USDA’s National Agricultural Imagery Program (NAIP) captures 1m/pixel or better imagery for the entire contiguous United States once every other year. Make sure you familiarize yourself with the data before downloading a lot of it!įor high-resolution aerial imagery, your options are much more limited. A warning: these are very large files and the imagery itself is lower resolution than what you might expect to see on a typical web map. MODIS (NASA’s satellite constellation which images the earth every 1-2 days)ĭata from all three of these satellite constellations can be downloaded for free from either Earth on AWS or Google’s Earth Engine Catalog.Landsat 8 (the USGS’s satellite which images the earth once every 16 days).Sentinel-2 (the European Space Agency’s constellation of satellites imaging the entire landmass of the earth once every five days).Here’s where things get interesting-we’ve written previously about the explosion of freely available, openly licensed, and constantly updating satellite imagery in our blog post, An Introduction to Satellite Imagery and Machine Learning. For larger-area basemaps, satellite imagery providers make more sense: and Australia and has a very simple user interface available through any web browser. For high-resolution aerial imagery, NearMap orthographics provide great coverage in the U.S. Rather than license imagery from Google that they’re, in turn, licensing from imagery providers, it usually makes more sense to go directly to the source. Google’s Maps API is notoriously stingy in this regard, with its terms of service even limiting your right to display content derived from Google imagery on a map that isn’t also provided by Google. tracing building footprints or other cartographic features), you should consider a paid option that allows for derivative works to be produced. If you’re considering deriving a commercial product from the imagery you’re browsing (e.g. He’s worked at Google for over 14 years and he gave me an aerial view (pun intended) of how satellite imagery works.Some other great sources of non-commercial, non-downloadable imagery are: To answer these questions, I reached out to our satellite imagery techspert, Matt Manolides. But how does satellite imagery actually work? How often are images updated? What are some of the biggest challenges to bringing satellite imagery to more than 1 billion users? Capturing the world from above is a huge undertaking, matching millions of images to precise locations. ![]() Today, satellite imagery is one of the most popular features on Google Maps. For most of human history, it was impossible to even imagine what Earth looked like from above, and only in the past century have we been able to capture it. It’s thrilling to watch cars move, see skyscrapers cast shadows on the street or check out the reflection of the sun in a body of water. (And I can’t wait to start flying again… or at least get out of my apartment.) Not because I’m annoyed by the beverage cart hitting my elbows (though I am), or because I like to blankly stare out at the endless sky (which I do), but because I enjoy looking down at the streets, buildings and skyline of my destination as we land. ![]() When flying, I am firmly a window seat person.
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