#Google maps satellite archive
#Google maps satellite series

Google’s new satellite map ultimately gobbled up more than a petabyte of imagery data. Mosaicking is computing-intensive: It has only flourished in the past three years due to industry-wide improvements in cloud infrastructure. When writing about a mosaicked map of the United Kingdom produced by the startup Mapbox in May 2013, the journalist Tim Maly wrote: “At no point in the history of the United Kingdom has it looked like this. Matt Hancher, an engineer, called the process a “glorified computation of the median.” The company’s Maps and Earth team has used a mosaicking algorithm to generate its satellite map since June 2013.Īn odd characteristic of the mosaicking process is that it captures the essential character of what a place looks like even though it actually encompasses years of data. Google’s version of this algorithm factors in other special circumstances, like seasonal effects. The team analyzed more than 700 trillion pixels of satellite data in the entire mosaicking process. Eventually, these “best pixels” are stitched together into a single map-a mosaic. Then it runs that program for the next pixel.

Then it drops the images that are much lighter than that average-since they likely include clouds-and averages the most recent set of remaining, now-cloudless photos to find a final color value.

#Google maps satellite archive

(If the archive is properly calibrated, that one pixel should describe the same spot of Earth no matter when it was taken.) In essence, the algorithm takes an initial average color value for that pixel over time. Mosaicking joins the cloudless parts together through the power of surprising, elegant math.Ī mosaicking algorithm inspects each pixel of imagery individually-across all of the images of that particular pixel collected by Landsat 7 and 8. Over time, though, very few places are completely obscured by clouds. This makes sense: About 70 percent of Earth’s land surface is covered by clouds every day. Taken individually, most of these pictures captured by the Landsat sensors include some clouds. (Landsat 7 and Landsat 8 are only the most recent of these craft.)

#Google maps satellite series

government’s Landsat program, a series of satellites that have photographed the Earth’s surface every 16 days since the 1970s. Mosaicking draws upon the vast archives of imagery that have been created by the U.S. Instead, Google engineers used a recently developed cartography technique called mosaicking. Neither of the images above were captured on a single shoot by a solitary satellite, the way that a camera might capture a snapshot. This “ghostly” runway effect points to how Google makes its maps cloudless in the first place. Its remoteness gives it a unique ecology, but-given its location in the middle of the tropical Indian Ocean-it is frequently obscured by clouds. Almost a thousand miles from Australia, the island was largely untouched by human settlement until the past two centuries.

The improvements can be seen in the new map’s depiction of Christmas Island. Google had not updated its low- and medium-resolution satellite map in three years. Most importantly, this new map contains fewer clouds than before-only the second time Google has unveiled a “cloudless” map. The new map, which activates this week for all users of Google Maps and Google Earth, consists of orbital imagery that is newer, more detailed, and of higher contrast than the previous version. Google has added nearly 1.5 trillion pixels of new data to its service *.

On Monday, it gets a makeover, and its many users will see something different when they examine the planet’s forests, fields, seas, and cities. More than 1 billion people use Google Maps every month, making it possibly the most popular atlas ever created.