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Hey over there, I can see you! Where you ask? EVERYWHERE! I just pull it up from a satellite.
Hey gang, Trace here for DNews! There was a time when satellite imagery was conspiracy
talk, only available to high-level government officials, or, like, spies. But thanks to
Google Maps and Apple Maps, and Bing Maps, and Mapquest and the dozens of others out
there we can see satellite images every day! For FREE!
Though we just use them to find the nearest thai restaurant… the process of getting
them into your phone is INVOLVED, man. The first reconnaissance, or spy satellites were
the Corona satellites launched in the 1960s. They had film cameras on board, and to get
that film back to earth, they ejected it with a parachute and had to go pick it up! The
Air Force would try and snag it out of the air, or the Navy would sail over once it hit
the ocean.
These early experiments taught us how to take pictures from a moving satellite of a moving
planet while 100 miles up. For example, the lenses on the Corona satellites rotated constantly
to keep the shot steady. They even tried angling two cameras to capture a stereo image! Spy
satellites were so good at grabbing images without letting the spyees know what was up,
the United States and other nations continue to use them!
But when Google acquired satellite imaging company Keyhole in 2004, they changed the
whole game. Now anyone could look down on the planet and make comments. They still blur
sensitive areas, as required by world governments, but mostly the images we're seeing are WAY
better than the ones we used in the 60s to determine how to avoid World War Three.
Today, the actual satellite images are taken by companies like TeleAtlas, DigitalGlobe,
EarthSat, Skybox, and others. They're then sold or licensed to governments and companies
for geology, mapping, urban planning, shipment tracking… the applications are endless.
This is why some of the images on satellite maps are lower resolution than others. Each
company is working with different equipment and regulations keep the companies from scanning
faces, backyards or license plates.
A few months ago, regulators loosened restrictions on U.S.-based DigitalGlobe. So last week,
they launched the WorldView-3 satellite, their highest resolution sat ever. Which means,
in a few weeks, maps could see images with a resolution as high as 25 centimeters! Basically,
they'll be able to see a piece of paper, but not read it. They WANT to launch sats with
10 cm resolution, about the size of your phone screen. Google says the data on their maps
are updated as often as possible, so though they're not LIVE, some images are as new as
two weeks old, and none are older than three years. Which means this new, high-res 25 centimeter
imagery might be appearing soon. Each mapping company is in charge of stitching the images
into one, giant map, adding the locations of interest and keeping it regular.
But speaking of real time data; that stuff is notoriously locked up. Remember, the satellites
are moving, the planet's moving… viewers of live images can only see what the satellite
is looking at during any particular moment, and moving a sat to look at your ex's driveway
isn't really practical. But a NASA program called EarthKAM is letting students get access
to real time space cameras -- not via spy sats, but via a camera right on the international
space station!
Schools around the world are signing up students by the thousands to explore our planet using
live images, because there's just something about seeing this information in real time,
amirite? Students of the Sally Ride EarthKAM program can directly control the camera, taking
pictures of the Earth and analyzing human geography, geology, ecology, and global change!
They even learn about space operations and do flight control simulations! Sign me up!
How do you feel about satellites getting more accurate images? Freaked out? Excited?
Go on, let loose in the comments and be sure you subscribe for more DNews, seven days a
week. And as long as you're in a clicking mood, click here or on the link in the description
to RSVP for our next SpaceOut on August 27th at 4pm Pacific! Each month, Ian O'Neill and
I get together and hangout with experts from NASA/JPL to talk space. This month, it's about
Europa! Planned robotic missions, possibilities of alien life, and cutting through ice millions
of miles away! It's going to be awesome. RSVP now, so you don't get lost on the way. Thanks
for watching!