Looking for something to do on Earth Day, April 22nd? NASA has a plan for a global selfie, and they want you to be a part of it. Here’s how. NASA plans to celebrate Earth Day and the fact that five missions are launching to better study the Earth by compiling a massive selfie of the planet taken by the people who inhabit it. The final product will be a mosaic of the planet pieced together from all the photos posted to social media (Twitter, Instagram, Facebook, Google+, and Flickr) on April 22nd with the hashtag #GlobalSelfie. Along with the hashtag, NASA also wants you to include your location, and they’ve mocked up this handy sign you can print out and include in your pic. via Geekosystem.