Happy Earth Day, space fans! Today marks the annual celebration of our home planet and if you're in the Washington, D.C. area, NASA has a slew of live events planned to highlight what makes Earth so special. NASA also has many online activities available for Earth fans, including its "Global Selfie" campaign to reach out across the social network universe.

"NASA will celebrate the 44th anniversary of Earth Day with a variety of live and online activities April 21-27 to engage the public in the agency’s mission to better understand and protect our home planet," agency officials wrote in a statement. "This year, for the first time in more than a decade, five NASA Earth Science missions will be launched into space in the same year. These new missions will help address some of the critical challenges facing our planet today and in the future: climate change, sea level rise, access to freshwater resources, and extreme weather events." [NASA's Earth Right Now: Earth Science Missions for 2014]

Scroll down for a list of NASA Earth Day activities (courtesy of NASA), as well as a schedule of live events at Union Station in Washington, D.C.:

 Earth Day in the Nation’s Capital
Tuesday, April 22 (10 a.m. - 6 p.m.) -- NASA Hyperwall and Science Gallery exhibits in the main hall of Union Station at 40 Massachusetts Ave., NE. The exhibit will include activities and displays showing how NASA uses satellite technology to better understand our changing planet. NASA scientists will give a series of talks April 22 at the Hyperwall stage. For a complete listing of events, visit: http://go.nasa.gov/1kIrbtX

NASA #GlobalSelfie Event
Join NASA April 22 as we encourage people all over the world to step outside and celebrate environmental awareness. Anyone, anywhere on the globe, can participate by posting a "selfie" with their local environment as a backdrop. Post your photo to Twitter, Instagram or Google+ using the hashtag #GlobalSelfie or to the event groups on Facebook and Flickr. Photos tagged #GlobalSelfie will be used to create a mosaic image of Earth. For details on how to participate, visit: http://www.nasa.gov/globalselfie/

NASA Center Activities

Stennis Space Center, Hancock County, Miss., April 22 (10:30 a.m. - 3 p.m. CDT) -- Demonstrations and hands-on activities will be part of the center's Earth Week at Infinity Science Center. School groups and the general public will be able to participate in the solar beads bracelet activity, tornado in a bottle experiment, Science on a Sphere presentations, and Experimentation Station demonstrations. For more information, visit: http://www.visitinfinity.com/

Jet Propulsion Laboratory(JPL), Pasadena, Calif., April 22 (8 p.m. PDT) -- Theater Arts Caltech will present a special Earth Day production of the play "Dr. Keeling’s Curve," starring Mike Farrell, in the California Institute of Technology's Ramo Auditorium in Pasadena. The play tells the story of the scientist whose research on carbon dioxide provided the first early warnings about global warming. Tickets must be purchased for the play performance, but a 9:30 p.m. post-performance climate change discussion that includes JPL scientists is free of charge. More information is available at: http://www.caltech.edu/content/mike-farrell-dr-keelings-curve

Aquarium of the Pacific 14th Annual Earth Day event, Long Beach, Calif., April 26 and 27 (9 a.m. to 5 p.m. PDT) -- JPL will host a booth in the main hall for this event, which focuses on Earth as an ocean planet. The event includes hands-on learning demonstrations for all ages. For more information, go to: http://www.aquariumofpacific.org/events/info/earth_day_celebration/

Full NASA Earth Day Schedule at Union Station in Washington, D.C.:

NASA Hyperwall Presentations: April 22

NASA's Hyperwall displays large visuals that provide new perspectives of Earth's environment, the sun, our solar system, and beyond. All times EDT.

11:00 a.m.
Welcome and Opening Remarks -- Kathryn Roger, Earth Day Network; Michael Freilich, Earth Science Division, NASA Headquarters; Gwen Camp, Federal Emergency Management Agency; Mark Polhemus, Union Station

11:15 a.m.
NASA's View of Earth from Space -- Jack Kaye, NASA Headquarters

11:30 a.m.
Believe It or Not, Spring is Coming Earlier -- Compton Tucker, NASA Goddard Space Flight Center

11:45 a.m.
Changes in the Antarctic Peninsula -- Chris Shuman, NASAs Goddard Space Flight Center

12 p.m.
Measuring Rain and Snow for Science and Society -- Dalia Kirschbaum, NASA Goddard Space Flight Center

12:15 p.m.
Our Planet is Changing: Perspective from Space -- Michelle Thaller, NASA’s Goddard Space Flight Center

12:30 p.m.
2014: A Big Year for Earth at NASA -- NASA Administrator Charles Bolden, NASA Headquarters

12:40 p.m.
Continuing the 40-Year Legacy with Landsat 8 -- James Irons, NASA Goddard Space Flight Center

12:55 p.m.
Protecting Earth from Solar Storms -- Lika Guhathakurta, NASA Headquarters

1:10 p.m.
Observing Earth's Poles -- Tom Wagner, NASA Headquarters

1:25 p.m.
Measuring Air Pollution from 440 Miles Above the Earth's Surface -- Edward Celarier, NASA Goddard Space Flight Center

1:40 p.m.
Eyes on the Earth 3D: Come Fly With NASA -- Kevin Hussey, NASA Jet Propulsion Laboratory

1:55 p.m.
The Universe in Earth Day -- Rachel Osten, Space Telescope Science Institute

2:10 p.m.
Earth’s Biodiversity: The View from Space -- Allison Leidner, NASA Headquarters

2:25 p.m.
Hubble and Spitzer's Frontier Fields -- Dan Coe, Space Telescope Science Institute

2:40 p.m.
Journey to Mars -- Michelle Thaller, NASA Goddard Space Flight Center

2:55 p.m.
NASA's Search for Other Earth-Like Worlds -- Debra Wallace, NASA Headquarters

3:10 p.m.
Looking Homeward -- NASA Chief Scientist Ellen Stofan, NASA Headquarters

Hands-On Demonstrations: April 21-22

Dynamic Planet -- This touchscreen interface allows users to drive a spherical display that shows a variety of remote-sensing satellite datasets.

Eyes on the Earth 3D: Come Fly with NASA -- A 3D visualization experience that lets users "fly along" with NASA's fleet of Earth science missions and observe climate data from a global perspective in an immersive, real-time environment.

What on Earth? -- Look closely at these Earth photos to determine just what on Earth it is. (April 22 only)

Space Racers -- A new animated television program following young Space Rocket cadets as they soar through the solar system learning about scientific investigation and observation, space exploration, and the importance of working together as a team. Visit the Space Racers Kiosk for an exclusive sneak peak of our new "Space Collector" game.

Science Casts -- Short videos about interesting and unusual science topics encountered by NASA's science missions. New episodes every week look into the science behind discoveries on Earth, the solar system, and beyond. Learn more at sciencecasts.nasa.gov.

iSat -- The Interactive Satellite Tracker is a browser-based application that allows you to track all NASA science satellite missions, as well as other satellites.

Calculate Your Carbon Footprint -- Discover where you fall on the "Green-o-Rometer." We’ll even offer simple tips on ways to reduce your carbon consumption.

UV-Detecting Beads -- NASA keeps a close eye on the sun’s ultraviolet (UV) radiation and you can too. Become a UV detective with specially designed UV-sensitive beads and walk away with your own UV-detection bracelet.

Learning Remote Sensing with Puzzles --Help NASA piece together images taken of Earth from space, including the popular "Earth at Night" image.

Know Your Earth -- How well do you know your home planet? Take a quiz and earn a prize if you correctly answer each question. Through these quizzes, you can learn all about NASA Earth Science.

Digital Photo Booth -- Get your face in space and walk away with a real keepsake.

Earth Connection via Suborbital Platforms -- Navigate your way through NASA science and explore various research platforms using two touchscreen kiosks. Touch the materials used to make NASA's scientific balloons and inflate a cylinder made of the balloon film to observe how the material behaves while the cylinder expands.

The Earth Imagery Challenge -- NASA satellites are taking measurements of planet Earth from space every day. Follow our "clues" to solve the imagery mystery.

Sensors, Circuits, and Satellites --Assemble an energy-sensing circuit and discover how NASA's Aura satellite studies the chemistry of our atmosphere.

Cloud in a Bottle: GLOBE Program -- Learn about clouds and make a cloud in a bottle. Then play our Cloud Cover Estimation game. (April 22 only)

Puzzling Changes in the Land -- Arrange a time series of Landsat images or piece together a Landsat scene to reveal Earth's changing landscape.

Aviation and the Environment -- What would happen to us if our atmosphere suddenly disappeared? Learn how pilots and astronauts protect themselves as they travel to the very edge of Earth's atmosphere.

Measuring Precipitation:On the Ground and From Space -- Learn how rain gauges work, how the technology of the new Global Precipitation Measurement (GPM) satellite measures precipitation from space, and why it's important to look at precipitation patterns around the globe.

For more information about the Union Station event, visit here.

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