There are several events held today through April 27 by the National Aeronautics and Space Administration to mark the 44th anniversary of Earth Day.

To begin with, the space agency is launching five Earth Science missions this year to help address some of the critical challenges facing the earth today and in the future, such as climate change, rising sea levels, access to freshwater resources, and extreme weather.

Earth Day in the Nation's Capital - Today, April 22, from 10 a.m. to 6 p.m., the NASA Hyperwall and Science Gallery exhibits in the main hall of Union Station at 40 Massachusetts Ave., NE. The exhibit includes activities and displays that demonstrate how NASA uses satellite technology to better understand the changing planet. NASA scientists will offer a series of talks. Visit https://go.nasa.gov/1kIrbtX for a complete listing of events there.

NASA #GlobalSelfie Event - NASA encourages Earthlings all across the world today to step outside and celebrate environmental awareness by snapping a "selfie," otherwise known as a photo of oneself, with anything at all iin the local environment as the background. Participants can post their photos 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: https://www.nasa.gov/globalselfie/

NASA/JPL - At the Jet Propulsion Laboratory in Pasadena, Calif.,starting at 8 p.m., 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 depicts the story of the scientist whose research on carbon dioxide provided the first early warnings about global warming. JPL scientists will participate in a post-performance discussion session. More information about the performance and later discussion is available at: https://www.caltech.edu/content/mike-farrell-dr-keelings-curve.

Aquarium of the Pacific - The 14th Annual Earth Day cdelebration at the Long Beach, Calif., aquarium takes place April 26 and 27, from 9 a.m. to 5 p.m. both day. The Jet Propulsion Laboratory will host a booth in the main hall during the two-day event, which, which focuses on Earth as an ocean planet. The event includes hands-on learning demonstrations for all ages. More information is availabile by visiting: https://www.aquariumofpacific.org/events/info/earth_day_celebration/.

Stennis Space Center, Hancock County, Miss. - From 10:30 a.m. to 3 p.m., there will be demonstrations and hands-on activities as 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. More information on the event is available at https://www.visitinfinity.com/.