For Earth Day 2021, we explore the connections of Earth systems and NASA's ability to observe them in a changing world, highlighting the links between dust transport, vegetation, water quality, conservation and human health, the cryosphere, and disasters.br br Music: "Ellipsis" and "Terrafirma" by Ben Niblett and Jon Cotton [PRS] via Universal Production Musicbr br Video credit: NASA's Goddard Space Flight Centerbr Jefferson Beck (USRA): Lead Producerbr Ellen T.