“There’s a whole world out there, right outside your window. You’d be a fool to miss it.” These words by Swedish writer Charlotte Eriksson are like a mission statement for the Nasa Earth Observatory (EO).
![The Yukon River Delta spreads out across a vast tundra plain in southwest Alaska. Photo / Nasa](https://www.nzherald.co.nz/resizer/v2/7JP2HVYUSFCFJIJDOQE5NLOUJM.jpg?auth=c0c7b342c8841c3ac805ce23a7ac8087b27af7d85936716ee20a58366254379b&width=16&height=16&quality=70&smart=true)
Twenty-five years ago, America’s National Aeronautics and Space Administration (Nasa) launched its Earth Observatory website, sharing more than 18,000 image-driven stories of our planet from a new perspective. Subjects range from environmental issues to land use, from climate change to natural disasters and even just amazing stories of natural processes occurring around the globe.
![Polar mesospheric clouds during one of 16 sunsets observed on the International Space Station each day. These high-altitude clouds are formed by water vapour freezing into ice crystals in the mesosphere at about -130C. Photo / Nasa](https://www.nzherald.co.nz/resizer/v2/YH3T46QWXZGYLHPDDBAIB7S5BI.jpg?auth=d59c64b3bd8ba55535bdd59a7350e5c03945fd2f16bf29f9b49d2ca9ebb92632&width=16&height=11&quality=70&smart=true)
Albert Einstein wrote, “Look deep into nature, and then you will understand everything better.” The Nasa Earth Observing System of polar-orbiting and low-inclination satellites allow us to examine the land surface, biosphere, atmosphere and oceans to gain a better understanding of the systems and processes of nature, enabling an understanding of the Earth as an integrated system.