No, not Terra the Earth, Terra the satellite. NASA's Earth-observing bird first opened its eyes on February 24, 2000, and for the past decade has been dutifully watching our planet. It has looked upon us at different wavelengths, different resolutions, at different times of day, and different times of year. It has tracked changes, and reported back what it has seen.
And oh, what it has seen! Here is a map made almost entirely of Terra data (small gaps in some coverage were filled with data from GOES weather satellites):
Click to get the massive 85Mb 5400x2700 pixel image. It's totally worth it. Our planet is very, very pretty.
But Terra is more than just a camera. The data it returns track a lot of key environmental factors for our world. Here are representations of some of the data it takes: growing vegetation, carbon monoxide, aerosols (pollution), elevation, and net radiation (energy in from the Sun and energy radiated away as heat).
Again, click through to see how lovely data can be, or at least how it can be represented.
These maps, these observations, help us understand our own world, how it works, and how we're changing it. These are all matters related to our very survival, and I'm very glad we have tools like Terra helping us ensure that.
Image credits: Marit Jentoft-Nilsen (image) and Robert Simmon (globes)