The first Landsat satellite was launched in 1972. That's 41 years ago, if you're counting. And if you're counting, it's also worth mentioning that there have been a total of seven Landsat satellites, including the one that launched yesterday from Vandenberg Air Force Base in California, Landsat 8.
You may have noticed that Landsat 8, being the seventh satellite, doesn't quite add up. That's because Landsat 6 didn't make it to orbit back in 1993. Even with that gap, NASA and NOAA have had nearly four solid decades of multispectral images of the surface of our planet. That includes a record-breaking operational mission of 29 years by Landsat 5, which is somehow still up there, although it'll be on its way down soon to make room for this new bad boy, Landsat 8.
Landsat 8, like all of the Landsat spacecraft, will spend a minimum of five years adding to the massive catalog of millions of pictures of Earth taken by its predecessors. It covers the entire planet once every 16 days, using a nine-band multispectral sensors along with a dual-band thermal imager to make a record of, among other things, how badly humans are screwing up the environment. Or, very occasionally, not screwing it up.
What Landsat does better than anything else, and why it's so important to have up there, is provide a detailed record of how Earth changes over time. Each band of the sensing system is tuned to detect specific features, including soil, vegetation on slopes, vegitation not on slopes, vegetation near water, vegetation that's been burned, vegetation that's being burned, vegetation that's feeling just a little bit stressed out (seriously), water currents, and clouds. By looking at these bands and comparing years or decades, scientists can detect changes that take so long to manifest that we'd otherwise miss them completely. And thanks to spectral classification, Landsat enables us to accurately measure things like how much rainforest we hack into mulch every year, or the rate of urban growth throughout the world, or how much rainforest gets hacked into mulch to enable urban growth. This is seriously important stuff.
The $855 million Landsat Data Continuity Mission (LDCM), which will be officially called Landsat 8 as soon as it shows itself to be up and running, was launched (somewhat gloriously) from Vandenberg Air Force Base along the central California coast yesterday. The reason that Vandenberg is used for some satellite launches while Cape Canaveral in Florida is used for others is generally because rockets aren't allowed to fly over populated areas while in boost phase, just in case something goes wrong. So, from Florida, you can launch stuff off to the East out over the Atlantic ocean as much as you want, but if you want to put a satellite into an orbital trajectory that requires a launch to the West, you have to head over to Vandenberg to take advantage of the vast expanse of the Pacific ocean.
To reach an orbital altitude of 438 miles, Landsat 8 relied on an Atlas V main stage with a Centaur upper stage. DVICE got to check out the Atlas V rocket on the pad at Vandenberg on Sunday, and then we hung around for the launch on Monday morning. We got some pretty decent pics of the rocket going up from a little over two miles away (which as close as they let you get without armor and a sturdy umbrella or something), and you can check them out (along with some vids of the event from NASA) in a nice big gallery below.
Oh, and if you like all this Landsat stuff, the entire catalog of imagery is available in easily-browseable format here.
Via Landsat 8