Although a large fleet, the satellites will provide only half of today's observational capacity once aloft. The current EOS orbiters are the result of the NASA's Decadal Survey for Earth Science, which prioritizes its research missions. But the forthcoming flights, Abdalati says, are mostly single instruments with fewer capabilities than the current system. For example, Terra and Aqua, launched in 1999 and 2002, respectively, carry multiple instruments on their platforms and are the largest satellites NASA ever launched, according to Markus.
The primary reason for the demise of what amounts today to an Earth observatory is lack of funding and planning. Since 2002 the Earth science budget at NASA has been slashed 25 percent. In the next year, the number of operating sensors on NASA spacecraft will decrease by 40 percent over 2006 figures. Abdalati has urged a $500-million annual increase in funding for the Earth science budget.
"What the Bush administration did, they said let's go to Mars and let's forget about the Earth. A billion dollars was diverted from the Earth science budget and put into going to Mars and going back to the Moon. I mean it's crazy!" Tucker says, adding that he supports space exploration but would prefer that it didn't come at the expense of supporting satellite-studies of Earth.
The solution requires urgent planning, Tucker says. He agrees with other scientists who think that the U.S. must begin a series of talks with the European Commission and the European Space Agency as well as with counterparts in India, China and Japan to find a way to develop an international climate observing system.
Further, Tucker urges that copies of instruments should be built. "The incremental cost of the second or third copy are 15 percent of the cost of the first one," says Tucker, adding that one of the instruments originally built for Landsat 5 has been operating in orbit for 25 years and is the third of a three-unit production run. "It is not surprising the thing lasted so long. Successive copies are easier to build, and you make simple improvements so they last longer."
For now, all the money in the world will not get NASA out of its bind. Advance planning is needed to prevent repeating this dire trajectory.