NASA’s new spacecraft to sniff carbon dioxide in the earth’s atmosphere reached orbit on Wednesday after launching from Vandenberg Air Force Base in California.
The $468 million Orbiting Carbon Observatory-2 mission had to be put off when Tuesday’s launching attempt was halted with just 46 seconds left in the countdown. Technicians spent the day replacing a defective valve in the system that sprays water beneath the rocket during liftoff.
The Delta 2 rocket carrying the satellite lifted off at 5:56 a.m. Eastern time on Wednesday and rose to 429 miles above earth. The success comes five years after the loss of the mission’s original satellite: its clamshell nose cone failed to separate, and the spacecraft splashed into the ocean off Antarctica. At the end of 2009, the Obama administration gave the go-ahead to build a replacement.
Over the next 10 days, flight controllers will check out the spacecraft, and will then nudge it over three weeks into its final destination, 438 miles up in an orbit passing over the North and South Poles, where it will take its position at the front of a parade of other earth-observing spacecraft. The mission is to last at least two years.
The observatory carries a single instrument, which will measure carbon dioxide levels by looking at the intensity of colors of sunlight bouncing off the earth (carbon dioxide absorbs certain colors, but not others).
The burning of fossil fuels and other human activities releases on average 100 million tons of carbon dioxide a day in the air, and the pace of emissions continues to speed up. The atmosphere’s levels of carbon dioxide, which traps heat and contributes to warming temperatures, recently reached 400 parts per million, up 40 percent since the start of the Industrial Revolution.
The observatory will make a million measurements a day, although interference by clouds means that perhaps only 10 percent will turn out to be useful. That will still provide a bounty of data for scientists looking to gain a clearer picture of what happens to the carbon dioxide, only half of which stays up in the air. A quarter of the emissions is absorbed by the oceans; another quarter is believed to be taken up by plants growing on land, but scientists do not have detailed data to see exactly where. The patterns also change with the seasons and can be affected by floods and droughts.
“There’s something really neat going on,” said David Crisp, the head of the mission’s science team. “We just need to find it.”
The Orbiting Carbon Observatory-2 is the second of five launchings this year for earth science missions as NASA replenishes its aging fleet. Before Wednesday’s launching, the space agency had 16 spacecraft to observe the earth from orbit; 13 of them are beyond their designed lifetimes.
“This year and indeed the rest of the decade will be extremely busy times as we bring to culmination many years of effort to reinvigorate the space-based component of our earth-based observations,” said Michael Freilich, director of NASA’s earth science division.