The 6:46 a.m. MT launch, lifting off from Vandenberg Air Force Base on California's coast, is the final mission of the medium-lift rocket that used to be the Centennial-based rocket manufacturer's work horse.
NASA kicked off its ICESat-2 mission to monitor our planet's ice sheets from space using a laser-scanning satellite this morning, with a launch that marked the end of a almost 30-year run for United Launch Alliance's Delta 2 rocket.
The launch of ICESat-2 marks the first time in almost a decade that NASA has had a tool in orbit to measure ice sheet surface elevation across the globe.
Image: A Delta II rocket carries the ICESat-2 into orbit.
A Delta 2 rocket lifted off September 15 carrying a NASA Earth science satellite on the final flight of a vehicle whose heritage dates back to the beginning of the Space Age.
The satellite's instrument, called the Advanced Topographic Laser Altimeter System, or Atlas, will also measure the heights of forests to determine the amount of vegetation in a region, as well as monitor other attributes of land surfaces, water and clouds.
"The precise and complete coverage afforded by ICESat-2 will enable researchers to track changes in land and sea ice with unparalleled detail, which will inform our understanding of what drives these changes", NASA said in a statement.
With more than a century of combined heritage, United Launch Alliance is the nation's most experienced and reliable launch service provider.
NASA has launched a climate satellite that will use lasers to measure changes in the Earth's ice sheets from space.
The early morning launch was visible as the rocket's exhaust plume was illuminated by the morning sun.
ICESat-2 will measure the height of our changing Earth, one laser pulse at a time, 10,000 laser pulses per second.
This is "one of the most fantastic machines we've ever launched into space", ICESat-2 program scientist Tom Wagner said in a statement.
"Three, two one, liftoff!" said a launch commentator on NASA television.
The laser on the satellite fires 10,000 times a second while travelling at a speed of 7km (4.3 miles) a second, from a height of 300 miles (482km). During its operational life, it also sent up the Kepler telescope, the twin lunar-orbiting GRAIL spacecraft, and a total of 48 Global Positioning System satellites. Four CubeSats accompanied the ICESat-2 into space.
Moving in an orbit that goes from pole to pole, ICESat-2 traverses 1,387 different orbital paths every 91 days.
Today's launch will be met by favorable weather conditions, the space agency announced yesterday, although the area's propensity for fog might hinder the locals' plans of watching the rocket blast off into space.