An advanced polar-orbiting weather observatory took a 1,600-mile roadtrip from Colorado to California this week, arriving at the satellite's Vandenberg Air Force Base launch site after the 40-hour journey.

The environmentally controlled transportation container holding the NPP satellite arrives outside the Astrotech payload processing facility at Vandenberg Air Force Base in California. Credit: 30th Space Communications Squadron/Doug Gruben

A crew of 16 people including team members from satellite-builder Ball Aerospace and NASA's project group escorted the spacecraft on the long-awaited shipment.

"It was a good trip, no incidents," said Scott Tennant, Ball's program manager. "The guys commented...one-lane construction zones are kind of an adventure when you have a wide payload."

Valued at $1.5 billion, the satellite's mission will continue global weather monitoring and climate data records while covering virtually the entire planet twice per day from its 512-mile-high polar orbit.

Its launch atop a Delta 2 rocket is scheduled for October 25 during a 9-minute window opening at 2:48 a.m. local time (5:48 a.m. EDT).

Originally named the NPOESS Preparatory Project, this satellite was supposed to be the testbed for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) that would combine the civilian and U.S. military weather spacecraft into a single program, an effort started by the Clinton Administration in 1994.

But the new system was beset by technical and money woes, ultimately leading to the cancellation of NPOESS last year.

That leaves this satellite -- which now goes only by the name "NPP" -- to become a true gapfiller in serving the needs of meteorologists over the next several years.

"It started off as more of pathfinder for the big NPOESS missions and has now taken on a little bit of an operational bend," said Tennant.

In the wake of the killing NPOESS and scrapping the idea of merging civilian and military satellite programs, the two are once again divided and developing their own next-generation systems.

Plans now call for a clone of NPP to be built and launched later this decade under the revised civilian satellite system.

An artist's concept of NPP in orbit. Credit: Ryan Zuber, Scientific Visualization Studio

Users of data from the polar-orbiting satellites are wide ranging. Meteorologists generate weather predictions, agricultural scientists need the information for drought management and monitoring vegetation and soil moisture and even the aviation community relies on the spacecraft to detect and track volcanic ash plumes for re-routing of aircraft.

NPP carries five instruments that provide imagery, atmospheric temperature and humidity profiles, and land and ocean surface temperature observations, all of which are key ingredients for weather forecasting. In addition, the satellite will measure ozone levels and reflected solar radiation from the planet.

Construction of NPP's core structure was completed in 2005. But waiting on its advanced instruments and a final clearance to fly forced an exceptionally long hold in the countdown to launch.

Weighing 4,700 pounds, NPP was tucked into a special transport container and finally shipped out of Ball's satellite factory on Sunday.

There's been celebrations on both ends of the trip.

"We had a big tailgate party when we left," said Tennant. "And the guys had a nice barbecue for us out here. It's been a very, very pleasant welcome. Overdue. Fantastic. Can't believe we're here."

Now inside the commercially-run Astrotech processing hangar on North Vandenberg, the satellite will undergo final confidence-building functional tests, removal of instrument covers and the loading of 800 pounds of maneuvering propellant before going to the launch pad on October 7.

The United Launch Alliance Delta 2 rocket has been stacked atop the SLC-2 West pad in preparation for blastoff. The two-stage launcher is equipped with nine strap-on solid-fuel boosters to haul the payload into orbit.

"We have 9 days of margin in our schedule between the time we finish with all of our operations prior to getting installed on the launch vehicle," said Scott Compton, NPP integration and test manager at Ball. "It's looking very good."

Once in space, NPP will unfurl its power-generating solar array and begin a three-month commissioning period before entering service, Tennant said.