The successful launch of a U.S. government weather satellite May 24 will put improved capabilities into the hands of forecasters, and also marks the return to flight of Boeing Co.’s Delta 4 rocket after a 17-month hiatus.

The Geostationary Operational Environmental Satellite (GOES) N is the first of a new series of U.S. weather sentinels and represents an incremental improvement over the two now overlooking the East and West coasts of the United States. It is expected to be pressed into service between 2008 and 2011 and until then will serve as an on-orbit spare, said Steve Kirkner, GOES program manager at the National Oceanic and Atmospheric Administration (NOAA).

GOES N is the first of three geostationary weather satellites built by Boeing Satellite Systems International of El Segundo, Calif. The satellites in service today are the last of five built by Space Systems/Loral of Palo Alto, Calif.

A new generation of GOES satellites now under study, dubbed GOES R, is expected to provide a dramatic leap in capability starting early next decade, Kirkner said in a May 23 interview.

GOES N was scheduled to launch in May 2005, but was delayed repeatedly by a variety of issues, including technical concerns and a labor dispute that for a time grounded Boeing’s entire Delta rocket fleet. The launch was delayed further to get past the eclipse, which roughly corresponds to the vernal equinox and autumnal equinox, during which a satellite’s solar arrays cannot draw maximum energy from the Sun.

The GOES N mission was the first for the Delta 4 rocket since the heavy-lift member of the family failed to deliver a dummy payload to a sustainable orbit in a December 2004 demonstration . The next Delta 4 launch, scheduled for June, will loft a classified satellite for the National Reconnaissance Office , according to Douglas Shores, a Boeing spokesman.

The GOES N series of satellites also includes GOES O and GOES P, which are scheduled to launch in April 2008 and October 2009, respectively, Kirkner said.

GOES O is finished and in storage , according to Mark Spiwak, GOES program director at Boeing Satellite Systems. GOES P is undergoing thermal vacuum testing and is expected to be placed in storage in late summer or early fall, he said.

Steve Letro, a meteorologist in charge at the U.S. National Weather Service’s forecast office in Jacksonville, Fla., said the current GOES satellites have been performing well, and have played a key role in predicting severe storms like Hurricane Katrina.

However, Hurricane Katrina’s death toll of roughly 1,300 indicates there is significant room for improvement in forecasting, Letro said. While meteorologists likely will have a significant waiting period before they can take advantage of the improvements offered by GOES N, having a spare on orbit to ensure coverage in the event of a satellite failure is helpful , he said.

One of the GOES N improvements that meteorologists are most looking forward to — aside from the slightly more accurate measurements to be taken by its main sensors — is new batteries that should enable the satellite to operate even when its solar arrays are blocked during an eclipse, Letro said.

The GOES N satellite also includes the first operational version of the Solar X-Ray Imager, Kirkner said. That instrument, built by Lockheed Martin Space Systems Advanced Technology Laboratory in Palo Alto, Calif., is intended to monitor the Sun for conditions and events like solar flares that can disrupt satellite operations and cause problems for electrical power grids on Earth, according to a company news release.

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