Weather worse for Wed. launch

Illustration of GPS satellite.

Weather forecast not as good.

A 60 percent chance of favorable weather conditions exists on Wednesday for a Delta 2-GPS IIR-17 rocket carrying a Global Positioning Satellite. The launch window is between 8:23 and 8:38 a.m. EDT.

The forecast has worsened from a 70 percent chance of acceptable weather forecast on Sunday.

Clouds and rain have become more possible since a high pressure area began to weaken and move east. Scattered thunderstorms Wednesday afternoon will taper off by evening. Clouds and showers will be the concern.

Riding a Delta 2 rocket with nine strap-on solid rocket boosters, the satellite will enter an orbit 11,000 miles above the earth.

The GPS IIR-17(M) satellite, built by Lockheed Martin, will join the GPS constellation of 30 operational satellites. Features of the GPS IIR-M satellites include two new military signals for improved accuracy, enhanced encryption, anti-jamming capabilities, and a second civil signal to provide dual frequency capability and improve resistance to interference.

The GPS IIR-17 could be the 77th consecutive Delta 2 rocket to deliver its payload safely. In 130 Delta flights since 1989, 128 have been successful. The last failure was January 1997, when a Delta II rocket exploded shortly after launch from Cape Canaveral, due to a cracked solid rocket motor. At least 25 Delta 2 rockets are scheduled to fly during the next several years.

Look for live coverage Wednesday morning in The Flame Trench.

See details in the mission booklet.

FACTS ABOUT GPS:
-The first GPS satellite was launched in 1978.
-A full constellation of 24 satellites was achieved in 1994.
-Each satellite is built to last about 10 years.
-Replacements are constantly being built and launched into orbit.
-A GPS satellite is about 17 feet across with the solar panels extended.
-Transmitter power is only 50 watts or less.

GPS flight profile. Click to enlarge.
















Click below to see the map that shows the Eastern Range's Launch Hazard Area for the Wednesday launch.

For their safety, mariners are asked to remain clear of the LHA from 6:30 a.m. through 9:30 a.m.

Launch Hazard Area.