WEEKLY HIGHLIGHTS FOR WEEK ENDING 12 SEPTEMBER 2003:
GRAVITY PROBE B LAUNCH STATUS
- Late last week, NASA ordered Boeing to replace several solid booster rocket motors that were found to have unacceptable delaminations.
- This week, Boeing located replacements for the delaminated motors, and these replacements are currently en route to Vandenberg AFB.
- The GP-B launch, which had been scheduled for November 13, 2003, will be delayed for a short while. A new official launch date, expected to be early in December, will be announced soon by NASA.
- Conditioning of the dewar to a superfluid state is continuing. Conditioning is the process of taking liquid helium at a temperature of about 4 Kelvin to a colder state, known as superfluid, which will allow the helium to last throughout the duration of the mission. Getting the dewar 95% full of superfluid helium is a long, iterative process of repeated evacuations and fills.
- The dewar is currently 90.6% full of helium, at a temperature of 1.732 Kelvin. Over the coming week, the dewar will be filled to 95% capacity, with a corresponding temperature drop to 1.65 Kelvin.
- All space vehicle preparation activities at Vandenberg are proceeding on schedule, as planned.
Photo: The GP-B Cryo group performing a sub-atmospheric transfer of liquid helium into the dewar's main tank.