The Pegasus Rocket review will be held in Chandler, Arizona, April 3-4,
The SORCE Mission Operations Review will be held at LASP, Boulder, CO
April 23-24, 2001.
SORCE is planning a Science Team Meeting July 9, 10, 11 2001 at the
Laboratory for Atmospheric and Space Physics, University of Colorado,
SORCE scientists hope to present papers or attend the following summer
Workshop on the Evolving Sun and its Influence on Planetary Environments
June 2001 Granada, Spain.
International Solar Cycle Studies 2001-Solar Variability, Climate and
Spaceweather June 2001 Longmont, Colorado
IAGA Session on Solar Variability August 2001 Hanoi, Vietnam
March 2001 Project Summary
SORCE remains on schedule and within budget. No mission descopes are
required at this time. Late delivery of key spacecraft components has
resulted in build and testing schedule revision, and to date, there
has been no unfixable impact to the program, but instrument integration
slack has been depleted. Remanufacture of the spacecraft bench and late
delivery of Alenia transceiver have impacted the spacecraft schedule.
Additional testing facilities have been arranged at Ball Aerospace and
additional test equipment has been purchased by LASP to facilitate project
completion. A science support position has been offered as well. Dr.
Doug Rabin (GSFC Division 682) has been appointed Deputy Project Scientist
for SORCE. The SORCE ATBD will be resubmitted in March after revision
Mininum Science Criteria has been defined:
- Achieve orbit
and complete on-orbit check out for the SORCE spacecraft and instruments.
- Capture and
document daily values of Total
- Solar Irradiance
(TSI) and Spectral Solar Irradiance (SSI) for a duration of at least
18 months (>95% complete data record)
- Produce calibrated
and fully validated measurements of TSI with:
accuracy of 300 ppm (3s)
and long-term relative accuracy
of about 30 ppm/yr.
- Produce the
first spectral solar irradiance
dataset covering the complete solar spectrum, 120 to 2000 nm (~95%
of TSI), with:
determination of solar variablility
resolution and absolute accuracy suitable for use in Earth climate
TIM Shuttle Flight Science Objectives
- In conjunction with ESDIS, capture, archive
and distribute to the scientific community
the TSI and SSI data products.
- Show that 100 ppm (1s) accuracy can be achieved with an instrument
taken to space and returned for (re)characteriazation.
- Direct comparison of TIM and SOLCON
- Refine TIM characterization and operation
TIM is 90% complete with a few areas of work remaining. Kinematic mounts,
EMI filter brackets and adjustment and test of door mechanisms are mechanical
areas of continued work, and additional grounding is required in the electrical
area. Software learning curves have been overcome and progress is smooth.
Improved performance has been achieved in the ability to change program
parameters. There are diverse and ongoing housekeeping tasks to be done,
but overall progress on TIM is excellent. First light was seen on March
SIM is making rapid strides in flight build. SIM passed vacuum/pressure
test. The vacuum test was stopped at pressure of 1.1x10-6 torr. RGA analysis
showed most of the partial pressure was due to residual water vapor. SIM
held 1.2 atmospheres for 72 hours. SIM focal plane detectors are assembled,
tested and mounted in the flight case and alignment and focus are underway.
The flight drives for the Fèry Prism drive have been assembled
and characterized, and flight electronic boards are ready for fabrication.
The prism drive operation and photodiodes are completely under DSP control,
and lab spectra are being acquired. The mechanical fabrication of the
calibrator system is complete, and assembly is underway. The flight beamsplitter
has been delivered and the flight build of the periscope has begun. ESR
characterization is 75% complete, but the SIM ESR DSP code still needs
test. SIM slit width calibrations are complete, slit height is being analyzed
and slit throughput calibrations are underway.
SOLSTICE is 90% complete. Instrument mechanical, optical, grating drive,
and detector end-to-end testing is complete and instrument performance
meets or exceeds requirements on the bench! A hardware fringe counter
for the grating drive has been integrated into the DSP code and tested.
The grating drive will now keep position after any external disturbance.
Alignment stability tests are underway as well as preenvironmental test
tasks. The cover/bench rework is complete but still must undergo test.
Other loose ends such detector head noise quantitative assessment still
must be pursued. The SOLSTICE A unit went to SURF on March 26, was successfully