Monthly Newsletter

January 2001

ESDIS has been officially signed off. The SORCE-ESDIS Interface Control Document draft has been submitted, and a final version will be submitted in the coming months. Earth science data type and data product short names have been submitted to DAAC for review and Level 4 (modeled 1nm irradiances) data product will be added to the interface control document for delivery to DAAC.
SORCE OASIS PS (operations and science instruments support planning and scheduling) is still ahead of schedule. A functional SORCE OASIS PS application exists and is capable of generating partial science plans. Generic planning capabilities are complete and tested as well as design and requirement of expert schedulers and constraint checkers. The Operations Concept Document is maturing in parallel with OASIS-PS development activities.

Mission Operations Status
Mission Operations are moving into high gear. An updated RF ICD has been received from GSFC and more comments are due 2/14/01. An initial draft of the PSLA has been received and the next draft release is 2/15/01. OASIS-CC development continues and is ready and for initial MU command testing. The computer security plan documents were sent to Goddard review the first week of February and evaluation meetings are scheduled at GSFC for the week of February 21, 2001. The first set of C and T Database Transfer files has been received from Orbital and ingested into the SORCE database.

Microprocessor Unit Status
The SSI (standard serialized interface) command for the FPGA (field programmable gate array) has been partially completed and delivered for software test. The final design should be released to software testing by February 23, 2001. The SSI telemetry FPGA design is in process and should be delivered to software test by March 16, 2001. The MU power distribution board engineering model has been delayed but work is progressing and full integration into the engineering model is expected by the end of February 2001. The flight unit parts are in house and flight testing should be complete by March 15, 2001. The GCI (generic channel interface) engineering model boards are complete and tested. Flight board fabrication has begun.
Flight Software PCIIO hardware integration is underway, 1553 communications are on flight hardware, and the instrument commands and telemetry will follow. The GCI software

driver is complete and ready for test. The inflight patch mechanism design is on the SORCE website for review. The implementation of command/telemetry items has begun.

Digital Signal Processor Status
The DSP (digital signal processor) SOLSTICE grating drive control is fully functional. The PID (proportional integral derivative) is being fined tuned for operational agility and robustness. The DSP (digital signal processor) code has been fully tested. The interface between the FPD (Fery prism drive) and the DSP board is working on SIM.

Spacecraft Systems
Spacecraft system progress is good. The MICD, (mechanical interface control document), required for fairing fabrication, has been signed. Payload handling, site facilities and processes, and hydrocarbon monitoring at storage and hot pad facilities have been reviewed. An integrated thermal model of the spacecraft bus and the SORCE instruments is in process, as well as the operational constraint analysis. The routing and stuffing of the SORCE instrument module harness is underway at Orbital and LASP. Power, mass, bandwidth and memory budgets have adequate margins.

Orbital News
Developments from Orbital on the spacecraft bus follow. The CEU EDU (Central Electronics Unit Engineering Development Unit) was delivered to flatsat and test is being repeated on the CEU EDU. This test had been previously run on GALEX hardware. The battery CPV's have been bought off and the APE EDU (attitude power electronics engineering development unit) has completed test. The bus harness mockup is complete and the preliminary CDR transceiver material was reviewed Feb. 7, 8, 2001. Avionics production delays are starting to require work-arounds in order to meet schedule. The EDU fine sun sensor head failed shock test. A redesign is in work. A GALEX (Galaxy Evolution Explorer) battery is not available to SORCE and other options are being researched. PRE (power regulator electronics) evaluation is still ongoing per NASA request.

Information Submission:
Each month SNS will present mission progress, highlights, and news. If you have any information to distribute to the SORCE Team, contact, and we will include it in the next month's issue of SNS.

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