# Presentation: 353485

## RHESSI RECEIVING REVIEW

**Notes:**
Intro agenda page 1

## RHESSI RECEIVING REVIEW

**Notes:**
Intro agenda page 2

## RHESSI RECEIVING REVIEW

**Notes:**
Intro agenda page 3.

## RHESSI Receiving Review

**Mission Overview**
- Dr. Robert P. Lin
- Principal Investigator
- University of California at Berkeley

## Slide 5

## Slide 6

**Notes:**
Brian Dennis 2. 

## Slide 7

**Notes:**
Brian Dennis, page 3.

## Slide 8

**Notes:**
Brian Dennis, page 4

## Slide 9

**Notes:**
Brian Dennis, page 5

## Imager – side view

- Imager – Side View

## Mechanical Cryocooler

## Slide 15

## Slide 16

**Notes:**
Brian Dennis, page 12

**Notes:**
13.

**Notes:**
14.

## Slide 19

**Notes:**
15. feb20_1106_lightcurves

## Slide 20

**Notes:**
16. feb20_1106_cleaned_maps

## Slide 21

**Notes:**
Page 17.

## Slide 22

**Notes:**
Sam Krucker, Page 18.

## Slide 23

**Notes:**
Sam Krucker, Page 19

## Slide 24

**Notes:**
Sam Krucker, Page 20

## Slide 25

**Notes:**
Page 21

## Slide 26

**Notes:**
Page 22

## Slide 27

**Notes:**
Page 23

## Slide 28

**Notes:**
24.

## Slide 29

**Notes:**
Page 25

## RHESSI Receiving Review

**Mission Status**
- Dr. Manfred Bester
- Project Manager
- University of California at Berkeley

## Mission Requirements

| Mission Element | Requirement |
| --- | --- |
| Launch Vehicle | Adequate capability to achieve mission orbit |
| Orbit | 600 x 600 km at 38 deg
Minimize radiation damage, maximize life time and ground station coverage |
| Launch Date | Mid 2000 to end of 2001, near solar maximum |
| Mission Life Time | 2 years nominal, 3 years desired to capture sufficient solar events to perform analysis |
| Data Volume | 16 Gbits storage, 8 Gbits/day downlink |
| Ground Station | Meet telemetry and command requirements, simplify operations and reduce costs |
| Attitude | Sun pointed to 0.2 deg such that entire solar disk is within instrument FOV |
| Spin Rate | 12-20 RPM, required by imaging sample rate |

**Notes:**
Intro agenda page 1

## Spacecraft Systems

- Spacecraft Bus (Spectrum Astro)
- Spin Stabilized Sun Pointed Platform
- ACS Comprises Coarse and Fine Sun Sensors, Magnetometer and 3 Torquer Rods
- 4 Solar Panels, 11 NiH2 15 A-hr CPVs
- S-Band Transceiver, 4 Antennas
- Instruments
- Imager Including SAS, RAS, ADP (PSI)
- Spectrometer, IDPU, PMT-RAS, PD (UCB)

## Ground Systems Design

## U.C. Berkeley Mission Operations Center

- BGS Antenna, Equipment Racks and FOT Workstations at the UCB Mission Operations Center

## IT Network Security

- Revised IT Network Security Plan Submitted to GSFC
- Covers Joint RHESSI and FAST Operations
- Enhanced Security Features in MOC Include:
- Cardkey Entry System
- Access to MOC Controlled by U.C. Police Department
- Alarm System Tied into U.C.P.D.
- Access Restricted to Personnel Essential for Flight and Ground Station Operations
- Video Surveillance Systems

## Launch and Ascent to Orbit

- Drop Time: 05-Feb-2002  20:58:10.665 UTC

## Mission Orbit

- Target Orbit:
- 			600.00 x 600.00 km at 38.00 deg
- Orbit at Payload Separation:
- 			600.24 x 586.85 km at 38.02 deg
- Orbit at L+90:
- 			603.51 x 578.13 km at 38.03 deg

## Ground Station Coverage

## Mission Status

- Launch & Orbit Insertion Including Sun Pointing Nominal
- First Acquisition at Berkeley Successful
- Spacecraft Bus Nominal (Power, ACS, C&DH, Flight Software, Thermal, Telecomm)
- Instrument Turn On Nominal
- Cryocooler Now Running at 52 W
- First Flare Observed at L+7 Days
- Spacecraft Fully Autonomous at ~ L+50 Days

## Science and Engineering Data Recovery

| Ground Station | BGS | WLP | WHM | AGO |
| --- | --- | --- | --- | --- |
| Passes to Date | 526 | 302 | 100 | 43 |

- Total Access Time Until L+90:	> 8,400 min
- Mission Data Recovery:		> 98%
- Mission Requirement:		8.0 Gbits/day
- Mission Achievement at L+90:	1.5 Tbits (16.7 Gbits/day)

## Phase E Organization

## Sustained Engineering & Maintenance

| Organization | Responsibilities in Phase A-D | Support in Phase E |
| --- | --- | --- |
| U.C. Berkeley | Project Management
Spectrometer & Instrument Data Processor 
Spacecraft Integration and Test
Berkeley Ground Station, MOC/SOC Development
Mission Operations, Flight Dynamics & Data Analysis | Sustained Engineering Support
(UCB Engineering Team)
GDS, MOC & SOC Systems
(UCB Operations Team)
EMP Systems (R. d’Angelo) |
| NASA / GSFC | Grid Mounts, Grid Characterization
Cryogenics Design, Flight Cryocooler, Instrument Blankets
I&T Hardware and Software Support (ITOS, Imaging)
Data Analysis Software, Data Analysis and Archiving  | Data Analysis
(B. Dennis)
ITOS Software
(G. Greer) |
| Paul Scherrer Institute | Imaging Telescope, Solar Aspect and Roll Angle Systems
Aspect Data Processor  | SAS, RAS &  ADP Support
(M. Fivian) |
| Spectrum Astro | Spacecraft Bus
I&T and L&EO Support to UCB  | S/C Bus, Hot Bench & Flight Software (R. Wanner) |
| SpaceWorks | Spacecraft Support | N/A |
| NASA / KSC | Launch Vehicle Contract  | N/A |
| Orbital Sciences Corporation | Launch Vehicle  | N/A |

## Problems & Resolutions

- Anomaly Detection
- Operations Personnel on Console
- Paging of Operators via SERS
- Anomaly Resolution
- Assessment by FOT, Mission Operations Manager, Mission Operations Scientist
- Quick Interaction with Subsystems Engineers, Instrument Scientists and PI
- Anomaly Resolution According to Contingency Plan

## Budget & Physical Constraints

- RHESSI Team Awaits Approval of Phase E Budget
- Updated IT Network Security Plan Has Been Submitted
- External Supports
- PSLA for NASA GN Support at Wallops Ground Station
- MOU for Pass Supports at Weilheim Ground Station
- Expected Mission Life Time
- At Least 3 Years
- Cryocooler Performance Much Better Than Anticipated
- Detectors Are Twice as Sensitive as Anticipated
- Time at Which Minimum Science Will Be Reached Depends on Solar Activity

## RHESSI Receiving Review

**Mission Operations**
- Mark Lewis
- Mission Operations Manager
- University of California at Berkeley

## Launch and Early Orbit Checkout

- RHESSI Launched on February 5, 2002 at 20:58 UTC
- Launch resulted in nominal orbit insertion
- ~600 km circular orbit, 38 degree inclination
- L&EO Operations conducted with Spectrum Astro support
- First RHESSI contact on orbit came at 22:40 UTC
- BGS locked onto telemetry without difficulty
- Spacecraft was healthy, power positive, with arrays deployed
- Spacecraft pointing was within 10 degrees of the sun
- All temperatures were nominal
- Commanding attempts were successful

## Launch and Early Orbit Checkout

- Major Milestones Accomplished During First Week
- Set spacecraft clock
- Loaded Automatic Time Sequence  (ATS) command load
- Tested all downlink rates (125k, 1M and 4M)
- Powered on the IDPU
- Turned on the cryocooler; ramped power to 76W; then down to 40W
- Turned on Particle Detector
- Powered SSR; Partitioned SSR; Began recording data
- Turned on Imager;  Collected high rate imager data
- Powered Germanium Detectors; ramped to full power
- Spun spacecraft to 14 RPM and balanced

## Launch and Early Orbit

- Additional Milestones Since Launch
- RHESSI captured its first flare on February 12, 2002
- Spun up to 15 RPM and balanced
- Tuned Particle Detector SAA detection algorithm
- Exercised attenuators; initiated autonomous shutter control
- Tuned thresholds for all 9 GEDs
- RHESSI captures first X-class flare on April 21, 2002
- FOT recovered from CPU reset in just 2 orbits (~3 hours)
- RHESSI never stopped taking data

## Normal Operations

- Highly Autonomous Operations Planned for RHESSI
- 6 BGS passes per day are currently staffed
- 3-5 Wallops per day are not staffed
- Weilheim passes requested during times of high solar activity
- Only post-pass data available
- BGS passes will eventually be unstaffed
- All passes will be monitored by VMOCC/SERS
- Violations of limits or configmon rules result in paging FOT
- ATS loads currently cover 48 hour period
- FOT analyze spacecraft trend plots
- Ops Manager present during any unusual commanding

## Mission Planning

- Scheduling of Pass Supports
- SatTrack produces view periods and link margins
- BGS passes scheduled directly from SatTrack products
- Desired Wallops passes sent to Wallops for scheduling
- Weilheim passes requested on a best effort basis
- Schedule from Wallops and Weilheim merged with BGS passes
- SSR Memory Management
- High magnetic latitude decimation during orbital night
- Particle storms can fill SSR at 1% per minute
- Decimation times manually inserted into loads
- Next version of SatTrack will include high magnetic latitude zones

## Configuration Control

- All RHESSI GSE is Under Configuration Control
- Changes to GSE hardware/software require CCB approval
- Changes to Ops Workspace tested on the open network
- Software configurations controlled using SCCS
- If a problem arises, configuration can easily be rolled back
- Configuration Control Board
- The CCB includes Mission Ops Manager, Mission Ops Scientist, Science Ops Manager, Network Administrator and the Mission Director (at GSFC)

## Spacecraft Simulator

- The RHESSI Spacecraft Simulator, aka The Hotbench
- Located at SSL
- Assembled by Spectrum Astro
- Includes CPU, IDPU, SSR and simulation of some hardware
- ITOS used to for command and control, through dedicated PTP
- Allows for loading and testing of Flight Software (IDPU also)
- Includes AC1000 to simulate ACS sensor inputs and orbit
- Limited hardware modeling (ie no temp sensors, etc)
- Any change to Flight software is first tested on Hotbench
- Currently being used to test off-pointing patch
- Used to test new RTSs
- Hotbench is used for training exercises

## Flight Operations Team

- FOT Staffing and Experience
- Mission Operations Manager
- Mark Lewis – EUVE, FAST, RHESSI (10 years)
- Spacecraft Controller/Programmer
- Joseph Rauch-Leiba – FAST, RHESSI (5 years)
- 2 Spacecraft Controllers/Mission Planners
- Jeremy Thorsness – EUVE, RHESSI  (5 years)
- Pam Lehr – FAST, RHESSI (3 years)
- Pam is leaving in August; will not be replaced
- 1 Backup Spacecraft Controller (FAST Controller)
- Marty Eckert – EUVE, FAST, RHESSI (10 years)

## Flight Operations Team

- FOT Responsibilities
- Health and safety of the spacecraft is prime responsibility
- Currently, all 6 BGS passes per day are staffed by at least one spacecraft controller
- Wallops and Weilheim passes are taken as unstaffed autonomous
- BGS passes will be unstaffed once limits are tuned better and spacecraft behavior is well understood
- VMOCC/SERS is used to autonomously monitor health and status
- VMOCC/SERS monitors vc0 and vc1 from all contacts
- If an anomaly is detected, a page and email is sent out to FOT
- Paging is persistent and will continue until problem file is handled

## Flight Operations Team

- FOT Responsibilities – cont.
- Produce Automatic Time Sequence (ATS) loads
- Merge SatTrack products and contact schedules in CMS
- Produce ATS load; manually edit load as necessary
- Check load twice (different people)
- Load ATS to spacecraft every other day
- Dump vc1 data during BGS contacts
- Adjust attenuator states as necessary
- Produce and monitor spacecraft trend data

## Trend Analysis

- Daily Trend Plots
- Plots of important systems are plotted daily using IDL
- Plots are available on the web
- _[http://sprg/~hessiops/state-of-health/welcome.html](http://sprg/~hessiops/state-of-health/welcome.html)_
- Long-Term Trend Plots
- Currently produced manually by FOT
- Produced for investigations, or as requested by team
- Automated solution is in development
- Plots will be put on web once automated

## Contingency Operations

- Anomalies May be Detected in Real-time or by VMOCC/SERS
- Spacecraft Controller on-shift/on-call evaluates severity of anomaly
- Two-way alpha-numeric pager provides information on rules violated
- Controller can access problem report remotely
- Controller can view most relevant spacecraft data from last BGS pass
- _[http://hessi.ssl.berkeley.edu/ground_systems/hessi_spacecraft_status.html](http://hessi.ssl.berkeley.edu/ground_systems/hessi_spacecraft_status.html)_
- Controller Notifies Ops Manager
- Instrument specialists or spacecraft engineers called in as necessary
- Mission Director notified in a timely manner

## Contingency Operations

- Anomaly Resolution
- Spacecraft Controllers are trained and authorized to respond immediately to anomalies when necessary
- With short passes, controllers must be ready to safe the spacecraft quickly, before seeking outside authorization
- Anytime the spacecraft is not in immediate danger, Ops Manager will be contacted before proceeding
- Ops Manager should be present during anomaly recovery
- New contingency procedures developed and implemented with system experts, on as needed basis
- Lessons learned used to update existing contingency procedures
- Anomalies and resolution reported in updates to RHESSI team and in weekly report to Mission Director

## Operations Summary

- L&EO Went Smoothly
- RHESSI is performing great
- Many activities were finished ahead of schedule
- Instruments were on and taking data after one week
- Spacecraft was fully checked out after six weeks
- Moving Towards One Shift Operation
- Most routine functions have already been automated
- Autonomous monitoring elements are in place
- Fine tuning of rule base nearly complete

## RHESSI Receiving Review

**Instrument Status - Spectrometer**
- Dr. David Smith
- Spectrometer Scientist
- University of California at Berkeley

## Slide 61

**Notes:**
David Smith, page 2

## Slide 62

**Notes:**
David Smith, page 1

## RHESSI Receiving Review

**Instrument Status - Imager**
- Dr. Gordon Hurford
- Imager Scientist
- University of California at Berkeley

## IMAGING SYSTEM CHARACTERISTICS / STATUS

**Imaging principles**
- Uses a set of 9 rotating modulation collimators.
- Each grid pair rapidly time-modulates the incident x-ray flux..
- Data system records arrival time and energy of each detected photon.
- Analysis software uses list of detected photons to reconstruct image of the source.
- Requires good aspect solution and knowledge of grid parameters.
**Imaging characteristics**
- Well-suited to relatively simple source geometries. (‘TRACE-like’ images are not expected.)
- Inherently accurate absolute source locations (~1 arcsec)
- Technique is inherently ‘robust’. (Depends on **knowledge** rather than **control** of instrument parameters.)**	**
**Imaging system and software are performing well.**
- System is yielding science-quality images with photometry that supports imaging spectroscopy.

**Notes:**
Gordon Hurford, page 1

## RHESSI IMAGING – SOLAR ASPECT SYSTEM (SAS)

**Successfully providing pitch and yaw aspect for image reconstruction. **
**Internal consistency checks agree to better than the 0.4 arcsec rms requirement.**
**Good prospects for stand-alone limb science (e.g. helioseismology).**
**Post-sunrise spacecraft dynamics briefly move Sun outside SAS ‘6-limb’ field of view, resulting in reduction in aspect accuracy for 1 or 2 minutes after ‘sunrise’.**
- Analysis software upgrade will compensate for this.
**Gradual loss of sensitivity (8.3% per month)**
- x200 sensitivity margin
- Exponential model  lifetime greater than 5 years

**Notes:**
Gordon Hurford, page 2

## RHESSI IMAGING – ROLL  ASPECT SYSTEM (RAS)

**Side-looking CCD-based star scanner to provide roll aspect data**
**Fully operational, but interaction of earth albedo and current anti-blooming provision results in orbit-dependent mid-day data gap of 0 to 10 minutes.**
**Revised parameterization should improve this.**
**Because of manpower limitations, current workaround uses PMTRAS for roll aspect.**** **

**Notes:**
Gordon Hurford, page 3

## RHESSI IMAGING  -  ROLL ASPECT FROM PMTRAS

**Side-looking PMT-based star scanner provides roll aspect.**
**Added as a backup because of subsequently-resolved RAS scheduling concerns during phase C/D.**
**Currently providing roll aspect which meets 1-arcminute rms requirement**
**PMTRAS analysis software is not yet fully transparent to user. **
- 	Sometimes requires manual override of star identification.

**Notes:**
Gordon Hurford, page 4

## IMAGING SYSTEM ISSUES 

**Detector 2 threshold**
- ~10 percent loss of overall effective area below 20 keV
- Introduces uncertainty in source sizes measurements in range 2.5 to 3.5 arcsec below 20 keV.
- Future exploitation of harmonics may compensate for this
- Some reduction in dynamic range of high resolution images
**Data gaps**
- Software compensation to minimize impact on imaging is in place.
- ~10 percent loss of sensitivity in typical applications
**Roll aspect solution not yet fully automated**
- Manual workaround is in place.
- Algorithm improvements are in progress.
**Grid phase calibrations not yet complete.**
- Preliminary phase calibrations in place for grids 3 through 9. (6.8 arcsec resolution)
- Phase calibration for grids 1 and 2 are in progress. 	      (2.3 arcsec resolution)

**Notes:**
Gordon Hurford, page 5

## IMAGER SELF-CALIBRATION 

- Achievement of high dynamic range images depends on good knowledge of grid transmission and modulation efficiency.
- Pre-launch calibrations of grids were self-consistent  to 2% level.
- Inherent redundancy enables the transmission and modulation parameters to be refined using post launch data.
- Improved parameters and algorithms can be applied retroactively to complete RHESSI database.

**Notes:**
Gordon Hurford, page 6

## RHESSI Receiving Review

**Science Operations**
- Tim Quinn
- Science Operations Manager
- University of California at Berkeley

## Science Operations

**Level Zero Processing**
- HESSI Science Operations are fully autonomous
- Ground Station contact files (VC0-VC3) are transferred to SUN Enterprise Server post pass
- UNIX shell scripts call IDL routines which perform level zero processing
- Convert contact files (VC1-VC3) to FITS files
- Produce QUICKLOOK data and append to FITS files
- Count Rates, Packet Rates, and Flare List
- Update HESSI database
- Produce count rate plots accessible from **rhessidatacenter.ssl.berkeley.edu**

**Notes:**
Tim Quinn

## Science Operations

- Data Archiving
- All Level Zero Products are archived on RAID system
- Raw data files (VC1-VC3) are also archived on RAID system as well as CD-R

**Notes:**
Tim Quinn

## RHESSI Receiving Review

**Science Data Analysis**
- Dr. Gordon Hurford
- Imager Scientist
- and
- Dr. Jim McTiernan
- SOC Scientist
- University of California at Berkeley

## RHESSI DATA ANALYSIS PRINCIPLES 

**PI team and community have equal access to the data and analysis tools.**
**Significant effort to make user-friendly interface.**
**Provision for convenient comparison with other ground and space-based data sets.**
**Science-driven tradeoffs, which most missions make before the fact.**
- Time resolution
- Energy range and resolution
- Spatial resolution
- Image field of view
**Key RHESSI strategy is to defer these tradeoffs to data analysis phase.**
- RHESSI data contains time- and energy-tagged photons
- Tradeoffs can be made in response to nature of the flare and scientific objectives.

**Notes:**
Gordon Hurford RHESSI Data Analysis, page 1

## RHESSI DATA PRODUCTS 

**Basic data product classes   (User-selected time, energy and spatial parameters)**
- Light curves
- Images
- Integrated energy spectra
**Advanced data product classes**
- Feature-based spectra
- Feature-based light curves
**Quick look products are appended to Level-0 database.**
- light curves with 4s time resolution, 8 energy bands
- representative flare images (limited quality)
- representative integrated spectra
- flare lists
- observing parameters, etc
**Most science analyses start from level-0 data**.

**Notes:**
Gordon Hurford RHESSI Data Analysis, page 2

## RHESSI DATA ANALYSIS STATUS 

**Documented and functional analysis software is on-line and distributed via GSFC Solar Software.**
- Upgrades and improvements continue to be made.
**Level-0 database**
- Created at SSL with no routine operator intervention.
- Opened for general use on March 20.
- Local access at SSL
- Mirrored for community access at GSFC and ETH (Zurich)
- Populated with less than 1 day latency
- Most quick look products are available.
- Some reprocessing (~30%) has been necessary.
- Flare locations and quick-look images to be added when aspect issues resolved.

**Notes:**
Gordon Hurford RHESSI Data Analysis, page 3

## RHESSI DATA ANALYSIS STATUS

**HESSI Experimental Data Center is on-line.**
- Access to Level-0 database
- Web-based access to analysis tools
- _[http://HEDC.ethz.ch/](http://hedc.ethz.ch/)_
**Documentation and details at **
**RHESSI SOFTWARE AND DATA ANALYSIS CENTER**
- _[http://hesperia.gsfc.nasa.gov/rhessidatacenter/](http://hesperia.gsfc.nasa.gov/rhessidatacenter/)_

**Notes:**
Gordon Hurford RHESSI Data Analysis, page 3 continued

## RHESSI Receiving Review

**Education & Public Outreach**
- Dr. Nahide Craig
- EPO Scientist
- University of California at Berkeley

## RHESSI EPO at Berkeley

**Accomplishments**
- RHESSI Lithograph
- RHESSI LAUNCH Day
- Chabot Science Center
- SSL - TV Media Coverage
-  _[Science@NASA](mailto:Science@NASA)__ on HESSI_
- NASA Connect “Having a Solar Blast”  Video
- Released to 120,000 Educators
- RHESSI EPO as a
- 	Model for LWS EPO

**         ****Phase E Plans**
- NOBCChE Invited Teacher
- 	Professional Workshop-March 2002
- NSTA Conference April 2002
- 2000 HESSI Lithos Distributed
- CAL Day OPEN HOUSE April 2002
- Lecture & Guided Tour of MOC
- RHESSI Booth at Campus
- Lecture at Physics Dept
- Dissemination of Materials
- Summer Teacher Workshops
- Best of Eclipse Video
- Partnerships with SEC Forum and Science Museums & Live Web broadcast from location

**Notes:**
Nahide Craig