JWST Science Operations
from the perspective of a GO/GTO
Alex Fullerton*
Webb Instrument Team
TIPS/JIM
20 March 2008
* who ripped off some of the slides from Jeff Valenti
Ground Segment Operations
JWST
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
JPL Deep Space
Network
S-Band
Ka-Band
Astronomers
Grant
Solicitation
Phase 1
Phase 1
Solicitation
Science Data
Notification
Acceptance
Proposal
Selection
Phase 2
Constraints
Phase 2
Preparation
Calibration
Proposals
Status
Grant
Long Range
Planning
Grants
Management
Notification
Short Term
Scheduling
Obs. Plan
Generation
Science Operations
Flight Operations
Wavefront
Control
Engineering
Proposals
Orbit
Maintenance
DSN
Scheduling
FSW & Script
Loads
Sci Data
Calibration
Calibration
Ref. Data
• Command &
Data Uplink
Wavefront
Monitoring
• Recorded
Data Downlink
• Health &
Safety
Monitoring
• Clock
Correlation
Mission
Scheduling
FSW & Script
Maintenance
Real-Time
Operations
Sci Data
Archive
Orbit
Determination
Eng Data
Archive
Eng Data
Trending
• Ranging
• Simulator
Operations
FSW & Script
Dumps
FSW & Script
Maintenance
What Does a GO/GTO Care About?
1)
Writing Proposals and Planning Programs
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•
2)
Integrated Proposal Planning Tool
Documentation
Analyzing Data
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“Pipeline Processed”; on-the-fly recal (+ ability to tinker?)
Long-term, stable but refreshed data archive(s)
Meta-data and documentation
3)
Writing Papers
4)
Funding
5)
Schedules
PERFORMING INNOVATIVE RESEARCH
What Do We Care About?
1)
Writing Proposals and Planning Programs
•
•
2)
Integrated Proposal Planning Tool
Documentation
Analyzing Data
•
•
•
“Pipeline Processed”; on-the-fly recal (+ ability to tinker?)
Long-term, stable but refreshed data archive(s)
Meta-data and documentation
3)
Writing Papers
4)
Funding
5)
Schedules
ENABLING INNOVATIVE RESEARCH
Proposals and Obs Planning
DD Proposals Anytime
Proposer
GO Proposals
Cycle Boundary
PI uses ETC
To Determine
Amount of
Time Needed
PI uses APT
To Prepare
Science
Proposal
Peer Review
Of Science
Proposals
(~1400)
STScI
Director
Review
& Approval
Preparing Science Proposal for Science Review
PI Gets
Time on the
Observatory
YEAH!
GO
Programs
GO/Calib/Eng
Programs
Grant
Process
Begins
PI uses ETC
To Prepare
Observations
For Flight
STScI
Staff
Proposer
Programs Change During the Cycle
Guide Stars
Proposal
Constraint
Generator
Long Range
Short Term
APT used to
Planning
Scheduling
Develop
Sci/Cal/Eng
Program
Planning & Scheduling the Observations
The [???] Tool
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APT: Astronomer’s Proposal Tool
APT: Advanced Planning Tool
PPT: Proposal Planning Tool
PDT: Proposal Definition Tool
IPT: Integrated Planning Tool
The [TBN] Tool (T3)
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Exposure time calculators
Proposal editor
Target visualization
Overhead calculator
Schedulability tool (field of regard, guide stars, …)
Mosaic planner
Microshutter Array (MSA) planning tool for MOS
The MIRI Imaging Template
(K. Gordon & S. Friedman)
Input
A. Source Specification:
Details
Remarks
Input via generic form
B. Instrument Configuration:
Detector
Filters
Specify readout region
Choose from menu
Specify readout pattern
Choose from menu
Specify filters
Choose from menu
For each filter:
Specify NINT (number of ramps)
[per dither step]
C. Observation Implementation:
Dither? [Y/N]
If “Y”
Select dither pattern
Mosaic? [Y/N]
If “Y”
Specify tiling pattern via generic form
Special Requirements?
If “Y”
Specify via generic form
Choose from menu
Choose from menu
GUI Input to a Template
Exposure Time Calculators
ETC Interfaces
FGS Acquisition
NIRCam Imaging
NIRCam
Coronagraphy
NIRSpec Acquisition
NIRSpec
Spectroscopy
MIRI Imaging
MIRI Spectroscopy
MIRI Coronography
TFI Imaging
TFI Coronography
Common
infrastructure
Visualizer / Mosaic Planner
Schedulability Tool
Examine constraints and their consequences:
• Target visibility window(s)
• Field of Regard
• Sun/Earth/Moon avoidance
• Availability of Guide Stars
• ORIENTATION
• Special Requirements
• Phase-critical windows
Ability to iterate … to explore the consequences of specific
observing strategies or choices.
JWST Field of Regard
Visibility Window Durations
Orient Constraints
Overhead Calculator
Total wall-clock time required for an observation:
• total integration time
• time for SI set-up, mechanism movements
• time for dithers
• time to tile a mosaic
• time to slew to the field initially
Ability to iterate … to explore the consequences
of specific observing strategies or choices
Overheads Will Include a Slew Tax
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JWST slews slowly
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Scheduling constraints impact slew optimization
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Reaction wheels are not that massive
Slew 90 degrees in about an hour
Slew must stay in field-of-regard
Pointing, orient, and timing constraints
Nonuniform target distribution on the sky
Links between visits
Proposals and allocations must include overhead
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JWST is very sensitive (even short exposures yield science)
Measure program cost fairly
Include average slew time in overhead estimate
Mosaic tiles are separate visits, but slew takes less time
SUMMARY:
Writing Proposals / Planning Observations
Phase 1: Input via template … specify scheduling details up front!
Improves schedulability of approved programs.
Ask TAC to treat constraints as a limited resource to be managed.
Integrated Planning Tool simplifies and streamlines this process.
It’s easy! It’s fun!
Phase 2: Tweaking … only if required
For NIRSpec/MOS:
Phase 2.5: Finalizing an MSA file once a precursor finder image
(e.g., with NIRCam) is available.
Template input flows directly into the PPS with minimal
human interaction. Inputs are translated into AD script
parameters, which implement activities onboard JWST.
What does a GO/GTO NEED?
TOOLS*
These tools are the interface between a GO/GTO
and the complex “under-the-hood” capabilities
required to operate JWST and its SIs efficiently.
* An S&OC Law of Self Preservation:
When confronted with complex Science Instruments, it's cheaper to provide good tools than to help 1000 observers one-by-one.