design-a-mission group projects

National Aeronautics and Space AdministrationJet Propulsion LaboratoryCalifornia Institute of TechnologyN

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Design-a-MissionGroup Projects

July 21, 2014

2014 Sagan Summer Workshop“Imaging Planets and Disks”


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NASA Keck MOWG - D. Gelino 2

What is this group project about?

February 26, 2013

Design your own mission to detect exoplanets

Three different mission classes: Probe, Medium-scale, Flagship

Two different high-contrast instruments: Coronagraph and Starshade

Each class and hardware setup combination has a cost cap and set of science goals

Two groups for each type of mission: see who can observe the most planets!

You will sign up for a group on the sheets provided, and start working towards your 7-10 min presentation to be given on Friday afternoon.


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Which group should I choose?

February 26, 2013

Groups 1 & 2: Probe-scale mission with CoronagraphCost requirement: Under $1.5 BillionPrimary science goal: Maximize observations of cold JupitersSecondary science goal: Estimate potential capability of

detecting other types of planets

Groups 3 & 4: Probe-scale mission with StarshadeCost requirement: Under $1.5 BillionPrimary science goal: Maximize observations of cold JupitersSecondary science goal: Estimate potential capability of


Groups 5 & 6: Medium-scale mission with CoronagraphCost requirement: Under $4 BillionPrimary science goal: Maximize observations of exoEarth

candidatesSecondary science goal: Estimate potential capability of



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Which group should I choose?

February 26, 2013

Groups 7 & 8: Medium-scale mission with StarshadeCost requirement: Under $4 BillionPrimary science goal: Maximize observations of exoEarth

candidatesSecondary science goal: Estimate potential capability of detecting

other types of planets

Groups 9 & 10: Flagship-scale mission with CoronagraphCost requirement: Under $12 BillionPrimary science goal: Maximize observations of exoEarth



Groups 11 & 12: Flagship-scale mission with StarshadeCost requirement: Under $12 BillionPrimary science goal: Maximize observations of exoEarth




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What Questions Do I need to Answer?

February 26, 2013

1. What is the name of your mission and its primary goals?

a. Have fun with an acronym and logo if you like!

2. Define the telescope and instrument

a. Size

b. Coronagraph or starshade

c. Contrast

d. Inner Working Angle

e. Mission Lifetime

f. Any other modifications to default parameters

3. Estimate total mission cost

4. Present potential yield for each type of exoplanet

a. Earths, Jupiters, Neptunes, warm mini-Neptunes

5. Present yield as a function of astrophysical uncertainty

a. exozodi level

b. eta_planet

6. Present any lessons learned (e.g. yield scaling relationships)

Designing a Mission:Calculating Science Yields

Christopher Stark (NASA GSFC, NPP)

Aki Roberge (NASA GSFC)Avi Mandell (NASA GSFC)

Tyler Robinson (U of Washington)

Designing a Mission: The Role of a Yield Calculator

1. Science goals determine a certain type of observation needed for some number of planets

2. Make a tool (aka. DRM code) that calculates approximate yields as functions of gross astrophysical and mission parameters

3. Use it to figure out what those parameters need to be to satisfy #1

4. Take those parameters to the engineers

5. Iterate until satisfied

Inputs to the DRM

DRM

Exoplanet yield

9

Depends on distance to star, planet’s orbit, radius, albedo, and phase function, and the exposure time for the required SNR

“Completeness” = the chance of observing a given planet around a given star if that planet exists

Too faint

texpose

How To Calculate Planet Yield:Completeness

Calculated via a Monte Carlo simulation with synthetic planets

IWA

10

t = (Planet SNR)2 ×(Planet count rate) + 2 × (Background count rate)

(Planet count rate)2

Background count rate =

Leaked starlight + Zodiacal light + Exozodiacal light

Image: Stefan Seip

Kalas et al. 2005

Give’on et al. (2007)

How To Calculate Planet Yield:Exposure Time

How To Calculate Planet Yield:Optimizing Exposure Time to Maximize Yield

Starting the Hands-On Exercise• Start VNC Viewer. Log in

• Open a Terminal window

– Under Applications / System Tools

• Type …

> cd Mon

> cp /ssw/Mon/* .

• This will copy the yield tool and two costing spreadsheets to your /home/Mon directory

• Begin Quick Start guide examples …

Inner Working Angle

• IWA entered into yield tool in arcseconds• For coronagraphs,

• IWA = a × λ / D• OWA = b × λ / D• λ = 0.55 μm, a > 2, b < 20• You have to calculate what a, b your choices

correspond to before using the cost calculator

• For starshades, IWA can be anything. No OWA• Small IWAs will increase the starshade / telescope

separation and the retargeting times

A Few Words About Costs

• The cost tools are Open Office spreadsheets, one for coronagraphs, one for starshades• May look complicated but are not hard to use

• These are estimates of what your missions will cost

• The point of having cost caps is to put a constraint on your design choices• So you don’t all order up the premium versions of

everything

Exoplanet Exploration Program

Click to edit Master title style

Keith Warfield (JPL)

Vritika Singh (JPL)

July 21, 2014

Keith Warfield (JPL)

Vritika Singh (JPL)

July 21, 2014

Sagan Summer WorkshopMission Group Project: Cost Estimation Tools

Sagan Summer WorkshopMission Group Project: Cost Estimation Tools


The Mission Costing Process

1. Define the telescope, coronagraph / starshade

2. Input chosen parameters on front worksheet of spreadsheet• For some parameters, have to choose from a drop-down list

of options. Choose option closest to your design value.

3. Choose orbit

4. Sheet calculates data volume, rate and downlink

5. Sheet calculates pointing requirements

6. Select spacecraft bus

7. Sheet calculates launch mass

8. Select launch vehicle

9. Estimate total mission cost

10. … then iterate


Coronagraph/Telescope Flight System Sizing


Design Worksheet

• Fill in all input information as an initial starting point• Orbit choice requires telecom data volume evaluation and mission duration choice• Spacecraft and Launch Vehicle are selected from lists on other worksheets

18The technical data in this document is controlled under the U.S. Export Regulations, release to foreign persons may require an export authorization.

System Parameter Option ADiameter (m) 1.0 mOn-Axis (0) or Off-Axis (1) 0Raw Contrast (log10) -8IWA (milliarcsec) (75-200) 200 masecSpectral Bands (number) 3Bandwidth per Band (%) 10%

Detector CCD (1), CMOS (2), EMCCD (3) 2Mission Duration Lifetime (years) 5 yrsOrbit LEO (1), L2 (2), Trailing Orbit (3), or GEO (4) 2Spacecraft Spacecraft Configuration Selection Spacecraft DLaunch Vehicle Launch Vehicle Selection L/V B

Payload Driven Spacecraft Pointing Requirement 0.50 asecPayload Power Requirement 281 WData Generated per Day 691 Mb/dayPayload Mass 520 kg Coronagraph Mass 220 kg Telescope Mass 300 kgLaunch Capability 3700 kgLaunch Mass 2079 kgLaunch Margin 1621 kgCost (FY14) $725 M

Coronagraph Instrument & Telescope

Overall Mass and Cost

Inputs 1

Telescope

Coronagraph Instrument

Inputs 2

Auto Outputs


Orbit and Telecom Sheets


• Trading telecom needs vs. station keeping requirements vs. mission duration

• All subsystems can be impacted by the decision but Telecom is the most important

• Make sure the daily coronagraph data can fits with the orbit capability

• Select a spacecraft offering the required telecom band

Telecom Capability

L2 Earth Trailing

S 20 n/a

X 3000 300/(ops year 2̂)

Ka 13000 1300/(ops year 2̂)

Max Downlink Duration 8 hrs/day 8hrs/day

S 576 n/a

X 86,400 8640/(ops year 2̂)

Ka 374,400 37400/(ops year 2̂)

Max Downlink Rate (kbps)

Max Daily Data Volume (Mb/day)

Earth Trailing L2Typical Downlink Band X/Ka X/KaTypical Downlink Antenna

HGA MGA/HGA

Ground Stations DSN DSN

Con’sLarge link distance; higher cost launch; limited extended mission

Station keeping required; higher cost launch

Pro’sNo station keeping, extremely quiescent environment

Constant geometry; extended mission option


Spacecraft Selection Sheet

• Select a spacecraft with:– Sufficient payload mass and power capability– Adequate pointing performance (requirement set by telescope)– Correct mission design life– Correct telecom band


Spacecraft A Spacecraft B Spacecraft C Spacecraft DSpacecraft

ESpacecraft F

Payload Power (OAV) (EOL) W (EOL) 50 125 730 650 1000 3000

Payload Mass Limit of Bus kg 70 200 380 650 1700 2400

Bus Dry mass (w/o Payload) kg 60 125 600 500 1500 2000

Science Data Storage capability Mbit 500 20,000 134,000 200,000 51,000 102,000

Pointing Control arcsec 5 5 3 0.3 0.2 0.15

Slewrate deg/min 60 390 240 120 50 5

Mission Design Life yrs 1 2 5* 5* >5* >5*

Compatible LVs (names) L/V A only All L/V's All L/V's All L/V's All L/V's All L/V's

Downlink Band S-band S-BandS-band and X-

bandS-band and X-

bandX-band and

Ka-bandX-band and

Ka-band

Propulsion type NoneBlowdown hydrazine

Blowdown hydrazine

Blowdown hydrazine

Blowdown hydrazine

Blowdown hydrazine

Cost $ FY14 $ 26 M $ 53 M $ 90 M $ 142 M $ 174 M $ 264 M


Launch Mass and Spacecraft Power Estimation Sheet

• Worksheet used for estimating power requirement for spacecraft selection, and launch mass for launch vehicle selection

• JPL standard mass and power margins are included


SYSTEMS WORKSHEET:

Subsys CBE+ Mode 1 Mode 2 Mode 3 Mode 4Mass Cont. Cont. Power Power Power Power(kg) % (kg) (W) (W) (W) (W)

Mass Fraction

Launch Science Science & Telecom

Safe

Chronograph 21% 220 43% 314.6 0 168 168 0

Telescope 29% 300.0 43% 429.0 0 113 113 0

Payload Total 50% 520.0 43% 743.6 0 281 281 0

Spacecraft Bus

Spacecraft 48% 500.0 30% 650.0 100 100 150 100

S/C-Side Adapter 2% 25.0 5% 26.3

Bus Total 525.0 29% 676.3

Spacecraft Total (Dry) 1045.0 36% 1419.9 100 381 431 100

Subsystem Heritage Contingency 374.9 36% 36%

System Contingency 74.5 7% 7% 0 121 121 0

Spacecraft with Contingency 1494 of total w/o addl pld 100 502 552 100

Propellant & Pressurant1 2% 40.0

Spacecraft Total (Wet) 2054

L/V-Side Adapter 25.0

Launch Mass 2079

Launch Vehicle Capability 3700

Launch Vehicle Margin 1620.7

JPL Design Principles Margin 57%

Spacecraft - Option 1

30% required


Launch Vehicle Selection Sheet

• Select a launch vehicle with higher capacity than the launch mass and power worksheet

• Minimize launch cost


600km LEO L2Earth

TrailingGEO

Cost($FY14)

L/V A 1000 kg N/A N/A N/A $ 90 M

L/V B 14500 kg 3700 kg 3650 kg 3700 kg $ 142 M

L/V C 13700 kg 4788 kg 4838 kg 5200 kg $ 274 M

L/V D 16300 kg 6150 kg 6100 kg 6750 kg $ 306 M

L/V E 21430 kg 9380 kg 9225 kg 12710 kg $ 422 M

L/V Max. Capacity


Starshade Flight System Sizing


Starshade Diameter Sensitivities

Starshade Dia. (m)

Mass (kg)

Cost ($M FY14)

30 635 $120

32 680 $125

34 725 $130

36 775 $140

38 825 $150

40 880 $165

42 935 $200


Spacecraft Choices

• Select a spacecraft suitable for the mission– Can it support the payload?– Can it support the intended mission design life?– Does spacecraft choice put constraints on launch vehicle choice?

Spacecraft W

Spacecraft X

Spacecraft Y

Spacecraft Z

Payload Power (BOL) W (BOL) 730 650 1000 3000

Payload Mass Limit of Bus kg 675 850 1700 2400

Bus Dry mass (w/o Payload) kg 600 500 1500 2000

Slewrate deg/min 240 120 50 5

Mission Design Life yrs 2 3 5 >5

Compatible LVs (names)All L/V's

except L/V FAll L/V's

except L/V FAll L/V's

except L/V F All L/V's

Downlink BandS-band and X-

bandS-band and

X-bandX-band and

Ka-bandX-band and

Ka-band

Propulsion type Blowdown hydrazine

Blowdown hydrazine

Monoprop or biprop

Monoprop or biprop

Cost $ FY14$ 120 M $ 165 M $ 240 M $ 300 M


Launch Vehicle Choices

• Add starshade mass and spacecraft dry mass. Then add 400 kg/year for propellant. This is the launch mass.

• Select a launch vehicle with adequate capacity for the intended destination

600km LEO

L2Earth

TrailingGEO

Cost($FY14)

L/V A 1000 kg N/A N/A N/A $ 90 M

L/V B 14500 kg 3700 kg 3650 kg 3700 kg $ 142 M

L/V C 13700 kg 4788 kg 4638 kg 5200 kg $ 274 M

L/V D 16300 kg 6150 kg 6100 kg 6750 kg $ 306 M

L/V E 21430 kg 9380 kg 9225 kg 12710 kg $ 422 M

L/V Max. Capacity


Cost Estimation

WBS Elements Total

Project Cost ($ FY14) $803 M Basis of EstimateDevelopment Cost (Phases A - D) $505 M Sum

01.0 Project Management $17 M 5% of WBS 05 thru 10 and 12

02.0 Project Systems Engineering $17 M 5% of WBS 05 thru 10 and 12

03.0 Mission Assurance $14 M 4% of WBS 05 thru 10 and 12

04.0 Science $5 M

05.0 Payload System $130 M Sum

Starshade $130 M Starshade look up table

06.0 Flight System $142 M S/C look up table

07.0 Mission Operations Preparation $15 M JPL OTS Earth-orbiting Missions (flat cost input)

09.0 Ground Data Systems $20 M JPL OTS Earth-orbiting Missions (flat cost input)

10.0 ATLO $25 M JPL OTS Earth-orbiting Missions (flat cost input)

11.0 Education and Public Outreach $2 M 0.5% of WBS 05 thru 10 and 12

12.0 Mission and Navigation Design $3 M Guess

Development Reserves $115 M 30% of WBS 01 thru 12 except 08

Operations Cost (Phases E - F) $156 M

Operations $125 M $25M/year

Operations Reserves $31 M 25% of operations

8.0 Launch Vehicle $142 M L/V look up table

COST SUMMARY (FY2014 $M) - Option 1


Backup



Payload Sheet

• Coronagraph parameters are estimated for input requirements

• Telescope selected from a pick list– Telescope sets a spacecraft pointing requirement which limits spacecraft choices


CoronagraphIWA

Raw Contrast

Spectral Bands

Bandwidth per Band

Detector Mass Power Data Rate Cost

milliarcsec Log 10 number (%) kg W Mbps FY14 $M

Option 1 200 1 3 1 2 220 168 0.008 78

Option 2 0 No Input 0 No Input 0 -10 #NUM! 0.000 #NUM!

Option 3 0 No Input 0 No Input 0 -10 #NUM! 0.000 #NUM!

Telescope Mass Power Data rate Cost

($ FY14)Visible

0.5m Telescope 30 25 n/a $ 16 M 0%

1.0m Telescope 300 113 n/a $ 42 M 0%

1.5m Telescope 600 185 n/a Pointing $ 142 M 0%




SPACECRAFT Pointing Requirement

Tech. Dev.

Off-Axis Cost Adjustment

(kg) (W) (kbps)(asec)Visible

1

0.5

0.3

0.21

0.17

0.15

- Cyan cells are inputs that have been transferred from the Design Worksheet to this worksheet. - Yellow cells are look-up table values. - This sheet is locked; cells cannot be modified.

Notes - Purple cells have automatic calculations to provide the necessary outputs.


Cost Estimation Worksheet

• Cost estimate is for the total project cost• Require inputs:

– Coronagraph cost– Telescope cost– Spacecraft cost– Mission duration to set operations costs


WBS Elements Total

Project Cost ($ FY14) $725 M Basis of EstimateDevelopment Cost (Phases A - D) $427 M Sum

01.0 Project Management $14 M JPL percentage02.0 Project Systems Engineering $14 M JPL percentage03.0 Mission Assurance $11 M JPL percentage04.0 Science $5 M05.0 Payload System $121 M Sum

Chronograph $78 MTelescope $42 M

06.0 Flight System $142 M07.0 Mission Operations Preparation $5 M JPL OTS Earth-orbiting Missions09.0 Ground Data Systems $5 M JPL OTS Earth-orbiting Missions10.0 ATLO $5 M JPL OTS Earth-orbiting Missions11.0 Education and Public Outreach $1 M NASA percentage12.0 Mission and Navigation Design $3 M GuessDevelopment Reserves $99 M 30% NASA Requirement

Operations Cost (Phases E - F) $156 MOperations $125 M $25M/year Earth Mission (Sci + Ops)Operations Reserves $31 M 25% NASA Requirement

8.0 Launch Vehicle $142 M Not included in AO

COST SUMMARY (FY2014 $M) - Option 1

design-a-mission group projects

Documents

billionprimary science

science goalstwo groups

mediumscale mission

probescale mission

flagshipscale mission

potential capability

type of mission

types of planets groups