Design-a-Mission Group Projects

1. Design-a-Mission Group Projects 2014 Sagan Summer Workshop “Imaging Planets and Disks” July 21, 2014

2. What is this group project about? • 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. NASA Keck MOWG - D. Gelino

3. Which group should I choose? Groups 1 & 2: Probe-scale mission with Coronagraph Cost requirement: Under $1.5 Billion Primary science goal: Maximize observations of cold Jupiters Secondary science goal: Estimate potential capability of detecting other types of planets Groups 3 & 4:Probe-scale mission with Starshade Cost requirement: Under $1.5 Billion Primary science goal: Maximize observations of cold Jupiters Secondary science goal: Estimate potential capability of detecting other types of planets Groups 5 & 6: Medium-scale mission with Coronagraph Cost requirement: Under $4 Billion Primary science goal: Maximize observations of exoEarth candidates Secondary science goal: Estimate potential capability of detecting other types of planets NASA Keck MOWG - D. Gelino

4. Which group should I choose? Groups 7 & 8: Medium-scale mission with Starshade Cost requirement: Under $4 Billion Primary science goal: Maximize observations of exoEarth candidates Secondary science goal: Estimate potential capability of detecting other types of planets Groups 9& 10: Flagship-scale mission with Coronagraph Cost requirement: Under $12 Billion Primary science goal: Maximize observations of exoEarth candidates Secondary science goal: Estimate potential capability of detecting other types of planets Groups 11 & 12: Flagship-scale mission with Starshade Cost requirement: Under $12 Billion Primary science goal: Maximize observations of exoEarth candidates Secondary science goal: Estimate potential capability of detecting other types of planets NASA Keck MOWG - D. Gelino

5. What Questions Do I need to Answer? • What is the name of your mission and its primary goals? • Have fun with an acronym and logo if you like! • Define the telescope and instrument • Size • Coronagraph or starshade • Contrast • Inner Working Angle • Mission Lifetime • Any other modifications to default parameters • Estimate total mission cost • Present potential yield for each type of exoplanet • Earths, Jupiters, Neptunes, warm mini-Neptunes • Present yield as a function of astrophysical uncertainty • exozodilevel • eta_planet • Present any lessons learned (e.g. yield scaling relationships) NASA Keck MOWG - D. Gelino

6. Designing a Mission:Calculating Science Yields Christopher Stark (NASA GSFC, NPP) Aki Roberge (NASA GSFC) Avi Mandell (NASA GSFC) Tyler Robinson (U of Washington)

7. Designing a Mission: The Role of a Yield Calculator • Science goals determine a certain type of observation needed for some number of planets • Make a tool (aka. DRM code) that calculates approximate yields as functions of gross astrophysical and mission parameters • Use it to figure out what those parameters need to be to satisfy #1 • Take those parameters to the engineers • Iterate until satisfied

8. Inputs to the DRM DRM Exoplanet yield

9. How To Calculate Planet Yield: Completeness texpose Too faint IWA “Completeness” = the chance of observing a given planet around a given star if that planet exists Calculated via a Monte Carlo simulation with synthetic planets Depends on distance to star, planet’s orbit, radius, albedo, and phase function, and the exposure time for the required SNR

10. How To Calculate Planet Yield: Exposure Time (Planet count rate) + 2 × (Background count rate) t = (Planet SNR)2 × (Planet count rate)2 Background count rate = Leaked starlight + Zodiacal light + Exozodiacal light Image: Stefan Seip Give’on et al. (2007) Kalas et al. 2005

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

12. 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 …

13. 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

14. 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

15. Sagan Summer WorkshopMission Group Project: Cost Estimation Tools Keith Warfield (JPL) Vritika Singh (JPL) July 21, 2014

16. The Mission Costing Process • Define the telescope, coronagraph / starshade • 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. • Choose orbit • Sheet calculates data volume, rate and downlink • Sheet calculates pointing requirements • Select spacecraft bus • Sheet calculates launch mass • Select launch vehicle • Estimate total mission cost • … then iterate

17. Coronagraph/Telescope Flight System Sizing

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

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

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

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

22. Launch Vehicle Selection Sheet • Select a launch vehicle with higher capacity than the launch mass and power worksheet • Minimize launch cost The technical data in this document is controlled under the U.S. Export Regulations, release to foreign persons may require an export authorization.

23. Starshade Flight System Sizing

24. Starshade Diameter Sensitivities

25. Spacecraft Choices • Select a spacecraft suitable for the mission • Can it support the payload? • Can it support the intended mission design life? • Does spacecraftchoice put constraints on launch vehiclechoice?

26. 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

27. Cost Estimation

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

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

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