KECK INSTITUTE FOR SPACE STUDIES

       

Workshop: Non-Nuclear Exploration of the Solar System

April 12 - 15, 2021
California Institute of Technology - Pasadena, CA 91125

Workshop Overview:

The proposed study would investigate a system architecture with the potential to provide solar-powered transportation to the outer planets and solar power in orbit at the destination. This architecture consists of two key features:

  • Very large, deployable solar arrays to provide power at the outer planets (roughly a few thousand square meters per wing with areal densities of order ~100 g/m2).
  • Direct-drive electric propulsion systems to take advantage of the high-power provided by very large solar arrays to deliver them to their destinations. Ideally, such electric propulsion systems require the development of high-voltage solar arrays with output voltages of order 1 kV and should be throttleable over a large input power range (≥100:1).

We will take build this architectural approach with broad community, identify and address feasibility issues, and define a roadmap of useful technology demonstration and operational missions that lead to the desired end state—an alternative approach for solar system exploration that requires no use of nuclear power sources. The conceptual, non-nuclear exploration architecture would include: solar-powered orbiters, battery-powered landers and rovers, and solar-powered sample return vehicles.
There are four emerging technologies that make this the right time to investigate the potential and limitations of a non-nuclear solar system exploration architecture. The proposed study will investigate how these technologies can be combined to enable this new exploration capability:

  • Development of very lightweight, large-scale photovoltaic arrays with a per wing area of order 3000 m2 and areal densities in the range 100 to 200 g/m2. These performance values are consistent with the objectives of the current space solar power work at Caltech.
  • Development of solar cells that work efficiently under Low Intensity Low Temperature (LILT) conditions at solar intensities corresponding to solar ranges of 20 to 30 au, or the development of concentrator solar arrays with relatively low concentration-ratios (~10:1).
  • Development of solar arrays that have output voltages of 1 to 2 kV that can operate successfully in the plasma environment created by electric propulsion systems.
  • Development of direct-drive, electric propulsion systems with a large input power throttling range coupled with the high-voltage solar arrays.

Monday, April 12, 2021

Welcome, Introduction and Context Setting Talks

Time
Event
Speaker
7:45 - 8:00

Welcome to the workshop! Please get yourself settled into the Think Tank room early to leave plenty of time for unexpected technical hitches (test your mic, grab some coffee or tea), and informally get to know your fellow participants as we all get ready to start at the top of the hour.

8:00 - 9:30 

Logistics
Study vision
Goals and expectations for workshop
Participant Introductions (30 seconds each)
Zoom group photo

Michele Judd
John Brophy

9:30 - 10:00

Context Talk: Space Solar Power Project Overview
(20 mins + 10 mins discussion)

 

Sergio Pellegrino
Harry Atwater
10:00 - 10:30

Break - Get up and MOVE for at least 10 minutes ;-) and then meet folks in Gather Town, think about the study's vision, or discuss context talk

10:30 - 11:00

Context Talk: Advanced Photovoltaics for Low Intensity Low Temperature (LILT)
(20 mins + 10 mins discussion)

Andreea Boca
Jonathan Grandidier
11:00 - 11:30

Context Talk: Wireless Power Transfer (optical and RF)
(20 mins + 10 mins discussion)

Philip Lubin
11:30 - Noon

Context Talk: Electric Propulsion State of the Art
(20 mins + 10 mins discussion)

Elaine Petro
Colleen Marrese-Reading

Noon - 1:00

Grab lunch! Hang out in Gather Town with old and new friends if you like or help with your kid's homework, walk the dog - just take care of yourself.

1:00 - 1:30 Context Talk: Solar Sails/Large Deployable Structures
(20 mins + 10 mins discussion)

Les Johnson
1:30 - 2:00

Breakout Group discussion, sign-ups

All
2:00 - 5:00

Gather Town remains open for:
- Homework & Research (group / individual activity)
- Setting up informal conversations/collaborations

5:00 Day 1 ends

Tuesday, April 13, 2021

Time
Event
Speaker
7:45 - 8:00

Pop into Gather Town, check out the announcement board, meet up with your early time zone colleagues or explore the new rooms in Gather Town.

8:00 - 8:10

Logistics
Overview of day
Zoom group photo

Michele Judd
Team Lead

8:10 - 8:25

Lightning Talks:
Outer Planets Science
Trajectories for SEP outer planet missions and requirements

Jennifer Scully
Steve McCarthy
8:25 - 8:35 Discussion of Breakout Sessions throughout workshop John Brophy
8:35 - 10:00

Breakout Session #1

All
10:00 - 10:30

Break - Get up and MOVE for at least 10 minutes ;-) and then meet folks in Gather Town, think about today's focus area and breakout sessions

10:30 - 11:00

Report outs from Breakout Sessions (5 minutes each)

Breakout Teams
11:00 - 11:45

Lightning Talks:
Perovskite solar cell production
Perovskite solar cell technology status
Perovskite solar cell technology development for space applications
State of the art in nuclear power systems: RTGs and Fission reactors
State of the art in deployable solar arrays for deep space missions

Joseph Luther
Ian Sellers
Mike Kelzenberg
Ralph McNutt
Mike Sekerak

11:45 - 11:50

Organize Breakout Session #2

Team Leads
11:50 - 12:50 Grab lunch! Hang out in Gather Town or do what you need to to stay sane.

12:50 - 2:00

Breakout Session #2: Topic TBD

All
2:00 - 5:00

Gather Town remains open for:
- Homework & Research (group / individual activity)
- Setting up informal conversations/collaborations

5:00 Day 2 ends

Wednesday, April 14, 2021

Time
Event
Speaker
7:45 - 8:00

Pop into Gather Town, check out the announcement board, meet up with your early time zone colleagues or explore the new rooms in Gather Town.

8:00 - 8:45

Logistics
Overview of day
Group pulse
Group photo

Michele Judd
Team Lead

8:45 - 9:15

Report outs from Breakout Sessions (5 minutes each)

Breakout Teams
9:15 - 9:30

Organization of Breakout Session #3

TBD
9:30 - 10:00

Break - Get up and MOVE for at least 10 minutes ;-) and then meet folks in Gather Town, think about today's focus area and breakout sessions

10:00 - 11:30

Breakout Session #3

TBD
11:30 - 12:30

Grab lunch! Hang out in Gather Town or do what you need to to stay sane.

12:30 - 12:45

Report outs from Breakout Sessions (5 minutes each)

Breakout Teams
12:45 - 1:30 Provocative Statements ‐ Whiteboards Session All
1:30 - 2:00 Plenary Session to display and discuss results from Whiteboards Session

All
2:00 - 5:00

Gather Town remains open for:
- Homework & Research (group / individual activity)
- Setting up informal conversations/collaborations

5:00

Day 3 ends


Thursday, April 15, 2021

Putting it all together

Time
Event
Speaker
7:45 - 8:00

Pop into Gather Town, check out the announcement board, meet up with your early time zone colleagues or explore the new rooms in Gather Town.

8:00 - 8:10

Logistics
Overview of day
Group Photo

Michele Judd
Team Lead

8:10 - 10:00

Breakout Session #4

All
10:00 - 10:30

Break - Get up and MOVE for at least 10 minutes ;-) and then meet folks in Gather Town, think about today's focus area and breakout sessions

10:30 - 11:00

Breakout Session #4 Report Outs

All
11:00 - 11:30

Brief overview outline of the final report and writing assignments

All
11:30 - 11:45

Advocacy Plan

All
11:45 - 11:55

Reflections

All
11:55 - NOON Workshop closing

Michele Judd
NOON

Day 4 ends with pizza lunch!

2:00 - 5:00

Gather Town remains open for:
- Homework & Research (group / individual activity)
- Setting up informal conversations/collaborations


Workshop Participants:

  • Leon Alkalai – AstroLabs Enterprises
  • Harry Atwater – Caltech
  • Abi Biswas – JPL
  • Andreea Boca – JPL
  • John Brophy – JPL
  • Greg Carr – JPL
  • Artur Davoyn – UCLA
  • Bill Frazier – JPL
  • Terry Gdoutos – Caltech
  • Jonathan Grandidier – JPL
  • Kristina Hogstrom – JPL
  • Mike Paul Hughes – JPL
  • Les Johnson – NASA George C. Marshall Space Flight Center
  • Michael Kelzenberg – Caltech
  • Andrew Lee – Caltech
  • Philip Lubin – UC Santa Barbara
  • Joseph Luther – University of Colorado Boulder
  • Colleen Marrese-Reading – JPL
  • Michael Marshall – Caltech  
  • Steve McCarty – NASA Glen Research Center
  • Ralph McNutt – Johns Hopkins University, APL
  • Sergio Pellegrino – Caltech
  • Elaine Petro – Cornell University
  • James (Jay) Polk – JPL
  • Jennifer Scully – JPL
  • Michael (Mike) Sekerak – NASA Goddard Space Flight Center
  • Ian Sellers – University of Oklahoma