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Airships as an Earth and Space
Science Platform
Jason Rhodes (Jet Propulsion Laboratory, California Institute of
Technology)
ESAACT Seminar Series
May 21, 2021
Airships Challenge development Leads: Alina Kiessling, Ernesto Diaz
© 2021, government sponsorship acknowledged. The cost information contained in this document is of a budgetary and planning nature and is intended
for informational purposes only. It does not constitute a commitment on the part of JPL and/or Caltech.

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What is an airship?
An airship is a powered, maneuverable, lighter-
than-air vehicle

At 20 km, you’re above 95% atm

16,000 - 40,000 ft
Hybrids
Stratospheric
60,000 - 75,000 ft
< 12,500 ft
OPERATIONAL
ALTITUDE
Intermediate
Low Altitude
heavy cargo

a New Horizon for Science
Keck Institute Study
Co-Leads: S. Miller (UCI/Caltech), J. Rhodes (JPL),
L. Hillenbrand (Caltech), R. Fesen (Dartmouth)
• Geoffrey Blake - Caltech
• Jeff Booth - JPL
• David Carlile - Lockheed
Martin
• Frederick Edworthy - Aeros
• Brent Freeze - Sorlox Corp.
• Randall Friedl - JPL
• Paul Goldsmith - JPL
• Jeffery Hall - JPL
• Scott Hoffman - Northrop
Grumman
• Scott Hovarter - Lockheed
Martin
• Rebecca Jensen-Clem -
Caltech
• Ross Jones - JPL
• Jens Kauffmann - Caltech
• Alina Kiessling - JPL
• Oliver King - Caltech
• Timothy Lachenmeier - Near
Space Corporation
• Steven Lord - Caltech
• Jessica Neu - JPL
• Gregory Quetin - UofW
• Alan Ram - Northrop
Grumman
• Stanley Sander - JPL
• Marc Simard - JPL
• Steve Smith - Southwest
Research Institute
• Sara Susca - JPL
• Abigail Swann - UofW
• Eliot Young - Southwest
Research Institute
• Thomas Zambrano -
AeroVironment, Inc.
Blue Devil II
HAA - Lockheed Martin
Aeroscraft
ML86X -
Aeros
Titan Aerobot -
Near Space Corporation
LEM-V -
Northrop Grumman
HiSentinel -
Southwest Research
Institute

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KISS Study
http://kiss.caltech.edu/study/airship/
http://kiss.caltech.edu/study/airship/final-report.pdf

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Study Outcome
Three recommendations:
I. A. Establish a roadmap toward >60 kft observatory platforms for Earth, atmospheric and space
sciences. We found these platforms to be highly desirable and well-motivated. To make progress, we
envision a roadmap as follows:
i. Demonstrate high-altitude airships as a viable platform solution to capability gaps via a
prize/challenge.
ii. Launch path-finder(s) for science including site survey and new stratospheric instrument
technology.
iii. Develop and launch high-altitude, stratospheric observatory(ies).
B. Build a consortium to educate the wider scientific community about the scientific potential of
affordable stratospheric platforms and to further communicate to industry the needs of scientists.
II. A. Identify and develop existing airships as science platforms immediately to be leveraged for
the well- motivated Earth and Atmospheric science outlined in earlier chapters.
B. Consortium-build to move low-altitude airships to mid-altitudes for improved capability-gap
solutions in Earth and atmospheric science observations.
III. Develop the first successful stratospheric tethered aerostat platform to support many of the
high-altitude airship platform science goals at potentially an order-of-magnitude less cost.

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Why Not Heavier than Air?
• NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5m infrared
telescope mounted in a Boeing 747.
• SOFIA’s operating altitude is 13.7km. Airships will operate at 20km, opening up more
wavelengths and providing greater resolution.
• Operating costs ~$85M per year (~$1.7B over a 20 year lifetime) for up to 100 flights per
year. The cost of operating a single airship mission could be an order of magnitude lower
than SOFIA with similar (or longer) durations of operation.
• There is only one SOFIA, but it may be possible to launch many airship missions
simultaneously.
• SOFIA is restricted to its infrared telescope. Airships can be a platform for many kinds of
instrument (e.g. Earth observation, Planetary science, astrophysics etc).
• Other proposed “heavier-than-air” platforms have similar altitude and cost restrictions.
Figure Credit: NASA

Atmospheric Wavelength
Absorption
Figure Credit: STSci/JHU/NASA
10km
50km
85km
500km

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Why 20km?
• Sweet spot with enough air to push against, but high enough to be above 95% of
atmosphere
• Winds at lower altitudes are higher and more turbulent
• Higher than planes, lower than balloons
Source: COSPAR International Reference Atmosphere
http://nssdc.gsfc.nasa.gov/space/model/atmos/cospar1.html
Dryden Wind Turbulence Model
20km

NASA Centennial Challenges
• “NASA Centennial Challenges were initiated in
2005 to directly engage the public in the process
of advanced technology development”
• The program offers incentive prizes to generate
revolutionary solutions to problems of interest to
NASA
• The 20-20-20 Airships Challenge is a perfect fit to
this program

The Challenge
• NASA Centennial Challenge in
development to build a stratospheric
airship as a science platform
(www.centennialchallenges.nasa.gov)
• Tier1 (Tier2) of the challenge is to
launch an airship to 20km for 20hrs
(200hrs) with a 20kg (200kg) payload
and maintain a station (and maneuver
a course) for the duration of the flight.
• Airships must show scalability to longer
durations and larger payloads.
• Anticipated $3-5M prize pool
For more information, contact challenge development leads:
Alina Kiessling Alina.A.Kiessling@jpl.nasa.gov
Ernesto Diaz Ernesto.Diaz@jpl.nasa.gov
The 20-20-20 Airship Challenge
Motivation
• There are few opportunities for space
missions in astronomy and Earth science.
• Airships (powered, maneuverable,
lighter-than-air vehicles) could offer
significant gains in observing time, sky
and ground coverage, data downlink
capability, and continuity of observations
over existing suborbital options at
competitive prices.
• We seek to spur private industry to
demonstrate the capability for sustained
airship flights as astronomy and Earth
science platforms and Industrial
applications.

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Technological Motivation
• Airships provide almost space-like observations for a fraction of the cost of a
space mission.
— NASA’s Explorer program costs at minimum $120M per mission
— NASA/ESA Flagship James Webb Space Telescope (JWST) has a total cost of ~$10B
• Airship missions will be faster to develop than space missions.
— JWST was first proposed in 1996, it will finally launch in 2018 2021.
— NASA’s Roman Space Telescope was first proposed in 2010, but it utilized mature mission
designs that had been studied for a decade. It will launch in ~2024 2026.
— NASA’s Orbiting Carbon Observatory (OCO) was first proposed in 2000. It launched in 2009 but
a failure at launch destroyed the instrument. OCO2 was built primarily using spare parts from
OCO and was finally launched in 2014.
— It is time consuming, expensive and difficult to develop and launch space missions and we don’t
want to wait decades for new ideas to be tested.
— The lower cost of airships will enable missions to be launched more frequently.

Requirements
• Must demonstrate 20 hr at >20 km altitude while carrying a 20 kg payload (Tier 1).
• Must demonstrate 200 hr at >20 km altitude while carrying a 200 kg payload (Tier 2).
• Must station keep to a 20km diameter.
• Must demonstrate controlled descent and successful payload recovery.
– Requirement will be for controlled descent of only the rigid components but most
importantly, the payload.
– Most concepts of stratospheric airships have consumable hulls, and only the rigid
components are reusable.
• Airship must be “scalable” to longer durations and larger payloads.
– Teams are not to rely on expendables for station keeping (inflation/attitude control
afloat). If a concept uses too much propellant or other consumable to stay afloat
then it may not scale to weeks/months at altitude.
– Better option would be replenishable power sources. Teams will have to show their
scalable designs at PDR/CDR type review where panel of experts will determine if the
feasibility of scalability.
– Must be operable at wide range of latitude (e.g some designs only work at the
equator)
– Must be able to follow a simple course (A to B, triangle, square) in Tier 2

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HIGH-ALTITUDE AIRSHIP RESEARCH
STATION
Multi-vantage Earth-sensing and Atmospheric
Studies
Multi-wavelength Astrophysics and Cosmology
Molecules
hidden
from
ALMA
Discover
THz
sky
Interferometry
of proto-
planetary
disks or black
holes
Planetary Science from Earth and Beyond
Vertical
profiles
of the
carbon-cycle
Persistent
stare on any
part of sky
or Earth
http://adsabs.harvard.edu/abs/2014arXiv1402.6706M

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Earth Science
Weather event following, urban monitoring, fire detection
Image Credit: NASA Goddard MODIS Rapid Response Team

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Industry
Google Loon (http://www.google.com/loon/how/)
Telecommunications, asset tracking, remote site monitoring, field
communication
Google, SpaceX,Facebook all want to provide internet to the world
Google uses balloons (Loon), Facebook uses drones, SpaceX uses
cubesats

Health Impacts of Gaseous and Particulate Pollutants
Science case:
• We do not have continuous spatial
coverage measurements of pollutants
that adversely affect human health and
ecosystems at the spatial and temporal
resolution needed to determine
exposure
• Ozone, Particulate Matter, SO2,
NOx, Non methane hydrocarbons
Instrument:
One or more of (depending on power budget.
Could timeshare the power):
• Multiangle Imaging Spectropolarimeter
(AirMSPI currently flying)
• 200 watts, 85kg
• Imaging Fourier Transform Spectroscopy
(FTS)
• 150 watts, 82kg
• Grating spectrometers
• TBD watts, ~40kg
Why this is important to NASA:
• Addresses major NASA Earth science
focus areas
• Atmospheric composition
• Carbon cycle & ecosystems
• Climate variability & change
• Human Health & Air Quality is an
emerging priority under the Applied
Sciences program
How airships enable this science:
• Resolution at the sub-neighborhood
scale needed for health studies
• Ability to stare at a single location
continuously
Development names: Jessica Neu (JPL), Dave
Diner (JPL)

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Challenge in the News
http://www.forbes.com/sites/brucedorminey/2014/07/29/astronomy-from-high-altitude-airships/ http://www.nytimes.com/2014/08/26/science/airships-that-carry-science-into-the-stratosphere.html?_r=0
http://www.latimes.com/science/science
now/la-sci-sn-nasa-airship-challenge-jpl-
telescope-astronomy-20141202-
story.html
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