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CEDAR Distinguished Lecture

Choose your own adventure

Larry J. Paxton

larry.paxton@jhuapl.edu

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25 June 2026

Your nomination letter highlighted your seminal and sustained contributions to CEDAR science through pioneering ultraviolet remote sensing of the ionosphere–thermosphere system, transformative space-based instrumentation, and the development of observational datasets and models that have fundamentally advanced our understanding of thermospheric composition, auroral energy input, and equatorial plasma structures.

It also emphasized your exceptional leadership and service to the community, your role in enabling major scientific advances through experimental innovation, and your long-standing commitment to mentoring and workforce development

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Red Pill or Blue Pill?

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25 June 2026

You take the blue pill ... the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill ... you stay in Wonderland, and I show you how deep the rabbit hole goes.

Morpheus  The Matrix

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DISCLAIMER:

  • This is meant in the context of the 1999 movie The Matrix
  • First appeared in Total Recall (1990) with the red pill meaning a return to reality.
    • https://en.wikipedia.org/wiki/Red_pill_and_blue_pill
    • see also Philip K. Dick’s story “We Can Remember It for You Wholesale”
    • https://en.wikipedia.org/wiki/We_Can_Remember_It_for_You_Wholesale
  • Taking the ‘red pill’ means becoming aware of a truth about reality that can be upsetting
  • Taking the ‘blue pill’ is choosing to continue along your current path without looking beyond it.
  • In this context, it does not mean or imply a shift from liberal/progressive beliefs to extremist viewpoints.
  • See ‘pill” description at the ADL website or wikipedia
    • https://www.adl.org/resources/article/extremist-medicine-cabinet-guide-online-pills

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25 June 2026

Most importantly: be genuine, be true to yourself, believe in your intrinsic worth

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Spaceflight Instrumentation and YOU

Some thoughts on my own career, life as a human, and the realities of the world

Larry J. Paxton

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GOAL: Provide some insights into instrumentation

  • It seems as though everything is in flux.
  • However, science and technology development are still funded
    • We see turbulence at small scales
    • At large scale, budget are steady or increasing.
  • To prosper, we will need to map our capabilities and interests into the current direction.
  • We are unlikely to see a return to a purely curiosity driven approach.
  • Curiosity driven science will still be done but it will remain at a small scale.
    • Note that the NSF budget is around $7B – and Geospace is set at <$70M or ~1%
    • Note that NASA budget is around $24B and SMD is around $7B – Helio is 10% of SMD or 3% of the NASA budget

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25 June 2026

https://en.wikipedia.org/wiki/Who_Moved_My_Cheese%3F

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What do you want to do in your career?

  • Do you want to be part of a space mission?
  • Do you want to lead a satellite investigation (PI or Instrument Lead)?
  • Do you want to build an instrument? (Or cause one to be built!)
  • Do you know how an instrument is developed as a concept to answer a particular scientific question?
  • There are two paths to producing an instrument:
    • Redoing something that has been done before – the ‘tyranny of the TRL’
    • Creating a new capability – this may be easier to do outside of NASA
  • “No one ever steps in the same river twice, for it's not the same river and they’re not the same person.”�― Heraclitus 500BCE

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Change is hard...but you have the basic tools to make that change

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25 June 2026

  • You have already made the investment in learning basic science – something few people do.
  • The empirically demonstrated Logistics Curve or Pareto Distribution shows that in something like 20% of the time that it takes to achieve totally mastery you can get up to 90% of the way to total mastery.
  • OR... that you are capable of learning applications and extensions of your existing skill set.

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Why work on instruments?

  • There is a Japanese word, monozukuri, ものづくり, that refers to the ‘making of things’ but with the emphasis on the pursuit of mindfulness, discipline, and the pursuit of perfection during the act of creation.
    • Buying is not equivalent to an act of creation
  • There is a sense of mastering the craft when a space instrument finally is in space and producing data.
  • Instruments are much more of a group effort, requiring many different skills brought together, to achieve the perfection of design.
    • A satisfying design is one that works
    • A pleasing design is one that works with nothing more or less required to do the task that has been set out for it.
  • Good data products require understanding the experiment from end-to-end.
    • Space environment, spacecraft, instrument, calibration and characterization, and algorithms
    • No data product is without issues
    • Data are easy to produce – KNOWLEDGE is much harder

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The ITM questions haven’t changed for decades

  • Based on the Decadal Survey 2024 report, the overarching scientific questions for the Ionosphere, Thermosphere, and Mesosphere (ITM) domain focus on systems science, specifically how Earth's upper atmosphere acts as a highly coupled mixture of neutral gas and charged plasma
  • We need a global view - to establish that global view we need an orbital perspective on the processes
  • Orbital and groundbased assets are complementary and do not compete for the same resources
  • In this talk, I will describe the basic tools for understanding the upper atmosphere with and emphasis on far ultraviolet remote sensing.
  • I will explain how instruments are designed and some of the applications to other problems.

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25 June 2026

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CHALLENGE : Change from a ‘scarcity mindset’ to an ‘abundance mindset’

  • An abundance mindset is the belief that there are always resources and opportunities if you open your acceptance criteria, while a scarcity mindset is the belief that life is a zero-sum game with limited resources
  • Stephen Covey , Seven Habits of Highly Effective People

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25 June 2026

 

Scarcity Mindset

Abundance Mindset

Core Belief

Life is a zero-sum game

Life is abundant in its possibilities

Central Question

What is missing, lost, or unavailable?

What is available, possible, and might be created?

Others

Fear, envy, suspicion, and the belief that to succeed others must fail.

Recognize that you are valuable as are others, collaboration succeeds, success comes in many forms and timescales

Time Horizon

Short-term survival and energy spent on restricting opportunities for others and gaining access to restricted opportunities

Long-term growth, learning, and investment in others by creating opportunities.

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CHALLENGE : Change from a ‘scarcity mindset’ to an ‘abundance mindset’

  • An abundance mindset is the belief that there are always resources and opportunities if you open your acceptance criteria, while a scarcity mindset is the belief that life is a zero-sum game with limited resources
  • Stephen Covey , Seven Habits of Highly Effective People

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25 June 2026

 

Scarcity Mindset

Abundance Mindset

Core Belief

Life is a zero-sum game

Life is abundant in its possibilities

Central Question

What is missing, lost, or unavailable?

What is available, possible, and might be created?

Others

Fear, envy, suspicion, and the belief that to succeed others must fail.

Recognize that you are valuable as are others, collaboration succeeds, success comes in many forms and timescales

Time Horizon

Short-term survival and energy spent on restricting opportunities for others and gaining access to restricted opportunities

Long-term growth, learning, and investment in others by creating opportunities.

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We think small because we live small

  • The Solar Community (Nour al Rauuafi et al. 2022) have pushed for FIREFLY a mission to view the Sun from all vantage points.

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25 June 2026

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We think small because we live small

  • The Solar Community (Nour al Rauuafi et al. 2022) have pushed for FIREFLY a mission to view the Sun from all vantage points.

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25 June 2026

Firefly would enable science by viewing the Sun from all vantage points

Polar, equatorial – leading and trailing edge and farside

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What could we learn from a ‘4π’ view of the Earth?

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25 June 2026

Robert F. Kennedy (1925-1968) recast a phrase from G.B. Shaw during his 1968 presidential campaign

"Some men see things as they are and say why. I dream of things that never were and say, why not."

https://en.wikipedia.org/wiki/Robert_F._Kennedy

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We do what we can do – but we need to change

  • Our science is focused on small problems
  • This is driven by small grants
  • Which are driven by sponsor budgets
  • Which are driven by politics
  • Which is driven by ‘value statements’

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25 June 2026

https://quoteinvestigator.com/

1989, Classic Tales of Mulla Nasreddin, Retold by Houman Farzad, Translated from Persian by Diane L. Wilcox, Looking for the Missing Ring, Quote Page v,Mazda Publishers, Costa Mesa, California  -- might be over 800 years old.

You do what you can with what you have

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Larry Paxton

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Larry Paxton

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Transformative Abundance Mindset and Practicing Gratitude

The person that has lost their keys has many options:

Rideshares.

Asking for help.

Finding another source of illumination

Wait for a new dawn.

How many can you think of? Apply that to your life.

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Always start with the ‘Why?’

  • These are the themes we need to map our science to to help NASA.
  • NASA generates its input to the President’s Budget Request (PBR) through a highly structured, internal cycle called the Planning, Programming, Budgeting, and Execution (PPBE) process.
  • Themes reflect the Planning and Programming Phases of the PPBE.

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We Heard the How

  • This opens the aperture beyond the selection of DYNAMIC – DAPHNE and the GDC-Trailblazer.

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Let’s develop new instruments!

BUT – we need a ‘Why?’ this is just the ‘What’

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The realm of ITM science

  • Why do we need to understand the ITM?
  • How do we understand the ITM?
  • What do we gain/learn from that understanding?

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CHALLENGE: What do we focus on and how do we address it?

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What tools can we use to observe these processes?

  • Why do we need to understand the ITM?
  • How do we understand the ITM?
  • What do we gain/learn from that understanding?

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CHALLENGE: What do we focus on and how do we address it?

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What tools can we use to observe these processes?

  • Why do we need to understand the ITM?
  • How do we understand the ITM?
  • What do we gain/learn from that understanding?

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CHALLENGE: What do we focus on and how do we address it?

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The upper atmosphere

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The upper atmosphere

Region characterized by FUV Emissions

Region characterized by FUV Emissions

This is the Very Low Earth Orbit (VLEO) environment and it is the new frontier for satellite operations

Below 300km where orbital lifetimes without propulsion are less than 1 year

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Point At Which the Vertical Optical Depth Equals 1 Defines How Far Down Into the Atmosphere You Can See

O2 SR Continuum

O2 SR Bands

O3

FUV

FUV

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FUV Spectrum of the Earth

  • Your eye can’t see in far ultraviolet: 115 to 180nm
  • Looking down from space sample the VLEO environment
  • Upper atmosphere FUV emissions are seen against a black background (no lower atmosphere FUV signals)
  • This is because O2 absorbs light
  • http://www.kellerstudio.de/repairfaq/sam/spctrm2.jpg

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The processes that give rise to the emissions constrain the energy, momentum and continuity equations

  • From laboratory studies and more than half a century of sounding rocket observations and almost a century of ground-based spectroscopy, we know the mechanisms that produce the signatures seen in the Earth’s optical spectrum.
  • There are still many cross sections, processes, and reaction rates that are poorly known because they are difficult to measure in the lab.

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Quantum mechanics indicates the ‘selection rules’ that explain spectral transitions as ‘allowed’ or ‘forbidden’

ALLOWED (resonant scattering)

  • Mechanism: Driven by the Electric Dipole (E1) operator, which assumes a direct, first-order interaction between the light wave and the electron.
  • Selection Rules: Must involve a change in parity (Laporte rule) and typically conserve the total electron spin (Δ S = 0). For molecules, the orbital symmetry must allow a dipole moment change.
  • Characteristics: Extremely rapid. Radiative lifetimes of the excited states are very short, usually on the order of nanoseconds
  • FUV Example: The Hydrogen Lyman-alpha transition at 121.6 nm (1s to 2p). In molecules, the Carbon Monoxide (CO) Fourth Positive band system (A1Π to X1Σ+) is a seen in the Venus spectrum. H Lyman-alpha is seen everywhere.

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Quantum mechanics indicates the ‘selection rules’ that explain spectral transitions as ‘allowed’ or ‘forbidden’

FORBIDDEN (photoelectron impact excitation)

  • Mechanism: They rely on higher-order, much weaker interactions, such as Magnetic Dipole (M1) or Electric Quadrupole (E2) operators. They can also occur via weak spin-orbit coupling that breaks the spin rule (called intercombination transitions).
  • Selection Rules: Violate standard E1 rules. For example, they may occur between states of the same parity or involve a change in spin (ΔS ≠ 0).
  • Characteristics: Extremely slow. Excited states are "metastable," with radiative lifetimes lasting from milliseconds to hours. Because they take so long to emit a photon, these transitions are easily "quenched" (de-excited) by collisions in dense gases. They are typically only observed in low-density environments like planetary upper atmospheres or interstellar space.
  • FUV Example: The forbidden atomic Oxygen line ‘[OI] 135.6 nm’ (2p4 3P to 2p3 3s 5So), which is a spin-changing intercombination transition critical for studying Earth's ionosphere.

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Molecular Spectra Arise From Transitions Between Electronic States

  • The N2 Lyman-Birge-Hopfield bands (a 1Πg – X 1Σ+g) are an electric dipole forbidden transition but is allowed for magnetic dipole and electric quadrapole emission.
  • The upper state, a, is excited by photoelectron impact excitation.

LBH

“blue” line

From Meier, 1991

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Atomic Transitions Adequately Understood

The OI 135.6 2p4 3P – 3s 5S is spin forbidden and produces a doublet. – [OI] 1356

The OI 130.4 2p4 3P – 3s 3S transition is allowed and produces a triplet. – OI 1304

Note the green line

And the red line

(also measured by SSUSI)

From Meier, 1991

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How does FUV remote sensing work?

  • Dayside source is EUV/FUV (10 to 130nm) radiation
  • EUV radiation creates photoelectrons that excite emissions via collisions
  • FUV solar lines at 121.nm and 130.4nm can be resonantly scattered in the thermosphere.
  • Two nightside sources
    • Resonant scattering of Lyman alpha from the extended geocorona
    • Radiative recombination – O+ + e creating 130.4nm and 135.6nm emissions

See e.g. Meier, 1991; Paxton and Anderson, 1992

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The General Form of the Radiative Transfer Equation Includes Multiple Scattering

Formal solution of the RT equation

Solving the integral form of the emission rate

where

for photoelectrons

for solar resonant scattering

See e.g. Meier, 1991; Paxton and Anderson, 1992

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Photoelectron Flux Calculations Show the Dependence on the Neutral Atmosphere

contribution from direct photoionization

photoelectron production in the range to due to cascading from higher energy photoelectrons undergoing inelastic collisions

mean pitch angle

Elastic scattering cross section

probability

Inelastic cross section

From Banks and Kockarts

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Signatures map to I/T processes in the Thermosphere

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HI (121.6 nm)

OI (130.4 nm)

OI (135.6 nm)

N2 (LBHs)

Nitric Oxide

N2 (LBHl)

AURORAL ZONE (Disk)

Energetic proton precipitation & boundary

Energy and Flux

Auroral Boundary and amount of column O2 present1

 

Region of electron and (possibly) proton precipitation

O outflow

O Doppler shift

Used with LBHl to form Eo and the ionization rate and conductance information

Hemispheric power

Radar clutter

S/C charging

NO production

Measure of the effective precipitating flux, used with LBHl to form Eo and the ionization rate and conductance information

AURORAL ZONE (Limb)

H profile

O outflow

O outflow

 

 

 

DAYSIDE LIMB

H profiles and escape rate1

Amount of O2 absorption1

O altitude profile

Amount of O2 as seen in absorption

Temperature

NO profile

N2 profile Temperature

DAYSIDE DISK

Column H

Amount of O2 absorption1

Used with LBHs to form O/N2

O/N2 ratio

Solar EUV

NO column density

Solar EUV

NIGHTSIDE LIMB

H profile and escape rate

Ion/ENA precipitation

EDP

HmF2

NmF2

Tplasma

Ion/ENA precipitation characteristic energy

 

Ion/ENA precipitation characteristic energy

NIGHTSIDE DISK

Geocorna and Ion/ENA precipitation

Ion/ENA precipitation

TEC

Ion/ENA precipitation

Ion/ENA precipitation

 

Ion/ENA precipitation

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Inversions vs Assimilation

  • In the years of stone knives and bear skins, we used took remote sensing observations and ‘inverted’ them
  • The ‘shell model’ that yields an altitude dependent quantity (e.g. density) was used for decades
  • However, errors in the measurements, assumptions about all the things you don’t know, and the actual under-constrained inversion itself, present limitations
  • Data assimilation into physics-based models offers a path forward.
  • The measurements described here provide information content that constrains the models.

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Forward Modeling

Inverse Problem

Measurement

Measurement System

Radiative Transfer

Signal Mechanism

Physical Quantity

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NOTE: FUV Remote Sensing Contributes to the Solution – it is NOT the Solution

  • Why do we need to understand the ITM?
  • How do we understand the ITM?
  • What do we gain/learn from that understanding?

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CHALLENGE: What do we focus on and how do we address it?

Choose your own adventure!

Ask me what we could work on together.

I have a ‘hammer’ – everything looks like a ‘nail’ to me.

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Escape the tyranny of the TRL�Let’s build new instruments

  • The basic principles are proven.
  • We can build reliable pointing and scanning mechanisms
  • We can build FUV telescopes – and keep them clean
  • We can build spectrographs to create spectrographic imagers – if we need to
    • There are different ‘mounts’ depending on what you need to control
    • I’ve never had to use freeform optics – wavelength and spatial resolution requirements can be met
  • We can build robust, stable detectors
    • SSUSI and GUVI systems have been flying for over 20 years
  • With experience, you can optimize the solution to the mission requirements
  • With judgement you can establish the multi-dimensional tradespace

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Mission/Instrument Design is Purpose Driven

  • We study geospace because of:
    • The curiosity driven aspects
      • What happens in the upper atmosphere, ionosphere and planetary magnetosphere?
      • What drives these changes?
      • What can we predict about the processes that occur elsewhere in the solar system and how well can we make these predictions?
    • The practical aspects
      • What are the effects of space weather on the performance of technological systems?
      • Are there performance gaps that need to be addressed or that can be exploited?
      • How does space weather affect human life and activities?
      • What is the minimum, irreducible set of measurements and models required in order to operate assuredly in the space environment?

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Simplified Flowdown Used for Tradespace Analysis

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Simplified Flowdown Used for Tradespace Analysis

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A useful solution considers altitude, orbit, measurement requirements, s/c accomodation, budget, schedule, design (imager, spectrograph) .... etc.

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FUV Hyperspectral Imagers Can Provide Operational Support or Science

  • HR-SSUSI is capable of providing products from a wide range of orbits:
    • LEO (heritage)
    • MEO
    • HEO (concepts developed)
    • Cislunar – NRHO Gateway orbits
      • Circumlunar orbits
  • Typical products are:
    • Maps of the nightside ionosphere including ionospheric holes that allow HF frequencies to pass through the ionosphere
    • Maps of the aurora that can be projected via models to provide poleward and equatorward boundary
      • HF propagation
      • Scintillation
      • North/South Pole and polar cap
    • VLEO environment maps including O/N2 ratio and density profiles on limb for drag and anomaly resolution
  • Coverage depends on platform/orbit
  • Typically ~10kg mass, 25W

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We are going back to the moon

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“We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.

President John F. Kennedy

Rice University

12 September 1963

John W. Young on the Moon during Apollo 16 mission Charles M. Duke Jr. took this picture. The LM Orion is on the right. April 21, 1972

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“We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.

President John F. Kennedy

Rice University

12 September 1963

Astronaut John W. Young, commander of the Apollo 16 lunar landing mission, participates in lunar surface extravehicular activity (EVA) training in the Flight Crew Training Building at the Kennedy Space Center (KSC). Young adjusts a training model of a Far Ultraviolet Camera/Spectroscope, an instrument which will be placed on the

Moon during the Apollo 16 EVA. Image # S72-19739

panchromatic FUV electronographic imager

George

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What do you see?

Larry Paxton

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DAY

NIGHT

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The Earth in the FUV: The Subject of this Talk

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Star

Aurora

Star viewed in occultation

Geocoronal hydrogen

Limb profile

Dayglow

Nightglow

Aurora

Nightglow on the limb

Equatorial Arcs

First FUV image of the Earth- taken from the Moon by the Apollo 16 crew

Carruthers and Page, 1972

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The Moon would be a useful vantage point

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First FUV image of the Earth- taken from the Moon by the Apollo 16 crew

Carruthers and Page, 1972

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SSUSI and GUVI: Astonishing data record

GUVI

SSUSI

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I have a flight SSUSI instrument sitting in a dry box. It could be flown

SSUSI-Lite DPU

Also successfully flown High Altitude Balloon test of APL Gamma Ray Neutron Spectrometer

DMSP F20 SSUSI SIS

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The MODULAR DESIGN of the Scanning Imaging Spectrograph (SIS) readily enables component-level and end-to-end testing and evaluation.

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Scan Mirror

Cover, Side

SIS Cover (shown without pin puller)

Detector�(not shown)

Grating (located inside housing)

Telescope Housing

Scan Motor/Gear Box and Adapter

Slit Mech�(internal)

SIS Main Housing

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Scan Mirror Shaft and Counterweight

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Scanning Imaging Spectrograph – Cross Track Scanner

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GUVI and SSUSI see about 1.5 hours on each side of the s/c from LEO

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O/N2 is a signature of the bottomside ionosphere

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O/N2 reference is point where N2 column = 1017 cm2

or about 135km-165km depending on solar zenith angle, exospheric temperature, etc.

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November 2003 Storm

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VLEO – VERY LOW EARTH ORBIT�The new frontier that sustains the outward journey

  • VLEO operations (below 300km) are challenging because, without propulsion, orbital lifetimes are very short (less than a year)
  • VLEO operations enable:
    • Larger payload to orbit
      • Starlink Feb 2022 – a cautionary tale
    • Smaller Earth remote sensing sensors
    • Denser networks
    • Debris management
    • Economic advantage as well as security capability
  • To take full advantage of this environment, we have to be able to understand and predict the flight envelope

https://mashable.com/video/spacex-satellites-burn-up-atmosphere-space-storm

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Interesting problem: what causes perturbations in the bottomside?

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bottomside ionosphere

APL is a coin-operated machine – I’m always looking for new opportunities

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Why should you care about O/N2?

  • O/N2 is a column density measurement mapped to the ratio of the column O above the point where the N2 column density reaches 1017 cm-2
  • In the lower thermosphere loss to N2 and O2 has lifetimes from less than 1 sec (120km) to tens of seconds

figure from Justin Yonker

O+

For medium high solar activity (F10.7=170), Figure 5.1 follows the chain of events beginning with the deposition of solar energy, through the ion-neutral chemical cascade, eventually resulting in the production and loss of NO (Yonker 2013). As the thermospheric species with the second highest ionization energy, N+ is very reactive and lies near the top of this chain.

Most of the NO GUVI emission comes from the NO density peak near 106 km (Barth and Bailey 2004). At these altitudes, N+ is lost rapidly (chemical lifetime <1 sec) and primarily to O2.

There are three product channels

 N+ + O2 → NO + O+ R1 (50%)

→ NO+ + O R2 (40%)

→ N(2D) + O2+ R3 (10%)

with 50% of the reaction leading to N(2D) (the main NO production source

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O/N2 is a proxy for changes in TEC and hmF2

  • In the F-region:
  • Below ~250 km: O⁺ lifetime = seconds
  • 250–300 km: minutes
  • >350 km: hours
  • Loss of O+ is controlled almost entirely by N₂ and O₂ densities.
  • Production of O+ is controlled by photoionization

 

Signal responds instantly to rapid changes in the bottomside

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Another simple idea: Where is hmF2?

  •  

This indicates that ingesting O/N2 is a messenger for changes in hmF2 – important in an assimilative model

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Global access provided by small LEO sensor

  • We can look at whether there are large gradients in the signal
  • How does the FUV signal relate to TEC?
  • One can derive a simple relationship by integrating a Chapman ionosphere for TEC and radiance:

 

 

 

 

If there are small depletions in n(z) at the bottomside (nmF2 stays constant) then

changes in intensity are directly related to changes in TEC

dTEC driven by changes in O/N2 will be below the F2 peak

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January 2021 Sudden Stratospheric Warming Event�

The polar vortex began showing signs of disturbance in late December 2020, and by around January 5–6, 2021, a full vortex displacement had occurred — the vortex was shoved off the pole toward Eurasia rather than splitting cleanly in two.

Stratospheric temperatures over the Arctic rose sharply while zonal winds at 10 hPa reversed to easterlies, meeting the formal definition of a major SSW.

It was one of the stronger events of the prior decade in terms of how rapidly and thoroughly the vortex was disrupted.

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Movie to follow provided by Sebastijan Mrak

night

day

day

Night : we use ‘1356’ the atomic oxygen 135.6nm emission feature arising from O+ recombination

Day : we use the ‘O/N2 ratio’ (the ratio of the O 135.6 nm emission to the N2 LBH band emission)

(lots of details here for the experts in the room to savor)

teminator

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A single GUVI orbit

We usually have 4 SSUSI/GUVIs collecting data

BLUE indicates NIGHT

RED indicates DAY

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Nightside O 135.6nm observations seem to be broadly consistent with a wavelength of 500km and an amplitude of ±0.2 TECU

Detailed analysis will be performed.

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We can map small (and large) scale changes in dTEC

Chemical lifetime in the bottomside is 10s to 100s of seconds

1R ~ 1 TECU

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Chemical lifetime in the bottomside is 10s to 100s of seconds

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  • Generally similar – next steps are to do OSEs using models that self-consistently determine the intensity ratio and deduce a relationship between O/N2 intensity ratio and hmF2
  • How do we validate wave models?
  • The interaction of the waves with the background I/T creates a signature that would test the net effect.

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COST has been a barrier

  • Launch costs, especially for LEO missions, have fallen.
  • Instrument and mission costs have not.
  • Will NASA cost models, QA and best practices become the new barrier?
  • The NICM model uses a database of NASA managed programs to establish cost and schedule estimates

https://www.nasa.gov/ocfo/nasa-instrument-cost-model-nicm/

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Our community could do a ITM QB50

  • GOAL: make low-cost, unique measurements between 300-400km
  • QB50 was a European Union mission consisting of 50 cubesats built by participants
    • 36 2U and 1 3U were built
    • Participation from 23 countries
    • Participants contributed funds - $4M
  • String of pearls configuration to measure I/T properties
  • Buses built to ‘industrial standards’

https://cordis.europa.eu/project/id/284427

https://www.eoportal.org/satellite-missions/iss-nanoracks-qb50#eop-quick-facts-section

https://www.nasa.gov/mission/station/research-explorer/investigation/?#id=7479

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A Lesson on the Journey to the Abundance Mindset

  • Once I saw this guy on a bridge about to jump. I said, "Don't do it!" He said, "Nobody loves me." I said, "God loves you. Do you believe in God?"

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https://www.youtube.com/watch?v=X09_sw_vc6w

https://www.theguardian.com/stage/2005/sep/29/comedy.religion

Emo Phillips

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A Lesson Along the Journey to the Abundance Mindset

  • Once I saw this guy on a bridge about to jump. I said, "Don't do it!" He said, "Nobody loves me." I said, "God loves you. Do you believe in God?"
  • He said, "Yes." I said, "Are you a Christian or a Jew?" He said, "A Christian." I said, "Me, too! Protestant or Catholic?" He said, "Protestant." I said, "Me, too! What franchise?" He said, "Baptist." I said, "Me, too! Northern Baptist or Southern Baptist?" He said, "Northern Baptist." I said, "Me, too! Northern Conservative Baptist or Northern Liberal Baptist?"
  • He said, "Northern Conservative Baptist." I said, "Me, too! Northern Conservative Baptist Great Lakes Region, or Northern Conservative Baptist Eastern Region?" He said, "Northern Conservative Baptist Great Lakes Region." I said, "Me, too!"
  • Northern Conservative Baptist Great Lakes Region Council of 1879, or Northern Conservative Baptist Great Lakes Region Council of 1912?"
  • He said, "Northern Conservative Baptist Great Lakes Region Council of 1912.”

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https://www.youtube.com/watch?v=X09_sw_vc6w

https://www.theguardian.com/stage/2005/sep/29/comedy.religion

Emo Phillips

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A Lesson Along the Journey to the Abundance Mindset

  • I said, "Die, heretic!" And I pushed him over.

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https://www.youtube.com/watch?v=X09_sw_vc6w

https://www.theguardian.com/stage/2005/sep/29/comedy.religion

Emo Phillips

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What do heroes look like?�Everyone that made DYNAMIC happen is a hero

  • Three groups just completed a journey that started 15 years ago
    • Two teams were not selected.
    • No ‘losers’ – they advanced our understanding
  • In 2011 and 2012 the Decadal Survey recommended a ‘DYNAMIC reference mission’
    • CATE cost $480M (my recollection)
  • The 2013 NASA Roadmap showed that DYNAMIC was not likely to happen under the Decadal assumptions.
  • The fact that 4 teams were willing to submit Step 1 proposals indicated to NASA that the community was able to address the science called out in the previous Decadal and endorsed in the DS2024.

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Practice the abundance mindset!

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What do heroes look like?

  • Three groups just completed a journey that started 15 years ago
  • In 2011 and 2012 the Decadal Survey recommended a ‘DYNAMIC reference mission’
    • CATE cost $480M (my recollection)
  • The 2013 NASA Roadmap showed that DYNAMIC was not likely to happen under the Decadal assumptions.
  • Two teams were not selected.
  • One was.
  • No ‘losers’ – they advanced our understanding.
  • The fact that 4 teams were willing to submit Step 1 proposals indicated to NASA that the community was able to address the science called out in the previous Decadal and endorsed in the DS2024.

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This is our call to action – we need to support GDC-Trailblazer and DAPHNE

Whether we see an immediate return or not

There may be others that will seize upon any remarks that experts in our community make as reasons not to prioritize funding of DYNAMIC or GDC-Trailblazer in the PBR

Dao and Stoicism (many others) tell us to accept what we cannot change – peace lies within

Let’s try to live in an ‘abundance mindset’

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Let’s shape the future - together

  • Imagine if you had the answer to the fundamental questions we’ve talked about – what would this enable?
  • Envision the future
    • How do we get there?
    • What do we have to know?
    • Where do we have to go?
    • Who do we have to connect with to build that future?
  • We are all passengers on a one-way time machines - we move into the future one day at a time.
    • We can see the past in our collective experience and learn from that – some see back further than others!
    • We can send a message into the future by what we do for our community

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A sincere thank you to you all

  • “When I was young, I had to choose between the life of being and the life of doing. And I leapt at the latter like a trout to a fly. But each deed you do, each act, binds you to itself and to its consequences, and makes you act again and yet again. Then very seldom do you come upon a space, a time like this, between act and act, when you may stop and simply be. Or wonder who, after all, you are.”�
  • ― Ursula K. Le Guin, The Farthest Shore

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