Living With a Star (LWS) and the Vision for Exploration

LWS Mission Goal: Develop the scientific understanding necessary to effectively address those aspects of the connected Sun Earth system that directly affect life and society.

What are implications of LWS for the Vision for Exploration?

• NASA’s Vision for Space Exploration has focused efforts on human and robotic investigation to answer such questions as: How did our solar system form? How and where did life begin? and How far can humankind extend its reach? (The New Age of Exploration, NASA Publication, February 2005).

• From inception in 2001 (LWS Science Architecture Team), the LWS adopted as one of four major goals: “ Extend our knowledge and understanding gained in this program to explore extreme solar-terrestrial environments and implications for life and habitability beyond Earth”.

LWS from inception has been closely aligned with Exploration Vision Goals

Prediction Requires Understanding.Understanding Requires a System-Wide Approach

How do we link what happens at the Sun with the planetary response?

STEREO, SDO, Solar Probe

ACE, STEREO, Solar Sentinels

LWS Geospace

Observing the Observing the SourceSource

Active RegionsActive Regions

X-ray, EUV, UVX-ray, EUV, UV

Energetic Energetic ParticlesParticles

Solar WindSolar Wind

Monitoring Monitoring PropagationPropagation

Solar Energetic Solar Energetic ParticlesParticles

Coronal Mass Coronal Mass InjectionsInjections

I. P. ShocksI. P. Shocks

Understanding planetary Understanding planetary responsesresponses

Radiation ProcessesRadiation Processes

Space / Atmosphere Space / Atmosphere InteractionsInteractions

Ionosphere-Upper Ionosphere-Upper AtmosphereAtmosphere

Measure at EarthMeasure at Earth

Model at MarsModel at Mars

LWS focus is on defining environments within which Exploration assets must be engineered

• Key goal of the Vision is to understand the space environment and needed countermeasures to prepare for manned exploration missions (Exploration Systems, Program Overview, 2004).– Key commission findings (Packard, 1985) call for:

• Technologies to lower system costs and increase performance.

• Technology maturation before engineering & systems development.

– Key reports (DSB/AFSAB; Young, 2000) emphasize that requirements definition and control are dominant drivers of cost, schedule, and risk in space systems development.

• To achieve this key goal, we require a robust research program to generate accurate models that predict the space weather environment throughout the whole accessible solar system, including the Earth-Moon-Mars system

Mars: Modeled Space Environment

LWS Geospace leads the way for understanding other planetary responses to solar variability

• LWS Geospace (Ionosphere-Thermosphere Storm Probes) yield detailed understanding of how Earth’s upper atmosphere & ionosphere respond to solar & interplanetary variations.

• Atmospheric & ionospheric responses to solar variability at other planets (Mars) are important issues for engineering Exploration systems (e. g. for communications, vehicle-atmosphere interactions, etc.)

• Only within Earth’s ionosphere-thermosphere region can sufficient resources be flown to collect the comprehensive measurements necessary to develop complex atmospheric response models.

• These models developed at Earth are tested for Mars parameters and can be validated using the much more limited datasets from Mars.

Earth’s Ionosphere/Thermosphere Processes

Measure at Earth, Model at Mars• Observations of parameters in the Earth’s ionosphere-thermosphere region

(density, winds and composition) are critical for the generation of improved atmospheric models.

• Conditions within the Martian atmosphere resemble those within the Earth’s thermosphere, thus Global Circulation Models at Earth can be adapted for Mars.

• Accurate models are crucial for the forthcoming exploration missions to Mars which will employ atmospheric aero-capture and aero-braking.

• LWS/Geospace will provide the understanding necessary to model the atmospheres of Mars and the other planets in our solar system

MarsMTGCM Odyssey Case (Ls = 270):

Densities at 110 km

EarthTGCM (Day = 100):Densities at 110 km

• LWS Geospace (Radiation Belt Storm Probes) provide detailed understanding and updated models of the near Earth radiation environment in response to solar variability.

• These parameters will be crucial for near-Earth test missions, on-orbit construction projects, space-based communication systems, and Earth orbiting infrastructure and operations needed to support manned missions to the Moon, Mars and beyond.

LWS Geospace defines radiation design parameters and hazards for Exploration development

• Gross uncertainties (factor of 10) in present radiation models that are 10-20 years old lead to costly over-design and decreased capabilities from risk aversion.

• Improved specification, predictive understanding, and models from LWS Geospace yield reduced costs, reduced risk, and increased capabilities for Exploration development.

SpaceStationL-shells

Interplanetary ShockDriven Enhancements

Time

Posi

tion

Earth Orbit

Radiation Intensity

• The new radiation model in geosynchronous orbit demonstrates huge deficiencies in old models.

• New models are not available in most critical regions.

• Recent findings show the importance of the low energy component for space engineering.

• Use of accurate models leads to reduced cost and risk for Exploration.

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AE8max Electrons/ sec keV cm2AE8max low-energy extrapolationPOLE cas moyenPOLE low-energy extrapolation

Ele

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sec

keV

cm

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Electron Energy, keV

GEO

We Need New Models Now

New model

Old model

Geosynchronous Orbit

• LWS/Geospace uses a system-wide approach to achieve predictive understanding of Exploration environments.

• LWS/Geospace-derived information is needed now for designing Exploration systems and infrastructure.

• Modeling responses of planets like Mars to solar variability requires the comprehensive measurements & understanding of planetary responses achievable only at Earth.

LWS/Geospace Supports NASA’s Vision for Space Exploration

LWS/Geospace allows Exploration missions to be implemented more cheaply, with less risk, and better technology selection. Exploration missions will fly sooner and be better.

This information is needed now, well in advance of missions that directly support the manned Exploration missions to the Moon, Mars and beyond.

LWS/Geospace Supports NASA’s Vision for Space Exploration

BACKUP

LWS Science aligned with Exploration Science that addresses life and origins of solar system

• Magnetic fields play central to roles in moderating molecular cloud core collapse and bi-polar jets formation central to the shedding of angular momentum.

• Electromagnetic interactions between dust particles possibly central to the initial growth of planetary building blocks.

• Magnetic fields possibly key to maintaining planetary atmospheres and moderating mutations in the evolution of life.

• Space radiation is both inhibiting and an enabling (energy source) in consideration of whether life has formed (e. g. within Europa).

• Solar variability in early solar system history possibly played key role in sweeping volatiles out of the region of the terrestrial planets.

• It is now believed that solar variability has some influence on Earth weather, and thus probably its climate. What role do such effects have on past habitability? Proto-Star

Bi-polar jets