JUSTIN KASPER (HARVARD-SMITHSONIAN)GEOFF REEVES (LANL)

NASA HELIOPHYSICS TOWN HALL MEETING

MAY 19, 2008

Summary of Major Scientific Advancements since 2006

Roadmap

Purpose and outline2

We are gathering the major scientific advances in heliophysics that have occurred since the last roadmap

Goals Identify the most compelling heliophysics so we are able to

present the strongest case possible in our revised roadmap Identify observational gaps prohibiting discovery Determine if changes need to be made in Research Focus

Area organizational structureThis presentation

Not going to try and review all Heliophysics accomplishments since 2006!

Describe the review process Solicit input Present several examples Explain the splinter session goals

Heliophysics Research Elements in 2005

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Heliophysics sorted into Research Focus Areas (RFAs) Full review of the RFAs will be presented this

afternoon by Lynn Kistler, so just a summary here F: Open the Frontier to Space Environment Prediction

Magnetic reconnection, particle acceleration, dynamos H: Understand the Nature of Our Home in Space

Disturbances, solar input and climate J: Safeguard the Journey

Radiation extremes, early warning

Assessment Strategy - Input4

Recent discoveries and recently appreciated work

Observations, models, theory Need more input on models and theory

Sources of input Senior Review

Each mission requested to submit summary of recent accomplishments

Literature reviews Committee knowledge Community input

Created email address: helio.progress@gmail.com

Assessment Strategy - Analysis5

Created spreadsheet to track accomplishments Sort by Research Focus Area For each result

Short description Identify primary topic addressed by result Secondary topics addressed Contributing missions (include theory and model as

“missions”) References

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Highlights and Emerging Themes7

Discoveries at the boundaries of the heliosphere

Magnetic reconnectionMulti-spacecraft research

Discoveries at the boundaries of the heliosphere

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Three examples of recent discoveries Voyager spacecraft crossed the termination shock AIM sees formation of H2O regions over broad range in altitude SOHO produces statistical evidence of g-modes at 3-sigma level

Results, new questions

Initial AIM observations of Polar Mesopheric Clouds (PMCs)

9CIPS image on July 10, 2007 showing an ice void

When the AIM observatory was launched on April 25, 2007, the science focus was on a thin (~1.5 km thick) visible ice cloud layer centered at ~ 83 km above the earth surface known as PMCs. What was found in the first season of observations was a previously suspected but never before seen population of very small ice particles that exist over a much broader altitude range.

Large regions virtually devoid of ice suggest that the mesosphere may share some of the same dynamical processes that are responsible for weather near the surface.

The Termination Shock10

Voyager 1 crossed termination shock in December 2006

Anomalous cosmic ray source not seen!

Voyager 2 crossed in August of 2007

Termination shock is deformed

Plasma heating is 10x low and the outflow is 2x too fast!

Implications Radiation plays significant

role in termination shock physics

Voyager 2 will cross the heliopause within a decade

IBEX will have a strong energetic particle population to detect

A Statistical Detection of G-modes11

Helioseismology is the inference of solar interior properties through the observation of oscillations on the solar surface Travelling waves probe sound speed, temperature, velocity at different

depths G-modes have never been seen, but if detected would probe the solar core

Global Oscillation at Low Frequency (GOLF) instrument on SOHO Instead of looking for an individual ripple, they looked for the signature of

the cumulative effect of a large number of these ripples separated by about 24 minutes.

They combined ten years of data from GOLF and then searched for any hint of the signal at 24 minutes. They found it. “We must be cautious but if this detection is confirmed, it will open a brand new way to study the Sun’s core,” says García.

Until now, the rotation rate of the solar core was uncertain. If the GOLF detection is confirmed, it will show that the solar core is definitely rotating faster than the surface. important constraint for investigating how the entire Solar System formed because it represents the hub of rotation for the interstellar cloud that

eventually formed the Sun and all the planets, asteroids, etc., around it

Magnetic reconnection12

The 2005 Roadmap called for the discovery of magnetic reconnection across the heliosphere

Reconnection is ubiquitous: Within the solar corona (flares and coronal holes) Interplanetary space (CMEs and quiet solar wind) Magnetosphere

Coronal Magnetic Reconnection13

Magnetospheric Reconnection14

Comparison between the observed (left panel) and simulated (right panel) plasma and field profiles of Rumba (Cluster-1) crossing the reconnection electron jet close to a reconnection site.

January 2003, the four Cluster satellites were crossing the magnetosheath when they encountered an electron diffusion region.

Cluster confirmed the existence of an elongated electron diffusion region

The length observed by Cluster is 3000 km, or 300 times longer than the earlier theoretical expectations

T. Phan (Berkeley); M. Shay (Delaware)

2D projection

Br

Vr

Bt

Vt

Bn

Vn

Reconnection Exhausts in the Solar Wind

J. Gosling (LANL)

Statistical Studies of IP Reconnection16

J. Gosling (LANL)

Rate vs solar wind conditions No energetic particles!

Multispacecraft studies17

Reconnection exhaust observed by five spacecraft Reconnection exhaust is very stable and geometrically simple Gosling et al. (2007)

Halloween 2003 CMEs observed by entire Heliophysics Great Observatory Are there equivalent solar minimum heliosphere observations?

Strong correlation between spectra of hard x-ray bursts (RHESSI) and interplanetary electrons (Wind) indicating common source

First stereo STEREO observations Filaments Coronal Mass Ejections Co-rotating interaction regions

Food for thought18

Snapshot of current study19

10:30 – 12:30 TODAY

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Format of the First Splinter Session

The First Splinter21

The purpose of the first splinter group is to receive input from the community on the following questions: In your view, what is the most compelling and enabling

science that will advance Heliophysics in the next 5-10 years?

In the next 10-20 years?

Your participation will help us: Lead with the most compelling science Identify any game-changing recent results develop better ways to portray our Heliophysics goals

and long-term strategy.

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We will divide the main room into three smaller rooms, and meet around the tables for two one-hour sessions.

In the first hour we will discuss what our short term scientific goals should be, based on recent results and our current understanding of the Heliosphere.

In the second hour we will examine our longer-term scientific strategy and develop ways to portray this strategy.

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Mission timelines portray

Summary25

Help us identify any missing pieces to this story Spacecraft not under senior review Guest Investigator and other independent research Are advances in some fields not captured by this

process (aerobraking, exoplanets…)

Resources Electronic copy of spreadsheet available Comments and suggestions greatly appreciated

Helio.progress@gmail.com