The Solar Group is ~30 people working to better understand the Sun and the sources of its variability.

There are several projects including one on the ground, one in space, and one in development for space.

The Wilcox Solar Observatory at Stanford has been operating since 1975

HOP

HEB

HMI & AIA Joint Science Operations Center Architecture – The Stanford Solar Group will provide the ground data system for both HMI and Lockheed-Martin’s AIA instrument on SDO – Together these represent 95% of the SDO data, about 1.4TBytes/day

Catalog

Primary Archive

HMI & AIAOperations

House-keeping

Database

MOCDDS

Redundant Data

Capture System

30-DayArchive

OffsiteArchive

OfflineArchive

HMI JSOC Pipeline Processing System

DataExport& WebService

Stanford

LMSAL

High-LevelData Import

AIA AnalysisSystem

LM-Local Archive

QuicklookViewing

housekeeping GSFCWhite Sands

World

Science TeamForecast Centers

EPOPublic

We use the web as a tool for ourselves as well as collaborators and the general publicOur home page has links to our various projects: Observational Solar Physics at Stanford University

Philip Scherrer

MDI observations have enabled better understanding of the interior structure of the Sun. The techniques of local helioseismology have been developed with MDI data and led to plans for SDO/HMI.

MDI was designed and build as part of an ongoing collaboration with the solar group at Lockheed-Martin Solar and Astrophysics Laboratory in Palo Alto.

The Michelson Doppler Imager instrument of the Stanford Solar Oscillations Investigation onboard the ESA/NASA Solar and Heliospheric Observatory has been operating since December 1995

MDIOptics

Electronics

Sound speed beneath a sunspot Internal rotationFar-side of the Sun magnetic fields

WSO is dedicated to long-term daily observations of the large scale magnetic fields. Data are used for analyses and correlative studies worldwide.

All WSO data is freely available.

We are interested in developing collaborations for studies of the Sun and Space Weather using WSO, MDI, and shortly HMI observations. All data from these projects is freely available via the web. There are more interesting studies to do with this data than can be accomplished by the just teams at Stanford and our Co-Investigators and other collaborators. Problems that need significant data volumes can be pre-processed at Stanford so the computing requirements for leading-edge helioseismology need not be a deterrent to new investigations.

The HMI team includes researchers from 23 institutions. Additional collaborations are welcome.The Helioseismic and Magnetic Imager

for the Solar Dynamics Observatoryof the Living With a Star programof the Sun Earth Connection Divisionof the NASA Office of Space Science

The primary goal of HMI is to study the origin of solar variability and to characterize and understand the Sun’s interior and the various components of magnetic activity.

Launch in April 2008

HMISDOLWSSEC

NASA

Observational Solar Physics Group at Hansen Experimental Physics Laboratory atStanford University

Faculty: Philip Scherrer Physics & HEPLAdministrative: Romeo Durscher Admin Assistant (financial) Margaret Stehle Admin. Assistant (documents)MDI Data and Operations: Jim Aloise System Software Keh-Cheng Chu Scientific Software Sarah Gregory At GSFC, MDI Observer Jeneen Sommers Science & Engineering Assoc. Hao Thai Science & Engineering Assoc. Brian Roberts Computer OperationsHMI Development, VSO Development Rock Bush Sr. Research Scientist Rasmus Munk Larsen Research Scientist Karen Tian Research ScientistSOI (MDI Helioseismology and motions) Analysis: Tom Duvall, Jr. NASA visiting scientist Alexander Kosovichev Sr. Research Scientist Jesper Schou Sr. Research Scientist Sebastian Couvidat Research Scientist Laurent Gizon Research Scientist Junwei Zhao Research Scientist Rick Bogart Sr. Research Scientist John Beck Research Scientist Shravan Mukunda Graduate Student – EE Shalini Krishnamurthy Graduate Student – SCCM Christina Green Graduate Student – SCCM Majid Modarresi Graduate Student – SCCM WSO, Space Weather, Corona, MDI magnetic field: J. Todd Hoeksema Sr. Research Scientist Taeil Bai Sr. Research Scientist Xue Pu Zhao Sr. Research Scientist Yang Liu Sr. Research Scientist Elena Benevolenskaya Research Scientist Keiji Hayashi Research Scientist Bala Poduval Research Scientist Paul Boerner Graduate Student - PhysicsEducation and Public Outreach: Deborah Scherrer E/PO Coordinator Paul Mortfield Consultant

OP Structure

Telescope

Front Window

Front Door

Vents

Support Legs (6)

Polarization Selector

Focus/Calibration Wheels

Active Mirror

Limb B/S

Alignment Mech

Oven Structure

Michelson Interf.

Lyot Filter

Shutters

Connector Panel

CEBs

Detector(Vector)

Fold MirrorFocal Plane B/S

Detector(Doppler)

Limb Sensor

Overview of the Helioseismic and Magnetic Imager Investigation The primary scientific objectives of the Helioseismic and Magnetic Imager (HMI)

investigation are to improve understanding of the interior sources and mechanisms of solar variability and the relationship of these internal physical processes to surface magnetic field structure and activity. The HMI instrument will make measurements of the dynamic motion of the solar photosphere on global and local solar scales to study solar surface oscillations and will make similarly scaled measurements of the polarization in a spectral line to study all three components of the photospheric magnetic field. HMI observations will help to establish the relationships between the internal solar dynamics and related magnetic activity.  

Specific scientific objectives of the HMI investigation are to measure and study: 

1. Convection-zone dynamics and the solar dynamo; 2. Origin and evolution of sunspots, active regions and complexes of activity; 3. Sources and drivers of solar magnetic activity and disturbances; 4. Links between the internal processes and dynamics of the corona and heliosphere; 5. Precursors of solar disturbances for space-weather forecasts.  

The HMI instrument will produce measurements in the form of filtergrams in a set of polarizations and spectral line positions at a regular cadence for the duration of the mission that meet these basic requirements:

 Full-disk velocity and line-of-sight magnetic flux images with 1 arc-sec resolution every 50

seconds. Full-disk vector magnetic images of the solar magnetic field with 1 arc-sec resolution every

10 minutes.   The HMI investigation will provide sufficient computing capability to convert these raw

filtergram measurements into a set of observables and derived data products required for the HMI science objectives. The primary observables (Dopplergrams, longitudinal and vector magnetograms, and continuum intensity images) will be constructed from the raw filtergrams and will be made available at full resolution and cadence.  Other derived products such as subsurface flow maps, far-side activity maps, and coronal and solar wind models that require longer sequences of observations will be produced and made available. All HMI data products will be made available to all interested investigators.

 

SDO will carry The Atmospheric Imaging Array provided by Lockheed Martin Solar and Astrophysics Lab and the EUV Variability Experiment provided by the University of Colorado in addition to HMI.

HMI Optics Package

The web provides access to many of our E/PO activities. See also the poster by John Beck

WSO Magnetic FieldSynoptic maps of observed photospheric field have been made since 1976.

Inferred coronal field maps are available for each Carrington rotation. These predict the polarity structure in the heliosphere.

Solar polar field strength vs. time