# Presentation: 427943

## The Virtual HeliosphericObservatoryVHO

## The VHO Team

**The VHO Team**

- Adam Szabo (lead)	NASA/GSFC
- Andrew Davis		Caltech
- George Ho		JHU/APL
- Justin Kasper		MIT
- Jan Merka		U. Maryland, Baltimore County
- Thomas Narock		L3 Communications
- Jim Raines		U. Michigan
- Kathryn Rash		NASA/GSFC
- D. Aaron Roberts		NASA/GSFC
- Peter Schroeder		U. California, Berkeley
- Jon Vandegriff		JHU/APL
*Collaborators*:
- Paul Gazis	SETI Institute		Richard Keller	NASA/ARC
- Neal Hurlburt	Lockheed Martin SAL	Shawn Wolfe	NASA/ARC

*Team membership is dynamic as new data products and services will be added.*

## Slide 3

## VHO Services

-  No data flow through the VHO middleware!   *Our Role*: 	Connecting data to independent services.		Enable services not develop them ourselves.
-  Ability to search for services
-  Metadata of service description
-  Ability to search for data related IDL routines (HelioSoft)
-  Metadata of routines
-  Mission independent VHO Data Environment

## VHO Architecture

-  Lightweight middleware with search capability.
-  Common metadata description of products and   services based on SPASE dictionary.
-  Data exchange and synchronization mechanism.
-  Minimum possible requirements on data providers.
-  Low cost extensible system deployed in phases.

## VHO Development Phases (1)L1 Data Environment

**VHO Development Phases (1)****L1 Data Environment**

-  L1 data sets made  web accessible.
-  Data products  described in SPASE  compliant metadata  format.
-  Data exchange  synchronization  established between  data providers.

## VHO Development Phases (2)Basic VHO

**VHO Development Phases (2)****Basic VHO**

-  Middleware with both  Web and API user  interfaces.
-  All middleware  static and dynamic  metadata products  developed.
-  Public access to  software tools with  metadata.

## VHO Metadata

**Static Metadata** (requiring no or infrequent updates)
-  Product Metadata  – Complete description of data content.
-  Registry Metadata – Data service information
-  Service Metadata  – Complete description of added-value                                    data processing services.
-  VHO Metadata      –  WSDL description of VHO functionality.

**Dynamic Metadata**   (requiring daily updates)
-  Availability – Current range of available data.
-  Software    – Current list of available software tools.

## VHO Web Interface

- Data can be searched for by the following ways:

- Time
-  Date/Time
-  Bartel/Carrington Rot.
- S/C Location
-  GSE/GSM/HGI coord.
-  Region name
- Measurement Type
-  e.g., magnetic field,  thermal plasma,  energetic particles

- Selecttime period

- Selectregion of interest

- Optionallyrefine S/Cselection

## VHO API

**VHO API**

-  IDL VM Demo  software
-  Library
-  Perl
-  Java
-  CoSEC
-  IDL (soon)

- The VHO API will allow access to all VHO functions.

## VHO Development Phases (3)Full VHO

**VHO Development Phases (3)****Full VHO**

-  Connection  to processing  services.
-  Connection  to other VxOs

## Community Input

-  Large, diverse and dynamic team membership.
-  Submit recommendations via our web page:		_[http://vho.nasa.gov](http://vho.nasa.gov/)_
-  Ask users to prioritize upcoming feature additions.
-  Web statistics
-  Bi-annual VHO meetings at AGU conferences.

## VxO Interaction

-  Our first focus will be on interacting with VSO.
-  Will not attempt to recreate full VSO web interface. Rather,  a heliosphere centric view will be provided. API will have  access to most VSO capabilities.
-  WSDL description of VHO services.
-  Passing dynamic metadata between VxOs would allow   the execution of complex queries.

## BACKUP

## Data Provider Requirements

-  The VHO is designed to minimize requirements on    data providers. The VHO will work with any currently   available data formats or services.
-  The VHO team will assist data providers in the one-time   generation of the detailed product metadata.
-  Data providers will have to allow access to their products.  The preferred mechanism will be via the VHO team provided  SOAP interface for local queries. But implementing this  SOAP interface will not be mendatory.
-  Data providers will have to allow the VHO synchronization  routines to run on their machine providing metadata updates.

## Data Exchange Synchronization

**Data Exchange Synchronization**

- Synchronized copy of data from similar instrument used to improve calibration.

- Synchronized copies of various other data products used to generate merged or added value new product.