AstroGrid Solar/STP planning AstroGrid Solar/STP planning meetingmeeting

Agenda:Agenda:

• Helioscope

• Preparing for Solar-B

• Time-series viewing application

• IVOA and time series

A PPARC funded project

Start time

End time

Helioscope

SolarSTPCataloguesSTP/time lagged

Retrieving solar system data: Helioscope

Helioscope - Lite

• Returns FITS for solar and flat files in ‘native’ format for time series (ASCII, CDF…)

• Data from 2 main archives : VSO (Virtual Solar Observatory) and CDAW space physics archive using: -API provided by VSO http://vso.nascom.nasa.gov/API/ -SOAP interface to CDAW http://cdaweb.gsfc.nasa.gov/WebServices/

• Note: at this stage requests are not in standard form, but hard coded

• Short term solution – users easily get data – typically already have software dealing with specific format

Astroscope / Helioscope

• Astroscope is based on SIAP (Simple Image Access Protocol):

POS, SIZE are mandatory parameters:

EG: http://myimages.org/cgi-bin/VOimg?POS=18.567,-30.45&SIZE=0.01

• It’s convoluted to use POS, SIZE for Solar System objects.

• Define a Simple Time-range Access Protocol that returns a votable listing files (either images or time series) within specified time range

Mandatory parameters: START, END, FORMAT

• Ok also for Astronomy time based queries, eg by having optional parameters POS, SIZE. Other optional parameter could be INSTRUMENT

Helioscope - votable

• Returns time series data in a common format - votable

• DSA plugin that converts from ASCII, CDF to votable. If request spans more than 1 flat file, joins time series into a single votable

• Provide a framework where the data holders can specify what the local format is, and how translation to Votable should be done.

• NOTE: Votable does not have a url pointing to a data file any longer- the votable contains the data points themselves!

Identifying time series column in Votable

• In the votable containing time series data, the time field needs to be identified.

• 2 possible ways: (1) Introducing a datetime type in votable or (2) using a combination of UCD and Unit attributes.

• These are some current valid UCD words related to time: (from: http://www.ivoa.net/Documents/latest/UCDlist.html )

Q | time                       | Time Q | time.event                 | Duration of an event or phenomenon Q | time.event.end             | End time of event or phenomenon Q | time.event.start           | Start time of event or phenomenon Q | time.obs                   | Observation on-time, duration Q | time.obs.end               | End time of observation Q | time.obs.start             | Start time of observation Q | time.resolution            | Time resolution Q | time.scale                 | Timescale

Viewing time series

• TOPCAT required features:

-automatic conversion from ISO time format to numeric values (column identified by UCD + Unit)

-stackplot capability

Summary: Helioscope-IVOA

• Work towards Helioscope-lite has started

• IVOA work: time UCDs, Simple Time-Range Access Protocol

• Define a way to identify time column in votable

• DSA plugin / way for data centers to provide time series data as VOT

• Topcat support for time series

CTIP model – mode A

• Available to all AG users as parametrised workflow

• Mode B – will allow automatic fetching of Kp and F10.7 from RAL – working – being fine tuned before release

CTIP model – mode A – output & documentation

• Future CTIP developments: convection maps from Superdarn as input – mode C,D,…

• Documentation on output files – example plotting programs

STP science case workflow

STP science case results