Title: Searching for Data with the Virtual ITM Observatory
1Searching for Data with the Virtual ITM
Observatory
- D. Morrison, M. Weiss, R. Daley, L. Immer, C.
Colclough, R. Holder, J. Jen, D. Patrone, M.
Hashemian, P. Meckel, M. Potter, R. Barnes, S.
Nylund, J.-H. Yee, and E. Talaat - (Johns Hopkins University, Applied Physics
Laboratory 11100 Johns Hopkins Rd. Laurel MD,
20723 240-228-4172) - J. Russell
- (Hampton University)
- R. Heelis
- (Univ. Texas at Dallas)
- J. Kozyra
- (Univ. of Michigan)
- D. Bilitza, R. McGuire, and R. Candey
- (NASA Goddard Spaceflight Center)
- P. Fox
- (HAO/NCAR)
2Primary Tasks for Mission Data Center or Virtual
Observatory
- (1) describe their data holdings and resources
- (2) discover what data sets are available for
solving the users particular science problem - (3) provide a means to access this data or
resource - (4) provide tools to help personnel use the data
that they have found.
3What is a VxO?
- A Virtual Observatory (VO) is a suite of
software applications on a set of computers that
allows users to uniformly find, access, and use
resources (data, software, document, and image
products and services using these) from a
collection of distributed product repositories
and service providers. A VO is a service that
unites services and/or multiple repositories. - An observatory is a location used for observing
terrestrial and/or celestial events. - A virtual observatory is a system that allows an
observer to work as if they were at the
observatory. - The VO does this typically by allowing the
observer to access multiple data files
(observations) from multiple sources of the
object of interest. - The VO allows access to different instruments
to study a given system or phenomena. - VitmO ties together multiple data sets from
different satellites and ground stations to
create the appearance of having many different
types of instruments observing the same phenomena
from different locations.
4Virtual ITM Observatory
- The Virtual ITM Observatory (VITMO) is one of the
recently awarded domain specific NASA virtual
observatories (VxO). - VITMO will focus on data covering the ITM region
as well as providing connections to the energy
drivers for this region (principally solar and
magnetospheric). - VITMO is focused on the interdisciplinary ITM
user rather than the instrument team user.
5ITM is Diverse in Observables
An ITM VO must facilitate correlative study
between multiple parameters from multiple sources
and cross-discipline studies.
6ITM Domain Differences
- Data covering the ITM region has a number of
differences from data in other domains. - The ITM region is observed by ground based remote
sensing instruments, satellite based remote
sensing instruments, and in-situ satellite
instruments. - There are external drivers in solar radiation and
the solar wind and magnetospheric particle
inputs. - A Virtual Observatory that covers the ITM region
needs to deal with the large diversity of data
types in the study of this region. - A heterogeneous data format environment also
exists here. - Solar imagery is typically in FITS files, ground
based data are typically ASCII or NetCDF, in-situ
satellite data are commonly in CDF format, remote
sensing satellite data are typically HDF, NetCDF,
or CDF. - Non-NASA data sources (i.e. NSF, NOAA, DoD) are
important contributors to the ITM domain.
7Discovery of Data
- With the introduction of imaging instruments in
ITM physics the data volume has exploded. There
are now terabytes of data in the ITM domain. - This talk will focus on (2) discover what data
sets are available for solving the users
particular science problem. - VITMO uses an approach where external databases,
calculated events, or other externally generated
event lists can be used to restrict data searches
to precise periods of relevance to the user study.
8The Ability to Find the Appropriate Data Will Be
a Key Requirement of a VITMO
Increasingly satellites in the ITM community will
rely on remote sensing instruments TIMED, DMSP,
NPOESS
9Typical Researcher Workflow
http//swdcwww.kugi.kyoto-u.ac.jp/index.html
- Workflow
- Identify periods of interest (onset of storm,
etc) - Go to various websites to download data from
different instruments - Plot data to identify overlaps in time and space
of data sets - If appropriate data not found repeat loop with
different time period
http//www.srl.caltech.edu/ACE/ASC/
10Download Data from Different Websites
11Check Data from Different Satellites for
Coincidences
April 2 UT
Dec 18 UT
12Metadata Limits the Searches
- Typical metadata does not allow the level of
search that our typical researcher would like to
make. - Typical metadata includes
- descriptive metadata includes program, satellite
and instrument information, as well as data
details like observed phenomena or physical
parameters measured, units of measure, time and
spatial coverage (at a broad level only),
processing level - structural metadata defines the details for data
access and retrieval if selected by the use - Typical metadata does not include
- Time and location information at the pixel level
13VITMO Search Architecture
VITMO
VITMO Metadata Catalog
ACE
SuperDARN
TIMED
CDAWeb
VSTO
14Solar Geophysical Indices Database
- The TIMED program maintains a database of Solar
Geophysical Indices that the ITM community
decided were relevant. - VITMO queries the TIMED Oracle database directly
pulling the SGI parameters of interest. - We then build windows when all conditions are
met.
15Coverlet Windows
Event A 3ltKplt4
Event B Solar Wind Speed gt 400 km/s
Event C Bzlt0
Resultant Timeline
16What will VITMO search capability mean to users?
- By taking on a more global view of data, VITMO
can help the researcher understand the
connectedness between the different data sets. - Example - storm studies - taking the Halloween
2003 superstorm as a case study. - During this event the following things happened
(1) 3 active regions (ARs) produced a total of at
least 124 soft X-ray flares and more than 60
coronal mass ejections (CMEs) between Oct. 18 and
Nov. 5, 2003. (2) 2 CMEs impacted Earth head-on
producing huge geomagnetic storms. - Today without VITMO
- A researcher may start with LASCO images and ACE
solar wind data over the broad time range in
October and November 2003. If the researcher was
interested in auroral impacts from the storm they
may have looked for time periods when Kp was
between 3 and 9 and Bz was negative. - They might have looked for Polar and GUVI imagery
or auroral conductivity maps during those time
periods. - All of this work would have involved finding and
navigating numerous web sites that provide data,
indices, and other information for the specific
time period. - Now with VITMO
- The researcher will be able to select the needed
LASCO images and ACE solar wind data. - They will also be able to select auroral data
during the time periods when Kp is between 3 and
9 and Bz was negative. - The VITMO, knowing that the researcher was
interested in auroral data, would have
automatically presented GUVI and Polar instrument
products as appropriate. - It would then suggest data readers, appropriate
for the data format, and tools that the
researcher could use to work with or analyze that
data.
17Data Search Before VITMO
18Select Coverage
19Select Physical Parameters
20Restrict Coverage
21Select Products for Download
22Coverage Windows
23Files Are Packaged Up For Download
24Applicability to ITM Research
- Example Using TIMED GUVI data the researcher
has identified ring current aurora (dayside
detached arcs, nightside detached aurora, proton
spots, etc). - It is noted that in the cases examined certain
geophysical conditions occur. - Search for all data (from other instruments as
well) under those conditions to identify
occurrence frequency.
25Overcoming the Limits of Our Metadata
GUVI 1356 Å
Plasma bubbles
Limb Scan
74o Inclination
Cross-track scan perpendicular to orbit
Disk Scan
Equatorial arcs
26Calculated Databases
- VITMO will employ special coincidence calculators
that know the viewing geometries of the various
instruments. - The TIMED coincidence calculator is an example of
a tool which when converted into a web service
can be used to augment existing data querying. - The TIMED coincidence calculator has recently
been imbedded into the TIMED query system. - These calculators will operate as web services
inside the VITMO query system (or by outside
query systems). - These calculators generate metadata for the
coincidence of interest which is used by the
catalog system to answer your query. - The metadata generated by this service is
discarded after it is used hence virtual
metadata.
27Not Plotting Tools Imbedded Into Query
28Coincidence Calculator
29VITMO Search Architecture
VITMO
VITMO Metadata Catalog
SuperDARN
TIMED
CDAWeb
VSTO
ACE
30Enhanced Query
- With the inclusion of virtual metadata sources a
user can go to VITMO to ask During the last 6
months where are GUVI EDP products over Millstone
Hill radar when Kp gt 3. - The coincidence calculator will calculate when
the GUVI product overlaps spatially and
temporally with Millstone Hill. - This is combined with when Kp gt 3.
- Query is sent to VSTO or MADRIGAL to find
appropriate radar or other products. - All data products returned for download.
31Enhanced Search Results
- Addition of virtual metadata capabilities allows
pre-selection of data for analysis. - VITMO search will employ calculator services that
allow us to deliver results from searches such as
What GUVI data that contains 23-01 MLT during
active geomagnetic conditions?
32Products of Searches Are Windows
- Products of searches are windows of time.
- Future products of searches may be products of
time and space.
33Find Data During Events
- Capability exists to search for data from a
library of events - Solar flares
- Geomagnetic storms
- User generated conditions
- Model data comparisons
- Identify where GUVI electron density profiles
deviate from International Reference Ionosphere
calculations in latitudes between 30 mlat by
more than a factor of two. - Now find all DMSP SESS ionospheric data at the
same time and location.
34VITMO Search Architecture
VITMO
VITMO Metadata Catalog
SuperDARN
TIMED
CDAWeb
VSTO
ACE
35Conclusion
- Addition of SGI databases, on-the-fly calculated
databases (virtual metadata generators), and
event listings greatly enhance the search
capabilities far beyond the limitations of the
present metadata available to describe products
in our domain. - The VITMO prototype is available at
HTTP//vitmo.jhuapl.edu. - VITMO will be operational at the end of 2007.