# Presentation: 250903

## Long-Term Preservation ofAstronomical Research Results

*Robert Hanisch*
- US National Virtual Observatory
- Space Telescope Science Institute
- Baltimore, MD
*  *

## Electronic information in astronomy

- Astronomy was one of the first scientific disciplines to pioneer e-publishing (ApJLett 1995, ApJ and AJ 1996)
- Astronomy has comprehensive e-abstract and bibliographic services
- Astrophysics Data System, SIMBAD, NED
- Astronomy makes extensive use e-preprints on arXiv.org
- Astronomy data is archived and is generally publicly accessible
- NASA mission archives
- ground-based observatories (U.S., Europe, Australia, etc.)
- data centers (catalogs, tables, value-added services)

## Electronic information in astronomy

- libraries

- E-journals link to underlying data, and data archives link to e-journals, through a system of persistent, unique identifiers
- Astronomers interact with a set of connected electronic resources

- journals,
- e-prints

- archives and
- data centers

- bibliographic
- services

## The Virtual Observatory

- The *Virtual Observatory* is a framework for providing access to distributed data, distributed services.  The VO is about *data discovery, access, and integration*, and combining data with computational services.
- Motivation:
- The data deluge.  Needs tools to locate and sift through immense collections and to correlate data from many resources.  ~500 TB of data currently available.
- Scientific discovery opportunities exist at the intersections of diverse data sets.
- Astronomy, of course!  Space science, solar physics, aeronomy, seismology, oceanography, hydrology, biology, genomics, medicine.  [...]ology and [...]onomy.
- Keywords:  *Metadata, interoperability*

## Data/Information in the VO

- Basic data
- digital images, spectra, time series,                           catalogs, tables
- Simulations
- models (results, computer codes,                       computational services)
- virtual observations
- Analysis and interpretation
- journals, e-preprints
- reprocessed and enhanced data
- Name-resolution services
- “Andromeda Galaxy”, “Messier 31”, “M31”, “NGC 224”, “UGC 454”, etc. ==> ra 00h 42m 44s, dec +41o 16’ 08”
- Geographic equivalent of “Glenn Dale, MD”, “20769”, “Prince George’s County” ==> 76o 48’ 19 W, 38o 58’ 36” N

*not discoverable through text-based search engines*

## The Virtual Observatory in Astronomy

- The Virtual Observatory enables new science by greatly enhancing access to data and computing resources.  The VO makes it easy to locate, retrieve, and analyze data from archives and catalogs worldwide.
- The VO is NOT a huge centralized data repository.
- The VO provides standard protocols for obtaining data from *distributed collections.*
- The VO is *national* (US NVO) and *international *(IVOA)*.*
- US National Virtual Observatory is partnership of (real) observatories, universities, IT/CS groups.  NSF-funded.
- International VO Alliance is self-organized collaboratory    and standards body (W3C-like).

## Without VO

- astronomer

- archive 1

- survey 2

- survey 1

- archive 2

- service 1

- archive 3

- service 2

- survey 3

- service 3

*n* services, *n *interfaces

## With VO

- astronomer

- archive 1

- survey 2

- survey 1

- archive 2

- service 1

- archive 3

- service 2

- survey 3

- service 3

*n* services, “1” interface

- VO

## Data integration

- optical (HST)

*Cas A supernova remnant*

## Data integration

- radio (VLA)

## Data integration

- x-ray (Chandra)

## Data integration

- x-ray (Chandra)

## Data integration

## The Key to the VO: Interoperability

- Metadata standards
- Data discovery
- Data requests
- Data delivery
- Database queries, responses
- Distributed applications; web services
- Distributed storage; replication
- Authentication and authorization

## The data preservation problem

- Research communities publish peer-reviewed journal papers that describe highly processed data.
- Long-term preservation and curation systems for digital journal content are not currently in place; *only the graphical representations of data are being saved*.
- The research cannot be verified and the results cannot be easily compared to other data in order to broaden impact.
- Public funds invested in scientific research do not have maximum return on investment.  Essential legacy datasets are being lost.

## Astronomy Digital Image Library

## ADIL

- query

## ADIL is great, but...
Data capture and curation is separate from manuscript processing
Data access is not integrated into the journals
Data management is centralized

- ADIL
- query

- ADIL is great, but...
- Data capture and curation is separate from manuscript processing
- Data access is not integrated into the journals
- Data management is centralized

## Spectral data in NED

## Spectral data in NED

## Spectral data in NED

## Spectral data in NED

- NED spectra are great, but...
- Data capture and curation is separate from manuscript processing
- Data access is not integrated into the journals
- Data management is centralized

## Storyboard

## Storyboard

- Hubble Space Telescope image.
- Most distant cluster of galaxies known.
- What more can I find out?

## Storyboard

- Where is this?
- What is the image scale?
- Where is north?
- How bright is the star?
- How bright is the galaxy?
- What else is known about this region?
- Can I trust the data analysis in this paper?

## Storyboard

- Save file
- Copy to my VOSpace

- Display and compare

## Slide 27

## Slide 28

## Journal...      			  Archive...

- Journal...      			  Archive...

## Slide 30

## Slide 31

## Slide 32

## Slide 33

## Is there any X-ray emission from this cluster of galaxies?

## Approach

- Integrate digital data management into the publication process (data capture, review, metadata tagging and validation, storage).
- Exploit emerging information technology standards for managing distributed data collections, including digital journals.
- Provide multiple access methods to digital data to maximize visibility and re-use.
- Exploit information management and curation experience in the university libraries and build on long-term institutional commitments to preservation.

## Components

- Data Storage Appliance
-  Metadata database
-  Digital data objects
-  Ancillary information

- Data Storage Appliance
-  Metadata database
-  Digital data objects
-  Ancillary information

- Data Storage Appliance
-  Metadata database
-  Digital data objects
-  Ancillary information

- replication services

- VOSpace

- Publication &
- Editorial Process
-  Data capture
-  Metadata capture & validation
-  Links
-  Identifiers

- Data Access
-  VO portals
-  Journal portals
-  Other after-market distributors
-  Registry
-  Logging

- Library
-  Curation
-  Preservation

## Data preservation tasks & partners

- Tasks (partners)
- Metadata definition (VO, library)
- Content management tool evaluation/selection (Fedora) (VO, library)
- Physical storage and replication (VO, library, publisher)
- Publication process revisions and testing (publisher, editorial staff)
- Policy development (editorial staff, professional society)
- Business model development (publisher, professional society)

## The curation challenge

- Digital data is useless without accurate metadata
- Data collections cannot be located/queried/ mined without accurate metadata
- Metadata curation can be automated, but not completely
- Curation is an ongoing and significant cost for digital data management
- Virtual Observatory registry
- Data archives

## Digital data discovery and access is essential for the research community

- Data re-use, with provenance
- Optimization of public investment in science
- Increasing the discovery space
- Creation of a research legacy
- Integrity in scientific publication
- Success requires cooperation among providers (individual and institutional), publishers, curators,  and preservationists