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Astronomical Data Analysis Software and Systems VII
ASP Conference Series, Vol. 145, 1998
R. Albrecht, R. N. Hook and H. A. Bushouse, e
Ц Copyright 1998 Astronomical Society of the Pacific. All rights reserved.
ds.
Archiving Activities at the Astronomical Observatory of
Asiago
A. Baru#olo and R. Falomo
Astronomical Observatory of Padova, Italy
Abstract. Since July 1993 all observations collected by the 1.82m tele­
scope at Cima Ekar (Asiago) are systematically archived on DAT car­
tridges and a listing of collected data, including all parameters of the
observations, is maintained in a relational DBMS. In order to promote
the scientific reuse of observations stored in this archive, we have devel­
oped a WWW interface based on the WDB software, that enable users
to perform complex searches in the observation log. In this paper we
give an overview of the archive, briefly describe the WWW--based search
interface as well as planned future enhancements to the archiving system.
1. Introduction
In the past few years astronomers which observed with the Copernico 1.82m
telescope have asked for an archiving facility that could serve as a repository
of all observational data and provide astronomers with a backup copy of their
observations in case of data loss.
Following this request, since July 1993 an archiving facility has been set up
at the Astronomical Observatory of Asiago (Mt. Ekar) where all observations are
routinely stored on DAT cartridges and catalogued using a relational DBMS. In
a first phase, the archive facility did not foresee network access: archive searches
could be performed only at the Mt. Ekar Observatory archive system, or at a
twin system located at the Astronomical Observatory of Padova.
In order to give access to the Copernico Archive to the widest possible
community of users, a WWW--based search facility was developed and installed
at the Astronomical Observatory of Padova, which is better connected to the
Internet.
In this report we give an overview of the archiving system and describe the
main features of the WWW--based search interface.
2. The Archiving System
The Copernico Telescope Archiving System is made up of a master archive,
where the observation list is generated and maintained, and a public archive,
where a copy of the observation list is accessible through a WWW--based inter­
face.
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Archiving at the Astronomical Observatory of Asiago 401
The master archive software consists of a collection of programs that run
in the Windows environment and that use the FoxPro relational database man­
agement system (RDBMS) for data handling. It allows for:
. daily ingestion of the list of new observations;
. correction/insertion of incorrect/missing data;
. local archive searching.
The observation list maintained in the master archive is named the master
catalogue: corrections and updates are made to this list only, they eventually
propagate to the public archive during the periodic transfer of data from the
master to the public archive.
The public archive software consists of a collection of programs that run on
a Linux system and that use the MiniSQL RDBMS (Hughes Technologies 1997).
It is responsible for:
. periodic synchronization of the public archive's content with the master
archive;
. handling of queries from archive users.
3. Overview of the Archiving Process
During the observations all images and spectra taken by the astronomer are
stored on disk in FITS files by the data acquisition system (Baru#olo & D'Ales­
sandro 1993). At the end of each observing night these files are transferred on
DAT cartridges: during this step a listing of observations is generated and this
list is ingested into the archive. For each data file parameters that characterize
the observation are extracted or derived from the FITS header and the data are
displayed and checked for consistency; three other parameters which give the
location of the data on the archive medium are then added to those describing
the observation.
Periodically the most recent part of the observation catalogue is dumped to
ASCII files and transferred to the public archive. In the public archive machine
a procedure automatically starts at fixed intervals, checks for new data coming
from the master archive and loads them into a miniSQL database. During
this pass some additional checks are performed on the data and a report is
generated signaling errors and/or missing data so that the master catalogue can
be corrected further.
4. Archive Content
At the time of writing, the Asiago archive contains more than 16000 frames. This
figure includes all science exposures (images and spectra) and all calibration data
(bias, dark, flat field and comparison spectra). Table 1 gives a summary of all
archived data by image type and by instrument.

402 Baru#olo and Falomo
Table 1. Summary of the archive content by image type and by in­
strument
Image type Nr. of Frames
tvcamera 11
test 143
bias 1069
calib 3339
dark 153
flat 2248
focus 244
object 8821
Instrument Nr. Of Frames
Boller & Chivens 7105
Echelle 5498
Imaging camera 3425
5. WWW Access to the Archive
WWW access to the archive is available from the Asiago Observatory Home
page 1 and is realized using the WDB software version 1.3a (Rasmussen 1995),
modified to work with miniSQL and to allow ordering of results on a user­
selected field. When the user accesses the archive by opening its URL in a Web
browser, a query form is generated on--the--fly by WDB on the basis of a form
definition file (FDF). Searches can be constrained by filling in the form and then
clicking on the search button; archive last modification time can be retrieved
by following an hyperlink located towards the top of the query form.
The query form consists of action buttons, which initiate an action when
clicked, query fields, which are used to constrain searches, additional parameters,
which can be added to the query output, and output controls, which control how
query output is formatted and how many data rows are retrieved by a query.
These items have been discussed in detail in another paper (Baru#olo, Falomo,
& Contri 1997).
6. Requesting Archived Data
At present there is no facility for automatically requesting data that have been
selected using the archive query form. A user willing to retrieve data from
the archive must send the list of requested observations (that must include the
keyword ``CODICE'') to the archive maintainer who will forward it to the technical
sta# at the Asiago Observatory. Observations will then be retrieved from the
archive media and delivered to the requester on DAT cartridges or stored on
disk for ftp transfer. Further information on how to request archived data and
contact points for the archive maintainer can be found on the archive WWW
page.
The actual policy of the Observatory on data distribution is that the ob­
servations become public domain two years after the observation date.
1 http://www.pd.astro.it/asiago/asiago.html

Archiving at the Astronomical Observatory of Asiago 403
7. Conclusions and Future Work
In 1993 we started to systematically store all observations collected at the 182
cm. telescope in FITS format and to produce listings containing the parameters
that characterize them. At that time the development of the Web was still in
its infancy and network access to the archive was not foreseen, since this would
have implied the development of a custom client/server user interface. However,
having maintained the observation list in a relational DBMS has allowed us to
upgrade the archive system with Web access with relatively little e#ort.
The WWW interface to the archive has been available for more than one
year now, no major problems were reported during this initial operational period.
Future work on the public archive is planned to provide preview images,
storage of data on optical disks (recordable CD--ROMs) and to automate archive
data requests.
Finally, it is to be noted that provision has been made in the public archive
software for inclusion of observations coming from the other two telescopes work­
ing at the Asiago sites: the 67/92 cm. Schmidt and the 122 cm. telescope. For
the first of these, which still operates using photographic plates, a preliminary
database (only working on a PC) is available, it contains data collected since
1965. The 122 cm. telescope has been recently equipped with a CCD detector
and it is planned to only archive these recent data.
References
Baru#olo, A., & D'Alessandro, M. 1993, Padova and Asiago Observatories Tech.
Rep. No. 3
Rasmussen, B. F. 1995, in ASP Conf. Ser., Vol. 77, Astronomical Data Analysis
Software and Systems IV, ed. R. A. Shaw, H. E. Payne & J. J. E. Hayes
(San Francisco: ASP), 72
Hughes Technologies, 1997, ``Mini SQL 2.0. User Guide.''
Baru#olo, A., Falomo, R., & Contri, L. 1997, Padova and Asiago Observatories
Tech. Rep. No. 12