This section is dedicated to
Astronomical Archives used for NEO precovery work and consists in a network of
links about the activities and the archives used by a few dedicated teams.
This page is organized in a very simple way. After a brief hystorical review of what has been done
in the past and why archives are so important for NEO work,
we provide four general listings that include:
i) general archival resources;
ii) a review of the teams/individuals involved in precovery work;
iii) a collection of archives currently used in NEO precovery work,
both photographic and CCD.
Hystorical Review and the Importance of Archives
Precovery searching for minor bodies (comets and asteroids) is not a new activity since it has led
to scientifically valuable results in the recent past. For example, the identification of the
Amor-type object (4015) = 1979 VA with Periodic Comet Wilson Harrington (1949 III) on two plates
from the First Palomar Sky Survey (
Bowell 1992), showed
clear evidence that the distinction between asteroid
and comets is not very straightforward. The well-known comet Hale-Bopp had its orbital solution
significantly improved thanks to precovery data obtained during the early stages of the
follow-up process (
The interest for astronomical archives has grown significantly in the NEO community in the past
few years. This is because studies and discussions among scientists have concentrated more and more
on the hazard aspect of these bodies. It is becoming clearer and clearer that hazard mitigation
requires much more than just discovery: there is a need to obtain very good orbits of NEOs in the
shortest possible time. The inspection of astronomical archives is one of the most interesting
and rapid methods to meet this goal. It was aptly demonstrated recently when two km-sized
1997 XF11 and
were found to have very small collisions probabilities with
the Earth. The collision solutions could be excluded with data from photographic archives.
After the pioneer efforts of the Anglo-Australian Near-Earth Asteroid Survey (AANEAS) in
1990-1996, newly discovered NEOs are now routinely searched for on some archival resources (mostly
photographic) by a variety of dedicated programs. These initiatives have benefited from one
obvious factor in common: access to some local archival resouces. Part of their success
is that they could conduct this activity without travelling around the world, because the working
By using these available options the teams involved in archival searches have managed to secure
the orbit of almost 200 of the more than 500 multiple-opposition NEAs currently known
(as of October 18, 2001). About 80 % of these identifications was made in the past two years alone,
mostly by DANEOPS and ANEOPP: 90 % of these were made on photographic archives and 10 % on CCD resources.
It is clear that CCD can even play a more important role in the coming years if data is appropriately
preserved and made available to the community.
- Owns the plate collection.
- Is based where the plates are stored.
- Remotely retrieves archival material in a digital form on the internet.
Teams and individuals currently involved in this activity
Here we provide a list of people and teams involved in NEO precovery work. Some
of them carry out this activity systematically, maintaing a costant level
of attention on all the newly discovered NEOs. Part of their activity is also
devoted to main-belt objects (MBOs), as well as other unusual objects.
Other individuals, who may have access to additional archives have been willing
to look for specific objects, but they do not currently carry out a systematic
effort for all the known NEOs. Further occasional collaborators come from
astronomers not too expert in the field
they may need some assistance during their initial experiences.
- Systematic Activity
- Non Systematic Activity
Each team/individual is flagged with a three letter designation (in parenthesis)
that will be used later in the list of archives currently available for work.
While the DANEOPS team is rapidly incresing the number of archival collections
available for their work, at the SCN we have been trying to expand the number
of people who are willing to collaborate on an occasional basis, so that a
wider range of archives could be accessed. In addition to targeted efforts,
a collaboration can result in planning work visit where these archives are
stored for a more systematic work.
General Archival Resources
Wide-Field Plate Database (WFPDB) - CDS contains the descriptive information for
the astronomical wide-field (~>1 deg.) photographic observations stored in numerous archives
all over the world. The Catalogue of Wide-Field Plate Archives
(WFPA) is prepared in the
Institute of Astronomy at the Bulgarian Academy of Sciences within the activities of the
IAU Commission 9 Working Group on Wide-Field Imaging, founded in 1991.
The UDAPAC project: Uccle Direct
Astronomical Plate Archive Centre. It was born in March 2000 with the goal to digitize
about half million direct photographic plates in a time frame of 5 years.
Archives used for NEO precovery work
There are several hundred of photographic archival collections, consisting of
more than two million of plates all over the world. Only a minor fraction
of these are really suitable for NEO work and a smaller percentage of this
is available in some way to the community for investigation and study. In the
following scheme we have divided the archives available (both photographic
and CCD) into three catgories:
- (A) - archives directly accessible at any time (at least for one team)
Precovery plans for NEOs with large uncertainties can be set-up ahead of time and
pursued until success if there are indeed images that contain the desired object.
- (B) - archives not directly accessible at any time, but data can be
retrieved through various forms of collaborations. Activity generally limited to
objects with small uncertainty or more improtant for the community.
- (C) - archives not directly accessible at any time and data may not be
retrieved at all, either because of lack of personell or impossibility to find a
Sometime all is available is a catalogue on file or simply on paper. A dedicated
project or a funding program may be needed to extract data from these resources.
For each archive we put its category of accessibility and the designation of the
teams that have been using it. The category may vary from team to team since it
might be better accessible for some people than for other.
The Digital Sky Survey
In order to fully exploit their scientific potential, astronomers realized that photographs must be
converted into a digital format, suitable for computer analysis. This led to the Digital Sky survey
or DSS, a project carried out at the Space Telescope Science Institute (STScI).
The role of the Digital Sky Survey
The Digital Sky Survey is like a virtual observatory. It is the result of a large project,
consisting in the digitization of a set of high-quality plates.The project goal was to map
the entire sky in different colours, typically blue, red and near-infrared. Three telescopes
have been employed in this task: the 1.2-m Oschin Schmidt telescope, the 1.2-m UK Schmidt
telescope in Australia and the 1.1-m ESO Schmidt telescope in Chile.
The role of DSS has gone well beyond the work on NEOs. This great resource has been used to
locate and measure thousands of main-belt objects. This served both the purposes of confirming
many uncertain identifications and of speeding the process of numbering these bodies by the
Minor Planet Center.
POSS-I - First Palomar Sky Survey (1949-1958) - (part of DSS I) :
(A) - DAN - ANP - ALW - RHP
POSS-II - Second Palomar Sky Survey (1985-1999) - (part of DSS II) :
(A) - DAN - ANP - ALW - RHP
POST - Palomar Oschin Schmidt Telescope (1958-1985) :
(B) - PCS : (C) - ANP
- UK Schmidt Telescope Unit archive (1973-2001) - (part of DSS I and II)
Survey plates: (A) - ANP - DAN - RHM - ALW - RHP
Non survey plates: (B) - ANP - RHM - DJA
- European Southern Observatory Schmidt Telescope (1974-1997):
(A-B) - DAN : (B-C) ANP
- European Southern Observatory - WFI, ASTROVIRTEL project. -- ESO-ST :
(A) - DAN
- The Palomar Planet-Crossing Asteroid Survey (1973-1995):
(A) - PCS
- The Palomar Asteroid and Asteroid Survey (1983-1995):
(A) - LOW : (B) ANP - DAN
Indiana Goethe Link
- Indiana Goethe Link plates: (A) - LOW
- Pluto Camera - Lowell Observatory: (A) - LOW
- Lick Observatory Double Astrograph (1941-1988) :
(B) - AKL : (C) ANP
- Kiso Schmidt telescope archive : (B) - DJA
- Tautenberg Schmidt telescope archive : (B) - DAN
- Sonneberg Schmidt telescope archive: (B) - DAN
Bigelow Sky Survey
- Bigelow Schmidt telescope archive : (B) - DAN
Uppsala Sky Survey
- Uppsala Schmidt telescope archive : (B) - DAN
Kvistaberg Sky Survey
- Kvistaberg Schmidt telescope archive : (B) - DAN
Although NEO dedicated programs have been sweeping huge region of the celestial sky by means
of powerful CCD cameras at various limiting magnitudes in these last few years, the number
of available CCD archival resources is still very limited.
Further Useful Links
- Additional archival resources
- ISTeC - International Small telescope Cooperative (to be evaluated)
- Orbital databases
The following papers have discussed precovery work on minor planets, with special
emphasis on NEOs:
- Boattini A., D'Abramo G., Forti G., Gal R., 2001, Astronomy & Astrophysics, 375, pp. 293-307
- McNaught R. H., Steel D. I., Russell K. S., Williams G. V., 1995, IAU Colloquium 148:
The Future Utilization of Schmidt Telescopes , pp. 170-173
- Steel D. I., McNaught R. H., Garradd G. J., Asher D. J., Russell K.S., 1997,
Australian Journal of Astronomy, 7, pp. 67-77
We want to thank A. Doppler, A. Gnadig, R. Stoss, A. Lowe, R. McNaught, D. Asher and B. Skiff for providing comments
and useful information about their precovery activities. The information in this page is still incomplete and might
be affected by several errors. We apologize for that and hope to have your useful comments. Some of the links from this
page are not active yet.
This document was updated on February 19, 2002, by
Andrea Boattini and