The primary purposes of the Halley Watch have been to promote Halley observations, coordinate and standardize the observing where useful, and to archive the results in a database readily accessible to cometary scientists. The intention of IHW is to store the observations themselves, along with any information necessary to allow users to understand and use the data, but to exclude interpretations of these data. Each of the archives produced by the IHW will appear in two versions: a printed archive and a digital archive on CD-ROMs. The archive is expected to have a very long lifetime. The IHW has already produced an archive for P/Crommelin. This consists of one printed volume and two 1600 bpi tapes. The Halley archive will contain at least twenty gigabytes of information

Mcguinness, Brian B.

English

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N89- 13345 i
CURRENT STATUS OF THE INTERNATIONAL
HALLEY WATCH INFRARED NET ARCHIVE
Brian B. McGuinness
Department of Earth and Space Sciences
State University of New York at Stony Brook
Stony Brook, NY 11794-2100
v
The primary purposes of the Halley Watch have been to promote Halley observations,
coordinate and standardize the observing where useful, and to archive the results in a
database readily accessible to cometary scientists. The intention of the IHW is to store the
observations themselves, along with any information necessary to allow users to understand
and use the data, but to exclude interpretations of these data. It is important to note
that submission of observations to the IHW does not preclude the publication of these
observations in journals. In fact, observers are urged to publish their data promptly in the
open literature. Data submitted to the Infrared net of the IHW will not be released until
the IHW archives are released.
Each of the archives produced by the IHW will appear in two versions: a printed
archive and a digital archive on CD-ROMs. The CD-ROMs will contain everything sub-
mitted in digital form to JPL. Due to cost constraints, the printed archives will contain
some, but not all, of the information in the digital archives for each of the observations.
The printed versions will allow astronomers to quickly look up information and will give
them an idea of what type of information is available on what dates. Each entry will con-
tain the ID number of the corresponding file in the digital version, so the printed archives
will be useful as indices to the CD-ROMs. The digital archives will allow the data to be
easily accessed by computers for data reduction and analysis. CD readers for IBM PCs
and other microcomputers are available to read the CD-ROMs. Thus, access to the digital
archives will not be excessively expensive.
The archive is expected to have a very long lifetime. Experience indicates that mag-
netic tapes deteriorate to uselessness after only ten years or so. As CD-ROMs were de-
veloped relatively recently, their useful lifetimes are unknown, but they are expected to
last at least 30 or 40 years. When they start to wear out, they can be copied onto newer
CD-ROMs or other media. The archive is expected to be used at least up through the
next apparition of Halley.
The IHW has already produced an archive for P/Crommelin. This consists of one
printed volume and two 1600 bpi tapes. The CD-ROM version is contained in the Planetary
Data System's (PDS) Interactive Data Interchange (IDI) disk. The Crommelin archive was
created as a test of the Halley Watch. It enabled the IHW to determine what problems
would be likely to appear during data collection for the creation of the other two archives.
The proposed format for the printed versions of the G-Z and Halley archives has changed
considerably based on experience gained from the Crommelin archive. Furthermore, the
indexing scheme used for the G-Z and Halley digital archives will differ substantially from
that used for Crommelin. Nonetheless, the Crommelin archive is a useful source of data,
although its distribution in CD form has been far more limited than is planned for the
Halley and G-Z disks.
The Halley archive will contain at least twenty gigabytes of information - possibly
twice that. Recent estimates are that the printed version will consist of seven 500-page
volumes and the digital version will consist of perhaps twenty CD-ROMs, depending on
the data-compression techniques employed. This is obviously a large collection of cometary
data.
The printed version of the Giacobini-Zinner archive will be published in November
1988, followed by the digital version in mid-1989, The printed Halley archive will be
117
https://ntrs.nasa.gov/search.jsp?R=19890003974 2020-03-20T04:44:52+00:00Z
publishedabout October 1, 1989,and the digital versionin mid-1990.
The IHW issubdividedinto ninenets: Astrometry,InfraredStudies,Large-ScalePhe-
nomena,Near-NucleusStudies,PhotometryandPolarimetry,RadioStudies,Spectroscopy
and Spectrophotometry,Amateur Astronomers,and Meteor Studies. Eachof thesenets
is headedby oneor moreDisciplineSpecialists,who decidewhat typesof information to
includein the archivesandcollectobservationsfrom the observersin their nets. Discipline
Specialistsfor the Infrarednet areR. Knackeand T. Encrenaz.The DisciplineSpecialists
givethe data they collect to their SoftwareSpecialists,who convertit to FITS [1,2]format
and write it ontomagnetic tapes. The tapesare then sent to the Lead Centerat JPL in
Pasadena,California, wherethe final editing and publicationaredone.
TheIHW infraredcenterat StonyBrookhasthe taskof decidingwhat typesof infrared
data to include in the archive,soliciting this information from the observers,determining
theformat for both the printedanddigital versionsof the archive,collectingandorganizing
the data, verifying that the datawerereceivedcorrectly,and convertingthe data to FITS
format for submissionto the Lead Center. From time to time the DisciplineSpecialists
and the SoftwareSpecialistfor the IR net meetwith their counterparts from the other
nets and personnelfrom the LeadCenterto discussthe formats for the archivesin order
to achieveconsistencyacrossthe nets. They alsoworkon designingan indexingsystemto
allow data on the CD-ROMsto bequickly and easily located.
Information submitted to the IR net isstoredon a hard diskon an IBM PC/XT with
a commercialdatabaseprogram. Whencomplete,a printed copy is sent to the observer
to be checkedfor errorsand returned with corrections.It is then exportedto ASCII text
files and convertedinto FITS format. Oncethe FITS fileshavebeencheckedfor errors,
they areuploadedat 9600baud overa direct line to a DEC MicroVAX. From there they
arewritten to tape and then mailedto the LeadCenter.
Figures1 and 2showthe generalstatusof the IR net in April and August 1987.The
proportion of the total data that hasbeenreceivedso far hasincreased,for two reasons.
First, the IR net has receiveda largeamount of information sinceApril. Secondly,the
estimatedtotal amountof informationexpectedhasdecreasedasobservershavereported
that certain observationswerenot madedue to badweatheror other problems.As infor-
mation hasbeenprocessedand submitted to JPL, more information has arrived, so the
total amountof information in preparationhasstayedfairly constant.
Figures3 and4 givea breakdownof the informationby type. Infraredobservationsof
Halley aredominatedby photometry. The IR net hasbeenprocessingHalleyphotometry
and polarimetry data and hasbegunwork on spectroscopy.There arestill a few details
about the digital format for imagesthat needto be worked out beforethe imagescan
be processedand submitted. Due to this and to the small amount of Giacobini-Zinner
photometry and spectroscopydata receivedsofar the G-Z data havenot yet beenfully
processed.Processingof the G°Z photometryand spectroscopydatashouldbecompleted
by the end of January 1988.
Figures 5 and 6 show the number of nights of observations made each month during
the recent apparitions of Giacobini-Zinner and Halley.
The IHW infrared net needs the continued support of the observers. For the G-Z and
Halley archives to be as useful as possible, observers must submit all available data so that
the archives can be complete collections of the observations. It is also necessary for the IR
center to be made aware of observations that were planned but not made in order for its
calendar of observations to be updated. The Lead Center must operate with a continuous
inflow of observational data. Each individual who contributes data will be given a free
copy of the archives, both in the printed and digital forms.
The archive publication dates mentioned above set deadlines for data submission. The
IR net needs time to organize and reformat the data. Extra time is required for dealing
with unexpected problems such as hardware breakdown or difficulty in reading tapes. In
118
addition, the Lead Center needs time to organize the data received from the nine IHW
nets. The Giacobini-Zinner data should have been delivered _bYDecember, 1987. Please
contact us if you have data but could not meet the deadline. Halley observations should
be submitted by June 1988.
Data may be submitted to the IHW infrared net in the form of tables, notes, computer
printouts, or magnetic tapes mailed to either Dr. Roger Knacke or Brian McGuinness at
the following address:
Department of Earth and Space Sciences
State University of New York at Stony Brook
Stony Brook, NY 11794
or to:
Dr. Therese Encrenaz
Observatoire de Paris
Section d'Astrophysique
92190 Meudon, France
We prefer that magnetic tapes be written in unlabelled form. Files on the tape should
be written as ASCII text files or as FITS files. The tape density should be 1600 or
6250 bpi. When sending tapes, please indicate what format the tape is written in (plain
unlabelled form, ANSI-D, or whatever) and what type of computer it was written on.
Some computers, such as the Prime, have idiosyncrasies that affect tapes written by them.
It would also be appreciated if the tape was accompanied by a list of what files it contains.
This aids in the detection of errors during the process of reading the tape.
An alternative is to send the observations in the form of electronic mail on BITNET
to BMCGUINESS_@SBCCMAIL. This will cause them to be sent to the Stony Brook
Computing Center's VAX 8600 computer system. From there they can be downloaded to
the IBM PC/XT for processing.
REFERENCES
[1] Griesen and Harten, 1981, Astron. Astrophys. Suppl. Ser., ,14, 371-374.
[2] Wells, Greisen, and Harten, 1981, Astron. Astrophys. Suppl. Ser., 44, 363-370.
119
II_lW Infrared Network
Data Reporting as of April 1987
Reported
reparation
62
All Data Reported Data
Figure 1.
IHW Infrared Network
Data Reporting as of August 1987
Unr'o°r"  12 3
All Data
Submitted
Repo r te d
22g
Figure 2.
120
Reported
In PreParation
64
Data
ORIGINAE PACE Ig
OE POOR QUALITY
Infrared Data Status (G-Z)
FHe_ Figure 3.
10
5
0
Photometry Int. Rea, SI3eo High Ree, Sloea Polarlmetry Imaging
Expected I_ Reported _ Sulomitted
Infrared Data Status (Halley)
F,=, Figure 4.
360,
300
250
200
150
100
50
0
iii iiiii!!i!iii !iiiiii.i.+iiiii
Photometry Int. Rea. $1oac High Ree. $1oec Polarlmetry Imaging
Expected _] Reported _ Submitted
121
Giacobini-Zinner Infrared Science
Monthly Log of Observations
Numiaer of Nights
8
0
Jun Jul Aug Sep
l _e85 I
Photometry
Imaging
lVlonths
Rq:]:! Int. Rea. SDec F-_ High Rea. ,Spa F:::::I Polarlmetry
Figure 5.
Halley Infrared Science
Monthly Log of Observations
Number of Nights
60
60 .................................................
40 ........................................
30
2O
10
0
.........................................f t fli: ......... i'-i";-i'": .............. LJLt r..... "
SONDJFMAMJ JASONDJ FMAMj JASONDJFM
I _e84 I 798e I 198e 11987 I
Photometry
E_ Imaging
Month
E]_ Int. Rea. 8pec F7"7] High Ree. SI0e E_ Polatlmetry
Figure 6.
122


Current status of the international Halley Watch infrared net archive

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