Archive Mirror of PPAS8 (Dorreman and Jonckheere) courtesy of Mike McCants
Photometric Periods of Artificial Satellites
This database of Photometric Periods of Artificial Satellites (PPAS)
has been collected by the Belgian Working Group of Satellites (BWGS).
It can be used for research on flash periods of artificial satellites.
So far research on this subject has been hampered by the lack of obser-
vational data. We hope this database can leviate that problem.
The idea to create this database came from Christian Steyaert who dis-
covered the old archive of Jean Meeus (with observations from 1962 until
1978) in 1988. While working on the informatisation of the (new) obser-
vations of the BWGS (which restarted its activities in 1987), the idea
grew to collect all old observations as well. Apart from Jean Meeus'
archive another major source was found in Bertus Kroon's archive. The
observations of the Dutch group that formed around him limited the gap
between Jean Meeus' archive (until 1978) and the current activities of
the BWGS (from 1987 onwards new observations guarantee a follow-up).
PPAS 1 was published in October 1990.
PPAS 2 appeared at the end of 1991. Added were new observations ob-
tained between August 1990 and September 91, and some older observations
(obtained from the archives of our active observers).
PPAS 3 appeared at the end of 1992. The archive of Pierre Neirinck and
Daniel Karcher was added, as were all new observations between September
91 and August 92.
PPAS 4 was published early 1994. New observations between August 1992 and
November 1993 were included. Some small errors were also corrected.
PPAS 5 appeared in January 1995. Part of the archive of the late
Horst Koehnke was added, as were all observations obtained between
December 1993 and December 1994.
PPAS 6 was published in April 1996. It contains more of the archive of
Horst Koehnke, as well as new observations obtained between December 1994
and March 1996. The remarks-file PPAS6.REM was cleaned up and the indexing
of the remarks was improved.
PPAS 7 appeared in May 1997. It contains another part of the archive
of Horst Koehnke, as well as new observations obtained between April 1996
and May 1997. Thanks to the effort of mainly Leo Barhorst a number of
faulty entries in our archive were corrected.
PPAS 8 appeared in January 1999. It contained a number of observations
of Mike McCants' archive, as well as new observations obtained between
May 1997 and December 1998.
Our thanks go to the following people:
- Bart De Pontieu, Bram Dorreman, Kurt Jonckheere, Kurt Osaer, Christian
Steyaert and Patrick Wils who entered all PPAS 1 observations.
- Jean Meeus, Bertus Kroon, Pierre Neirinck and Horst Koehnke for their
- Dirk Carlens, Tristan Cools, Bart De Pontieu, Johannes Fritzer, Kurt
Jonckheere and Jan Vansteelandt for entering the archives of Pierre
Neirinck and Horst Koehnke.
- Kurt Jonckheere for collecting our monthly observations until July 1992.
- Bart De Pontieu for collecting our monthly observations between July 1992
and May 1993.
- Tristan Cools for collecting our monthly observations from May 1993 until
- Kurt Jonckheere and Leo Barhorst for collecting our monthly observations
from April 1996 until August 1996.
- Kurt Jonckheere for collecting our monthly observations from August 1996 until
- all observers for sending in their monthly observations since 1991.
Further acknowledgement goes to the following persons :
PPAS 1 : Bram Dorreman for first editing, uniformisation and synchronisation
between the different sources of PPAS 1.
PPAS 2, 3, 4 : Bart De Pontieu and Kurt Jonckheere for uniformisation and
final editing of these PPAS versions.
PPAS 5 : Tristan Cools for uniformisation and final editing of PPAS 5.
PPAS 6 : Tristan Cools for uniformisation and final editing of PPAS 6.
PPAS 7 : Kurt Jonckheere for uniformisation and final editing of PPAS 7.
PPAS 8 : Kurt Jonckheere for uniformisation and final editing of PPAS 8.
Finally we would like to thank all observers, who despite such hazards as
cold, frustration, fights with the family and other harsh circumstances
persevered and produced such a vast amount of scientific data.
4. Technical details
The PPAS consists of 41 Text or ASCII-files (one for each launch year) which
contain the observations of the satellites launched in that year. All PPAS-
files have the extension '.OBS'. E.g. The file 'PPAS91.OBS' contains all
observations of satellites which were launched in 1991.
It should be noted that the names of all satellites launched before 1963 have
been COSPAR-ized. Official notation uses Greek letters for them. We have chosen
to translate all Greek names to the current COSPAR system (to avoid trouble
with the Greek characters). e.g. 61- alpha kappa 4 becomes 61- 34 D.
USSPACECOM have also adopted this system in 1993.
The file 'PPAS8.REM' contains remarks that were too long to be fitted into the
80 column PPAS-format (see below). The remarks are numbered per satellite.
The numbers in the remarks column of the PPAS-format (e.g. '1)') refer to
the PPAS7.REM file.
5. Special format
Every line (each line is ended by an 'end-of-line' character) contains one
observation. In order to make processing easy, we have used a standard format.
In this format each line is divided in columns and every column always con-
tains the same data. Normally each line contains 80 columns (or characters),
but in order to save space on the disk, every line is ended if the remaining
characters are blank.
This is the format which has been used:
01-08 Cospar-identification of the satellite in the format
yy-nnncc. yy is the year of launch, nnn is the number
of the launch (only contains significant numbers and
is right justified), cc is the piece of the launch (contains
non-numeric characters). e.g. '86- 39 B' was launched in
1986 as the 39 th launch and it was a rocket (B). Normally
an 'A' represents a payload, while everything starting with
'C','D',... is usually debris. An important exception are the
Russian C-1 rockets who transport 8 payloads in one into space.
They always have 'J' as extension.
10-17 Date of observation in the format yy-mm-dd. Here all figures
are given (even non-significant numbers). e.g. '76-03-01' is
March 1 in 1976.
19-28 Time of the observation in the format hh:mm:ss.t . All times
are given in Universal Time (UT). Hours (hh) are measured from 0
to 23 h. Minutes from 0 to 59 minutes, while seconds can be
given up to one tenth of a second. Depending on the accuracy
with which the time was measured, the time can be incomplete.
A lot of observations merely contain the hour. These are mostly
observations of the Meeus archive. Attention should be paid to
observations of which the time is given in this format :
hh:mm.t. This gives hours, minutes and tenths of a minute. Some
observers use it to show their accuracy is lower than 1 second.
This field is blank if no time has been given by the observer.
30-32 An abbreviation of the name of the observer. A list of all abbre-
viations and the observing place of each observer is given below.
The abbreviation used, may differ from the initials to avoid
34-38 Total time in seconds and tenths of a second which passed during
the measurement of the flash period, in the format sss.t . Only
recent measurements contain this information. It can be used to
estimate the effect of a wrong count of periods and to check the
given period (see below). It is blank if not applicable.
40-42 Accuracy in seconds and tenths of a second on the total time if
the total time is given. If the total time field is blank, the
accuracy relates to the period. Some inputs contain '.nn'. This
means the accuracy (probably on the period) is 0.nn seconds.
44-46 The number of periods counted. The total time divided by the
number of periods gives the flash period.
48-53 Flash period in seconds and tenths, hundredths (or even thou-
sandths) of a second in the format ss.tht . The 'point' is
always found at position 50 unless the period is larger than
99.999 seconds. The number of figures given is related to the
estimated accuracy. Usually larger periods have smaller accu-
racy (i.e. they are less accurate!). This field is blank if no
period has been measured or if (more likely) the object did
not show any variation in brightness. In this last case, the
object is 'STEADY'.
55-80 Remarks on the flash-pattern or on other aspects of the passage.
A list of abbreviations which are commonly used is given below.
Normally all remarks are in lowercase, except for 'S' (steady,
which always comes on position 55 if applicable) and some other.
All remarks on one observation are divided by commas. Some
remarks contain numbers in the format 'n)', e.g. '1)'. This is a
reference to the PPAS.REM-file, which has also been put on the
This file contains remarks which were too long to be put in
the usual place. Using the name of the satellite and the number
of the reference it is possible to link both files in mind.
6. Abbreviations in the PPAS-remarks.
The various remarks are separated by a comma and a space. E.g. S, mag +4. The
format for describing the satellites' magnitude is: mag maximum_magnitude->
The '+' is omitted for the minimum_magnitude. E.g. mag +4->8 .
When the minimum is invisible, this is indicated with 'inv', e.g.
mag +5->inv. Some observers only mention the maximum_magnitude,
e.g. mag +5.
The following abbreviations are used in the PPAS-remarks-column.
? the photometric period is uncertain, or the remark which
accompanies this question mark is uncertain.
a the photometric period is an approximation.
b the observation has been made with binoculars. This applies
to most measurements, but is sometimes mentioned explicitly.
dec decreasing in brightness. (sometimes mentioned with sm)
df two flashes in one period.
dif different (maxima)
dm double maxima: two close maxima in one period.
dp double period: the period measured, has been taken between
three (instead of two) similar points in the light curve.
dtm the period was difficult to measure.
fm flat maxima: the brightness remained fairly steady during a
relatively long time. Because of this the exact moment of
maximum is difficult to define.
hp half period: the period measured was half of the real period.
I, irr irregular brightness pattern, irregularly varying.
lp long period.
min the period has been measured on the minima in brightness.
N? the counted number of maxima is uncertain.
ph photographic observation.
pm primary maxima.
qm quadruple maxima: four maxima in one period.
R regularly varying
S the brightness did not (or only very slightly) change,
except for the variation caused by the change of phase-angle.
sa small amplitude : there is a small difference in brightness between
a maximum and a minimum.
sf short flashes, possibly used as maxima.
sm a relative (secondary) maximum occured between two absolute
ssm some secondary maxima were visible.
tm triple maxima: three maxima in one period.
u an observation made with the unaided eye.
var varying (usually used in the phrase 'slowly var').
vm the observed maxima varied in brightness during the observation.
It is possible that even other abbreviations were used. If you would notice
an abbreviation which is not in this list, please report this.
To describe the peculiarities of the flash-pattern (without drawing figures),
the following symbols are put into groups depending on the pattern observed:
A smooth primary (or absolute) maximum.
a like 'A' but secundary or relative.
F sharp (like a flash) primary (or absolute) maximum.
f like 'F' but secundary or relative.
M flat primary (or absolute) maximum.
m like 'M' but secundary or relative.
_ or - indicates a minimum or the absence of a (expected) maximum.
' the apostrophe usually indicates the maximum on which was counted.
Sometimes used with _ or - to indicate that the minima were
, the comma indicates the location of the minimum which was used to
count the periods.
Some examples are given below:
A'A' a regularly varying object with primary maxima only.
A'aA' a regularly varying object with secundary maxima. Primary maxima
were used to count.
A'FA_A' this pattern occurs very frequently in case of Soviet A2-
rockets. A maximum is followed by a flash (comparable in
brightness), by another maximum, after which the next flash is
absent. After this, the pattern is repeated.
A'fA_A' the same as the previous one, but the flash is less bright.
a'Fa_a' in this case the flash is definetely brighter than the smooth
M,M a pattern with two flat maxima divided by a sharply defined
minimum (which was used to count the periods).
F'F' a pattern which has flashes only.
7. Observers of the PPAS
AB A.C. Beresford Adelaide Australia
AF Alain Figer Martigues, Paris France
ANO Antero Olkkonen Ristiina Finland
AP Alphonse Pouplier Wepion Belgium
AR Alberto Rango Livorno Italy
AS Alexander Seidel Lemgo FRG
Stade/Elbe FRG, from 1983 on
BB Bjorn Bonny Eernegem Belgium
BD Bram Dorreman Achel Belgium
BDP Bart De Pontieu Oostende Belgium
BG Bill Gates Albuquerque, New Mexico USA
BJG Bjoern Gimle Junibacken Sweden
BK Bertus Kroon Apeldoorn The Netherlands
BP Bengt-John Piolon Oostende Belgium
BPW Bruce P. Watson Denver USA
BV Boris Vrancken Oostende Belgium
BY Brad Young Tulsa, OK USA
CE Christopher Engelhardt Fulda FRG
CS Christian Steyaert Geel Belgium
CT Cal Tech California USA
CW Chris Wyatt Bendigo, Victoria Australia
DA A. d'Allessandro Genua Italy
DAP David Alan Pickup Edinburgh Scotland
DB David M. Brierley Manchester Great-Britain
DC Dirk Carlens St.Lambrechts-Herk Belgium
DG Doyle J. Groves Noblesville, Indiana USA
DH David Hopkins Great-Britain
DIB Dietmar Buettner Chemnitz Germany
DJL D.J. Lazlo Denver, Colorado USA
DK Daniel Karcher Wittenheim France
DL Dirk Laurent Mechelen Belgium
DM Harry De Meyer Sint-Kruis, Brugge Belgium
DMB David M. Brierley Colorado Springs USA
DSB Douglas Biggerstaff Toronto Canada
DW D. West Austin, Texas USA
DWB David W. Bishop Utica, New York USA
EC Ed Cannon Austin, Texas USA
EL Ed Light Lakewood, NJ USA
EN Elisabeth Nuyts Kessel-Lo Belgium
ER Eero Rantalaiho Varkkala Finland
EV Eric Vondra Wampum, PA USA
FD Frank Dempsey Ajax, Ontario Canada
FF Franco Foresta Palermo, Sicily Italy
FR Frank Reed Scottsdale, Arizona USA
FV Fritz Verhelst Ekeren, Antwerpen Belgium
FW Frank Weissferdt Selters FRG
GAR Greg Retzlaff Saskatchewan Canada
GH Gary Holahan Silver Spring, Maryland USA
GL Ulrich Gentzel-Lingner Heidelberg FRG
GM Gunter Monz Peterberg Germany
GR Greg Roberts Kaapstad South-Africa
HB Hermann Boehnhardt Rodental-Moenchreden FRG
HK Horst Koehnke Stade-Elbe FRG
HS Hermann Schnitzler Grevenbroick FRG
HVB Hendrik Vandenbruane Beernem Belgium
IL Inge Leyssens Edegem Belgium
IPO Ian Porter Australia
JA Jan Aelbrecht Belgium
JC Johan Claes Oostende Belgium
JDW Jean De Weerdt Gistel Belgium
JDG Don Gardner
JEV Jim Varney Sacramento, California USA
JG Jason Gibson Melbourne Australia
JH Johan Hoste Oostende Belgium
JHR Jay H. Respler Freehold, New Jersey USA
JL Jean Lecacheux Meudon France
JM Jean Meeus Kessel-Lo (till 67-06-30) Belgium
Erps-Kwerps (fr 16-07-68) Belgium
JN Jim Nix Memphis, TN USA
JO J. Oudman Groningen The Netherlands
JOP Joel Piraux Marseille France
JP John Prentice Albuquerque, New Mexico USA
JPH Jason Hatton Strasbourg France
JR J. Ruland Hasselt Belgium
JR Juergen Renn Moers FRG
JS Jan Strobbe Eernegem Belgium
JSC Jim Scotti Tucson, AZ USA
JV Jaap Veltekamp Vries The Netherlands
Groningen The Netherlands
JVB Jan Vandenbruane Beernem Belgium
JVS Jan Vansteelandt Leuven Belgium
JVW Jeroen Van Wassenhove Nazareth Belgium
JW Joel Weisberg Albuquerque, New Mexico USA
KAH Kai Hamalainen Lappeenranta Finland
KB Ken Boedt Oostende Belgium
KD Kurt Dequick Bredene Belgium
KDL Kris Delcourte Belgium
KH Kevin Hestir Albuquerque, New Mexico USA
KJ Kurt Jonckheere Oostende Belgium
KO Kurt Osaer Bredene Belgium
KVG Karin Van Genegen Mortsel Belgium
LA Georges Lauwers Zemst Belgium
LB Leo Barhorst Ede + Alkmaar The Netherlands
LG Lloyd R. Gibson Thallon, Queensland Australia
LL L. Langeville Brussels Belgium
LP Lieven Van Parijs Meulebeke Belgium
LR Leo Rajala Jamsa Finland
LS Lutz Schindler Braunschweig Germany
LW Leo Wikholm Helsinki Finland
MA D.C. Mason Tremadoc,Caernarven,Wales Great-Britain
MAD Madison USA?
MAG Mauritz Geyser South-Africa
MD Alistair Macdonald Toronsville Australia
MF Matthew Francey Mississauga, Ontario Canada
MJ Michel Jacquesson Sevigny-Waleppe France
MM Mike McCants Austin, Texas USA
MO Marc Moors Bonheiden Belgium
MR Mike Rosseel Belgium
MS Markku Siljama Mantyharju Finland
MVP Michel Van de Putte Ronse Belgium
MZ Grupo Espacial Mendoza Argentina
NB N.J. Budd UK
NC Neil Clifford Oxford UK
PA Peter Aneca Bredene Belgium
PC Patrick Carpreau Mechelen Belgium
PDV Patrick Devreese Moen Belgium
PEW Peter Wakelin Ascot, Berkshire UK
PIA Pieter Audenaert Gent Belgium
PK Petteri Kankaro Merimasku Finland
PM Paul Maley Houston, Texas USA
PN Pierre Neirinck Malo-Les-Bains France
PP Pieter Passchijn Eernegem Belgium
PR Paul Roggemans Mechelen Belgium
PS Patrick Schmeer Saarbruecken-Bischmisheim Germany
PW Patrick Wils Niel Belgium
RD Rudy Dequick Bredene Belgium
RE Russell Eberst Edinburgh, Scotland Great-Britain
RGL Ron Lee Falcon USA
RIK Richard Keen Coal Creek USA
RK Rainer Kracht Elmshorn Germany
RM Rob Matson Belmont Shore, CA USA
RMC Ralph McConahy Barstow, CA USA
RO Jean-Pierre Rohart Wormhout France
RS Robert Sheaffer San Jose, CA USA
RW Ron Welch Watson Australia
SA Sacramento California USA
SL Stefan Lobet Kontich Belgium
ST San Antonio California USA
SW Sue Worden USA
TC Tristan Cools Brugge Belgium
TD Tommy Deslijpere Oostende Belgium
TH Terre Haute France
TID Tim Daniels Edegem Belgium
TK Takeshi Kawabata Yokohoma Japan
TR Tuomo Roine Helsinki Finland
TT Tuomas Torronen Espoo Finland
VAG Vince Gardiner Australia
VB Isi Van den Broeck Londerzeel Belgium
VC Paul Van Cauteren Aartselaar Belgium
VG Vincent Gathot Eernegem Belgium
VH Luc Vanhoeck Puurs Belgium
VI Van Iseghem Sint-Kruis, Brugge Belgium
VL Frans Van Loo Itegem Belgium
VM Veikko Makela Helsinki Finland
VN Van Nuys Belgium
WD Werner Depoorter Halle-Zoersel Belgium
WH Wim Holwerda Loon-op-Zand The Netherlands
WJW William J. Welker Pittsburgh USA
WN Walter Nissen Silver Spring USA
WPK Willie Koorts Wellington South Africa
WV Willy Verhaegen Wetteren Belgium
YY Yoshiro Yamada Yokohama Japan
(As of 1999,)
In total 166 observers produced 48648 observations. If possible the location of
the observations has been given. Some observers have moved or made observations
on a vacation trip. There is one double identification i.e. the initials JR are
the same for Juergen Renn and J. Rulandt (both made one observation)/
There are a few unidentified observers, whose names have been lost. None have
made more than a couple of observations.
Half of the observers have made less than 50 observations. Some of those are not
very experienced, which might influence the quality of the observations.
More than 50 observers are active at this moment. An asterisk '*' is given
next to the name of the active observers. All satellite observers are warmly
encouraged to join our group.
6. Use of PPAS
The PPAS is free of charge. It is updated regularly with new observations. The
updates are available from the same archive as where you find this text.
For more information contact the address below.
If you happen to notice errors, please report them. Also, all users are
invited to send their own observations (in the PPAS-format) to us.
All information on future versions of PPAS will appear on SeeSat-L and on
the www-pages of the Visual Satellite Observers Home Page.
It may be interesting to note that the BWGS has developed a software package
(SatFlash) which facilitates analysis of the PPAS data.
The PPAS-data may be used for scientific analysis, provided the source
You can find more information about the Belgian Working Group Satellites
on the Visual Satellite Observers Home Page: