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FPAS Reports - Specifications
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FPAS Standard Reports
(Fine Position of Artificial
Satellites)
(v1.2.1 - satflare.com)
Aug 16, 2012
The FPAS is a flexible standard for reporting, collecting and transmitting data related to:
Flaring Position of Artificial Satellites
Flashing Position of Artificial Satellites
Fading Position of Artificial Satellites
Full Position of Artificial Satellites
The
main aim of FPAS reports is the
transfer through a
compact line of text of all the data related to an observed event that
allow analysts
to quickly
model satellites,
easily and at any time after the reported event. The
format of the report is conceived to accommodate accurate and
detailed data produced by experienced observers during planned
observations, as well as approximate and rough data of accidental
observations which may be provided by casual observers. The
report
is mainly intended for modelling both stabilized satellites, which generate flares,
and tumbling satellites, which generate flashes,
for both LEO and GEO objects. However, the report can also carry data aimed to
positional measurements, orbit determination, and satellite
identification.
The position of the observed flare can be specified in the report
stating either the coordinates or the event time.
Coordinates are usually not suitable for GEO satellites but they may result more
accurate than time in case of accidental observations of LEO satellites
(for accidental observations it is easier to remember the satellite
position among stars rather than readily read a reliable clock). An
observer, should state in the report only the raw registered
information, which can be either coordinates or time (or both of them),
but
they should not derive time from position or position from time through post
elaborations
or
simulations.
The report should be published by the observer and,
successively, collected and archived by a collector. The
collector
can fill some reserved or optional fields with the aim to
complete
or improve the report. In some cases, the collector can even rewrite
the report in order to remove errors (the overall data of a complete
report is
redundant). In this latter case, both the original and the rewritten
versions have to be archived using the correct observation ID.
The report consists of a line (see note 1) containing a list of comma
separated
fields of variable length. The main rules are:
- An optional
field can be left blank writing a dash (-) in it.
- Decimal values have to be expressed with the dot (.) as decimal separator.
- Spaces are not allowed except in Auxiliary, TLE and Remark fields.
- Characters with a given meaning has to be reported as shown in this document, respecting lower/upper case
- Return
carriages are allowed only before Observation Info, Auxiliary, TLE 1,
TLE 2, and Remarks fields, to improve readability (see note 1)
The report is
composed by the following fields:
- FPAS12
- Each report
must start with the token FPAS12 (fixed
field, upper case) in order to allow programs to easily detect FPAS
reports in documents. The last two digits represent the standard version.
FPAS12 refers to FPAS standard version 1.2
- Satellite Catalog Number
- This field specifies the Norad number of the
satellite using always 5 digits. E.g. for Vanguard 1 this
field will contain 00005.
If the flaring satellite was not identified, write 00000.
The collector can fill this field later, generating a Z ID version.
- Extended Reporter/Station ID
- Composed by 6 characters:
- A character that specifies the source
of the report:
- R : original version
reported by the observer (report to be archived by the
collector)
- G : report generated by someone who
is not the observer nor the collector (it can be archived by
the collector)
- X : report is just
a temporary example or a demonstration (it is NOT intended to be
archived by the collector)
- Z : collector's reviewed
version. Must be generated only when some fields of the R or G versions
have been overwritten
by the collector. (it has to be archived by the collector)
- Initial character of the reporter's
first name (upper case)
- Initial character of the reporter's
surname (upper case)
- Last digit of the reporter's year of birth (e.g. an observer who was born in 1975 will write the number 5)
- Last digit of the reporter's day of birth (e.g. an observer who was born on the 27th will write the number 7)
- Report sequence of the day: write A for the first report, B for the second, and so on... After reaching Z,
the sequence restarts from A
Note: If the observer has a COSPAR ID, characters 2,3,4,5 can be replaced with the 4 digits of the COSPAR ID.
In this case the observation will be assigned to the station rather
than to the observer. Consequently, the 6th character should represent the
report sequence of the station for that observing day.
Example: The second report of the day for Mario Rossi, born on 27th of
July 1975 will be RMR57B
- UTC Date (of observation)
- Composed by 6 digits indicating year, month and day. E.g. the 16th of
May 2012 will be:
20120516
- UTC Time (time of
the flare maximum).
- This field can state the time of the observed flare using one of
the following formats:
- A string of 4 digits
indicating hour and minute. E.g. 22:45
UTC will be:
2245
- A string of 6 digit indicating hour,
minute and second. E.g. 22:45:31 will be:
224531
- A string of 8,9 or 10 digits indicating hour,
minute, and fractional seconds up to 1/1000. E.g 22:45:31.714 can be reported depending on the accuracy as:
- 224531.7
- 224531.71
- 224531.714
- Time Uncertainty
- This field states the uncertainty
of time
measurement. Three formats are allowed:
- uncertainty in seconds followed by a 's'
(lower case without spaces). E.g. 0.5 seconds will be: 0.5s
- uncertainty in minutes followed by a 'm'
(lower case without spaces). E.g. 1 minute and 30 seconds will be: 1.5m
- uncertainty expressed as MX corresponding to M*10E(X-8) s. E.g. 0.5 seconds will be 57
Note. The 3rd format should be used only if necessary (E.g. quick conversion of IOD reports)
- Derived UTC Time and Uncertainty (time
of the flare maximum) - This field is for the collector only
- Observer leaves it blank
- This
field can be completed by the collector when processing the reports in
order to assign a more accurate flare time using positional
data. This field must contain both time and uncertainty separated by a dash (-). The allowed formats are those for UTC Time and Time Uncertainty fields. E.g. 224532.71-0.01s
- Observer's Latitude (WGS84)
- Latitude is stated as decimal degrees North
up to 5 decimals (e.g. 34° 15' S will be stated as -34.25)
(Future formats may be accepted in further extensions of the standard)
- Observer's Longitude (WGS84)
- Longitude is stated as decimal degrees East
up to 5 decimals (e.g. 116° 45' W will be stated as -116.75)
(Future formats may be accepted in further extensions of the standard)
- Observer's Altitude - (WGS84) Optional
- Altitude of the observer's location in
meters. If the observer does not enter the altitude this field should
contain a dash (-).
- Observation Info
- Composed by a string of 4 characters:
- This character specifies the type of
event and it can be either:
- L : the event was a flare
- F : the event was a flash
- A : the event was an
anti-flare (marked brightness decrease)
- V : the event was a brightness/colour variation/behaviour
- S : the document reports a steady behavious in brightness
- P : this report provides only positional data (e.g. request for identification)
- This character specifies the type of
observation and it can be either:
- P : Predicted event (the
observation of this event was planned and the event was expected)
- U : Observed/Unpredicted event (the
observation of this satellite was planned but this event was not
expected)
- S : Spotted during an
observation of other objects
- A : Accidental (this event was
observed accidentally, no observation was being performed)
- k : Unknown
- This character specifies how the event
has been captured, and it can be either:
- R : Recording (E.g.
all-sky camera)
- k : Unknown
- This character specifies the observing
conditions and it can be either:
- E : Excellent (no Moon/clouds,
great seeing, minimal air/light pollution)
- G : Good (no Moon/clouds,
conditions could be better, but not much)
- F : Fair (young/old Moon, some
air/light pollution making fainter stars invisible)
- P : Poor (gibbous Moon, haze, more
air/light pollution making more stars invisible)
- B : Bad (bright Moon, air/light
pollution, some clouds; difficult)
- T : Terrible (bright Moon,
air/light pollution, looking through clouds)
- k : Unknown
- Satellite Movement - Optional
- This field
specifies the apparent movement of the satellite during the flare. If
this field is filled it has always to contain 3 characters:
- This character specifies the perceived speed of the satellite:
- G : No movement perceived (Geostationary)
- W : Only a slight movement perceived, very slow ( < 0.1 deg/s)
- S : the satellite was moving slowly (around 0.2 deg/s)
- R : Regular flare, usual speed (around 0.5 deg/s)
- F : the satellite was moving fast (around 1 deg/s)
- T : the satellite was moving extremely fast (> 1.5 deg/s)
- k : Don't know
- This character specifies the satellite direction:
- U : Up
- D : Down
- L : Left
- R : Right
- N : North
- S : South
- E :East
- W : West
- k : Don't know / Not Given
- This character is used to correct the direction
stated in 2. The same list of characters (U,D,L,R,N,S,E,W,K) can be used.
Lower Case means just a slight correction.
Example 1: A
satellite fast moving toward North-East will be coded as: FNE
Example 2: A
satellite slowly moving toward North with a slight deviation toward
East will be coded as: SNe
- Duration of the Observation
- This field specifies how long the satellite was observed. Three formats are allowed:
- duration in seconds followed by a 's'
(lower case without spaces). E.g. 2.5 seconds will be: 2.5s
- duration in minutes followed
by a 'm' (lower case without spaces). E.g. 3 minutes and 30 seconds
will be: 3.5m
- duration expressed as MX corresponding to M*10E(X-8) s. E.g. 5 seconds will be 58 (use this format only if needed)
- k : dont know
- Duration of Flare / Single Flash / Event
- This field specifies how long the magnitude
of
the satellite was close to the value reached at the event peak.
Three formats are allowed:
- duration in seconds followed by a 's'
(lower case without spaces). E.g. 2.5 seconds will be: 2.5s
- duration in minutes followed
by a 'm' (lower case without spaces). E.g. 3 minutes and 30 seconds
will be: 3.5m
- duration expressed as MX corresponding to M*10E(X-8) s. E.g. 5 seconds will be 58 (use this format only if needed)
- k : don't know
- Satellite Minimum Magnitude (maximum brightness)
- This field specifies the maximum brightness reached by the satellite within the interval Duration of Flare / Single Flash / Event using one of the following formats:
- Absolute magnitude. E.g. for a very bright iridium flare could be -8
- Variation of magnitude.
If the observer did not estimate the absolute magnitude, its
variation can be specified instead. In this case the value has be
expressed with a v prefix and the field Maximum Magnitude has to contain K.
> Example. If the flare consisted of an increase of 2 magnitudes, this field can contain: v2
- k : unknown (this option should be used only when the magnitude variation of an anti-flare is specified in the next field)
- Satellite Maximum Magnitude (minimum brightness)
- This field specifies the minimum brightness reached by the satellite within the interval Duration of Flare / Single Flash / Event using one of the following formats:
- Absolute magnitude. E.g. for a very iridium immediately before the flare could be 4
- Variation of magnitude. If the observer did not estimate the absolute
magnitude, its variation can be specified instead. In this case the
value has be expressed with a v prefix and the field Minimum Magnitude has to contain k.
> Example. If an anti-flare consisted of a decrease of 1.5 magnitudes, this field will contain: v1.5
- inv: insert the 3-char string inv if the satellite reached invisibility
- k : unknown
- Observation Details - Optional
- This field is either blank or composed by of 7 characters that specify some details about the observation:
- This char specifies how the magnitude at the flare peak were estimated:
- G : the magnitudes were estimated by experience
- I : the magnitudes were roughly estimated with indirect comparison (not seen both objects simultaneously)
- D : the magnitude were estimated with direct comparison (seen both objects simultaneously)
- k : don't know / don't pertinent
- This char specifies the magnitude uncertainty of the flare peak
- 1 : uncertainty 1 mag
- 2 : uncertainty 2 mag
- 3 : uncertainty 3 mag
- 4 : uncertainty 4 mag
- B : uncertainty > 4.5 mag
- H : uncertainty 0.5 mag
- F : uncertainty 0.2 mag
- T : uncertainty 0.1 mag
- k : don't know / don't pertinent
- This char specifies if the event was observed with interruptions:
- C : the observation was Continuous with no interruptions - all events within the observation window could be observed
- I : the observation was Interrupted - some events may have been missed within the observation window
- S : the observation was Shortly interrupted - however no event could have been missed
- k : don't know / don't pertinent
- This char specifies whether the peak of the event was observed:
- C : the flare peak / brightest flash occurred in the observation window and was observed
- M : the flare peak / brightest flash occurred in the observation window but it was missed due to interruption
- B : the flare peak occurred
before the observation / the brightest flash may have occurred
before the observation window
- A : the flare peak occurred after the
observation / the brightest flash may have occurred after the
observation window
- k : don't know / don't pertinent
- This char specifies the prefix for the colour of the flare. It can be either:
- N : None
- L : Light
- I : Intense
- k : don't know / don't pertinent
- This char specifies the colour of the flare.
- N : Neutral (White)
- R : Red
- B : Blue
- Y : Yellow
- G : Green
- X : None of them (describe the colour in
the Remark field)
- k : don't know / don't pertinent
- This char specifies the use of the auxiliary field. For this standard version it can be only :
Example: DHCBNR reads: the magnitude of the
flare was estimated by directly comparing brightness of satellite and
stars with uncertainty of 0.5 magnitudes. The observation was
continuous (no interruptions) however only the final part of the flare
could be observed since the observation started too late. The color was
red.
- Format of positional data
- This field specifies which type of format
is used to report the satellite position at the flare time. It can be
either:
- N : No position was taken by the
observer
- R : Position is stated by means of RA
and DEC (decimal degrees)
- A : Position is stated by means of AZ
and EL (decimal degrees)
- 1 to 7: Position is stated by means of the IOD formats - See IOD standard for details. (Use this format only if needed)
- E : Position is state by means of AZ and EL (AZ specified through cardinal points, EL in decimal degrees)
- S : Position is approximately stated by
indicating the name of the nearest star
- C : Position is stated as in C but the
star
is identified by indicating constellation abbreviation and the
star grade
within the constellation (example: Leo Alpha). It is possible to keep the star name blank if the star was not identified.
- Z : Position was not stated by the
observer but it was successively added by the collector using the
format type A
- Satellite Position (coordinate
1) - Optional
- This field specifies the first coordinate
of the satellite position depending on the format chosen
in Format of positional data:
- N : this field is left blank (dash)
- R : this field contains the right
ascension
coordinate (RA) in decimal hours up to 4 decimal digits. E.g. 12h 35m
10s will be: 12.5861
- A : this field contains the azimuth (AZ)
in decimal degrees up to 4 decimal digits. E.g. 225.5° will be 225.5
- 1 : this field contains RA expressed in the format: HHMMSSs
- 2 : this field contains RA expressed in the format: HHMMmmm
- 3 : this field contains RA expressed in the format: HHMMmmm
- 4 : this field contains AZ expressed in the format: DDDMMSS
- 5 : this field contains AZ expressed in the format: DDDMMmm
- 6 : this field contains AZ expressed in the format: DDDdddd
- 7 : this field contains RA expressed in the format: HHMMSSs
- E : this field contains the azimuth specified using the cardinal
points with 2 characters. The first one set the position and the
second one correct or remark the position. Lower case can be used for
the second character to slightly correct the first one. The
allowed characters are:
- N : North
- S : South
- E : East
- W : West
- k : Unknown / Not Given / None
- Examples: NE for North-East, Ne for North-North-East, NK for roughly North, NN for Exactly North.
- S : this field contains the name of the
star. E.g. Vega
- C : this field contains the grade
of the star within its constellation or it is left blank if the star is not known. E.g. Beta
- Z : the same as in type R.
if you don't know the uncertainty leave the field blank (-)
- Satellite Position (coordinate 2)
- Optional
- This field specifies the second coordinate of
the satellite position depending on the format chosen in Format
of positional data:
- N : this field is left blank (dash)
- R : this field contains the declination
coordinate (DEC) in decimal degrees up to 4 decimal digits. E.g -12°
34' 15" will be: -12.5708
- A : this field contains the elevation (EL)
in decimal degrees up to 4 decimal digits. Eg. 45.3° will be 45.3
- 1 : this field contains DEC expressed in the format: +DDMMSS
- 2 : this field contains DEC expressed in the format: +DDMMmm
- 3 : this field contains DEC expressed in the format: +DDdddd
- 4 : this fileld contains EL expressed in the format: +DDMMSS
- 5 : this field contains EL expressed in the format: +DDMMmm
- 6 : this field contains EL expressed in the format: +DDdddd
- 7 : this field contains DEC expressed in the format: +DDdddd
- E : the same as in A
- S : this field is left blank (dash)
- D : this field contains the abbreviation of
the constellation name (3 characters). E.g. Scorpius will be
Sco
- Z : this field contains the same
data as in type R.
- Position Uncertainty - Required
only if Satellite Position is stated
- This field specifies the uncertainty in the
position determination and it depends on the Format chosen in Format
of positional data:
- N : this field is left blank (dash)
- A,B,C,D,Z : this field contains
the accuracy in decimal degrees up to 4 decimal digits. E.g.
3° will be 3
- 1,4 : uncertainty expressed as MX in seconds of arc as M * 10E(X-8)
- 2,5 : uncertainty expressed as MX in minutes of arc as M * 10E(X-8)
- 3,6,7 : uncertainty expressed as MX in degrees of arc as M * 10E(X-8)
if you don't know the uncertainty leave the field blank (-)
- Auxuliary Information - Optional
- This field is not yet used. Keep this field blank putting a dash (-)
- TLE Line 1 - Optional
for the observer, Mandatory for the collector
- This field contains either:
- the Line 1 of the TLE
whose epoch best fits the observation time
- the Epoch of the TLE that best fit the observation time
- TLE Line 2 -
Optional for the observer, Mandatory for
the collector
- This field contains the Line 2 of the TLE
whose epoch best fits the observation time (only if the TLE Line 1 contains the first line).
- Remarks - Optional
- This field may contain some remarks or
comments that may help to analyze the report (spaces are allowed).
- The report ends with a
semi-column (;)
Note 1. The report is intended to be transmitted over a single text line,
however, to improve the readability of reports with embedded TLE a
carriage return is allowed before TLE Line1, TLE Line 2 and Remarks, as
shown by the following examples:
Example of FPAS report without TLE:
FPAS,25777,XMR53A,20120806,192347,1s,-,45.31,8.23,100,FPUF,RNN,3m,5s,-2,5,G1CCLNN,N,-,-,-,-,-,-,-;
Example of FPAS report on multiple lines with embedded TLE:
FPAS,25777,XMR53A,20120806,192347,1s,-,45.31,8.23,100,FPUF,RNN,3m,5s,-2,5,G1CCLNN,N,-,-,-,-, 1 25777U 99032A 12217.18427485 .00000253 00000-0 53886-4 0 493, 2 25777 86.5092 247.0803 0002459 85.9061 274.2430 14.54936516698260, Example of report;
Collecting and identifying reports:
Each report can be uniquely identified in a Database (or simply
referred to) by the unique 18-character key obtained by joining the
following fields:
- Extended Reporter/Station ID
- First 4 digits of the UTC Time
Example of Key that identifies a
flare report: XMR53A201208061923
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