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- .tr |
- .th AZEL VI 6/3/74
- .sh NAME
- azel \*- satellite predictions
- .sh SYNOPSIS
- .bd azel
- [
- .bd \-d
- ] [
- .bd \-l
- ] satellite1 [
- .bd \-d
- ] [
- .bd \-l
- ] satellite2 ...
- .sh DESCRIPTION
- .it Azel
- predicts, in convenient form,
- the apparent trajectories of Earth satellites
- whose orbital elements are given in the
- argument files.
- If a given satellite name cannot be read, an attempt is made to find it
- in a directory of satellites maintained by the
- programs's author.
- The
- .bd \-d
- option causes
- .it azel
- to ask for a date and read line|1 data (see below) from the standard
- input.
- The
- .bd \-l
- option causes
- .it azel
- to ask for the observer's latitude, west-longitude,
- and height above sea level.
- .s3
- For each satellite given
- the program types its full name,
- the date,
- and a sequence of lines each containing a time,
- an azimuth, an elevation,
- a distance, and a visual magnitude.
- Each such line indicates that:
- at the indicated time,
- the satellite may be seen from Murray Hill
- (or provided location)
- at the indicated azimuth and elevation, and that its distance
- and apparent magnitude are as given.
- Predictions are printed only when
- the sky is dark (sun more than 5 degrees below the horizon)
- and when the satellite is not eclipsed by the earth's shadow.
- Satellites which have not been seen and verified will
- not have had their visual magnitude level set correctly.
- .s3
- All times input and output by
- .it azel
- are GMT (Universal Time).
- .s3
- The satellites for which elements are maintained are:
- .s3
- .lp +10 10
- sla,b,e,f,k Skylab A through Skylab K.
- Skylab A is the laboratory;
- B was the rocket but it has crashed.
- A and probably K have been verified.
- .s3
- .lp +10 10
- cop Copernicus I. Never verified.
- .s3
- .lp +10 10
- oao Orbiting Astronomical Observatory.
- Seen and verified.
- .s3
- .lp +10 10
- pag Pageos I.
- Seen and verified;
- fairly dim (typically 2nd-3rd magnitude), but elements are extremely accurate.
- .s3
- .lp +10 10
- exp19 Explorer 19; seen and verified,
- but quite dim (4th-5th magnitude) and fast-moving.
- .s3
- .lp +10 10
- c103b, c156b, c184b, c206b, c220b, c461b, c500b
- .br
- Various of the USSR Cosmos series; none seen.
- .s3
- .lp +10 10
- 7276a Unnamed (satellite # 72-76A); not seen.
- .s3
- .i0
- The element files used by
- .it azel
- contain five lines.
- The first line gives
- a year, month number,
- day, hour, and minute
- at which the program begins its consideration of the satellite,
- followed by a number of minutes and an interval in minutes.
- If the year, month, and day
- are 0, they are taken to be the current date (taken to change at 6 A.M. local time).
- The output report starts at the indicated epoch and
- prints the position of the satellite
- for the indicated number of minutes
- at times separated by the indicated interval.
- This line is ended by two numbers
- which specify options to the program governing
- the completeness of the report; they are ordinarily
- both ``1''.
- The first option flag suppresses output when the sky is not dark;
- the second supresses output when the satellite is eclipsed by the
- earth's shadow.
- The next line of an element file is the full name of the satellite.
- The next three are the elements themselves
- (including certain derivatives of the elements).
- .sh FILES
- /usr/jfo/el/* \*- orbital element files
- .sh "SEE ALSO"
- sky (VI)
- .sh AUTHOR
- J. F. Ossanna
- .sh BUGS
-