A quick way to get started

Sec one- Quick way to go out and observe satellites, Free!

                Sec two- With a little investment of time and money

                                      Sec three- Advanced observing, a little more investment in time

Each topic is treated lightly here, some have links for more information, for even more in-depth information on the topic hit the VSOHP and its links. Regarding software and websites mentioned herein, these are things and sites that I use fairly often. There are many more excellent sites and softwares out there, and I intend no disrespect to them and their authors, this is a quick and easy guide put together quickly.  I plan on a more extensive list of
these things in the near future for the advanced observing section)

    ONE, TWO, THREE

One (free or almost free software)

    Go to Mike McCants site  or Satspy.com and download either Quicksat (Dos, Unix, Linux, Win95  DOS mode) or Satspy(Win 95).  If you don't want to clutter up your harddrive with yet another program  try Chris Peat's Heaven's Above Website.
Quicksat is freeware and outputs the azimuth and elevation of where the satellite will rise,
culminate in its pass and where it will set.  You might want to have a compass handy
for the azimuth and for elevation remember that 90 degrees is straight upand the horizon is zero!
Satspy gives you a thirty day free trial usage but unlike quicksat it will print out good star
charts showing the satellites pass in reference to the stars.
Heaven's Above will do it all online

      Whether you use a tracking program at home or Heaven's Above online site you will need to determine the latitude, longitude and elevation of your observation site. The Tiger map server of the US Census bureau will help you get a decent determination for casual observing.  More on how to get a better determination for making "measured" observations will be covered in section two.

Make sure that you set the correct GMT offset from your time zone for your location.

If you've downloaded a program , you'll need updated elsets to load into it.  I suggest Mike's site and download alldat.zip, classfd.zip and iridium.zip, again there are several other locations where
updated elements can be obtained.
.

-Alldat is 8000 or so satellites, boosters, deployment platforms, rockets and debris;
 -Classfd- are old and new element sets not available from Nasa's OIG,  it includes
satellites, boosters and rockets like DMSP's, NOSS's and Lacrosses,
(Defense Meteorlogic Satellite Program, Naval Ocean Survey Satellites, Radar Imaging satellites)
-Iridiums are the Iridium/Motorola communications satellites that flare so brightly
(Iridiflar, freeware, predicts where you can see these flares)).

    At Sat-tracks.com on the links page I update weekly (sometimes daily) an element set "Select.tle" that contains, Decaying objects, objects unavailable from OIG, BWGS priority objects, Iridium tumblers as well as general interest objects like ISS, Mir, Abrixas and Starshine and newly launched objects.

More Tracking Software
Other sites where elements can be obtained.
 

Go observe!

For objects to magnitude  3.0 or 4.0,  depending on the atmospheric conditions of your area, you can observe with the naked eye.  For 4.0 to 7.5 use binoculars and  for dimmer objects a four inch scope or larger would be fine, although serious observers use 8 inchers.  Magnitudes are not always "spot on", observing from out in the country side is better than from in the city or town.  Make sure you have an accurate timepiece that is set to the minute at least,  to the second is much better.

    GOAL- Run the software and observe the Satellites you are interested in.  Suggested
"unique" targets would include Ajisai, a NOSS trio, the two Lacrosses, TiPs, Mir,  ISS, and maybe an Iridium tumbler.  Ajisai requires binoculars and will appear to sparkle with three to four magnitude 4.0 or 5.0 flashes per second.  NOSS would also require binoculars although sometimes they have been observed by naked eye.  TiPs is definitely a binocular or telescopic target.  TiPs is two satellites connected by a tether and appears as a line moving against the stars. Iridium tumblers can be viewed by binoculars and by naked eye and will give very bright flashes.  You can check the Data pages at this site for estimated flash patterns.

Two (Intermediate to advanced observing)

    Ok you've observed a few interesting objects and feel some strange compulsion to measure RA, Dec and time the object passed through Hercules or where ever and want to post it at SeeSatL where the Satellite trackers post their observations.  Get Skymap, (Shareware) or a tracking program of your choice. Make sure that whatever software you use is employs good star charts
and can give you good Right Ascencion and Declination or Azimuth and Elevation data.  Skymap can use Tycho charts with objects to around magnitude 11.0. Again there are many to choose from but make sure they are compatible with the software you are using. Also get Obsentry, (Freeware) to format your data for posting, available at Sat-Tracks on the links page..
    You should also obtain  a stopwatch, a taperecorder, a Shortwave receiver, (capable of getting 5, 10, 15 or 20 MHz) and at minimum some 7 x 35 binoculars, (10 x 50's even better, or what the pros use something like 60-80 x 80-100's and a steady tripod to mount them on).  If you really want to get into it on a telescopic level, at minimum maybe a 3 inch telescope, or better yet, an  8 inch Dobsonian or bigger.

    Register your observation site, (determine your observation site's lat/ long and elevation to within 50 feet or better, a seven minute topographical map will help in this and it is more accurate than the Tiger Map Server. You can submit a request for a station number to  Russell Eberst at the Royal Observatory Edinburgh). Using your software of choice run predicted passes for the evening or morning.

What do you look for?

    Look for what you are interested in observing.  Hey its a free world, well mostly. You could also consider that there are analysts around the world who would appreciate data on particular satellites.  For example there are analysts interested in  tracking objects that aren't available from most public and governmental sources except through shared information available on SeeSatL. Many of these may not have been measured for a month or two, see below for methods to measure position. There are analysts who collect  BWGS priority object flash timings (or photometric periods see below for method). Check for passes of Abrixas or Starshine, there are analysts that would like to get flash timings of these objects.  In particular Starshine which will decay in mid February 2000 researchers are offering prizes for accurate observations.  You could also look for soon to re-enter objects, (decayers) there are analysts that would like to hear about these, in particular position, flash timings and magnitudes changes.  Also, look for recently lauched objects, see how accurately OIG is tracking them.  Look at ordinary objects and see whether they are flashing or changing in magnitude.  Often you will see objects pass that you are not looking for, its not a bad idea to make at least two position/time measurements.  Usually they are catalogued objects but sometimes you may discover a previously un-catalogued object.  Skymap can be set to identify the catalogued objects using the latest alldat.tle.

Position measurements

 Using Skymap or other program , look for a pair of stars ( a degree or less apart) that the target object will be passing between.  The more perpendicular the better.  Note the time of its passage using the stopwatch.  I usually start the stopwatch at the top of a minute before the predicted pass.  If the element set is old you might want to start the watch as much as five to ten minutes early and observe.  Some objects can be as much as five to ten minutes early or late, (some more so requiring some tweaking of the elements to create search elements more on this in step three).  Look for the satellite to pass between your target stars noting where it passes on an imaginary line between the stars.  Record your observation, noting the magnitude of the object as well.  This can be done by comparing it to nearby stars.
 After recording your observations run your software plot of the object and record the RA and Declination and time where it was observed.  With Skymap you can put the cursor on the observed location and then get a readout of RA and Declination.  Determine the error involved.  Usually five percent of the distance between stars, (5% of one degree would be three arcminutes).  The closer together the measuring stars the more accurate the observation. (5% of a half degree,30 arcminutes, is 1.5 arcminute).  Don't worry you can't get much more accurate than this using a telescope, most observations are within several arcminutes and .2 secs in time and greater using binoculars.
 More on Position measuring

Flash timings
Again using the stopwatch note the flashes or changing magnitude reflected from the target satellite and time them.  These can be reduced to a format usable by the BWGS.

Finally
Format your positional observations using obsentry and/or the BWGS format and submit your formatted observations to the SeeSat list.


 

GOAL- Time the passage of a satellite between two stars about a degree apart, format the data
and submit it to SeesatL.

Three (Advanced observing and analysis)

 Wow, you've been submitting some good observations.  Now get Fitelem or IOD (both freeware) and begin collecting observations posted by the other observers and begin generating your own elsets.  Learn what the element set is composed of from VSOHP and read T.S. Kelso's paper on the math behind the element set.  Creating accurate element sets is what its all about.
Rick von Glahn maintains a site for element manager ,his program for managing elsets, it also gives good graphics of what the orbits look like, compare components of different orbits.
For more information on "what" you are looking at try Mark Wade's Encyclopedia Astronautica.

Goal- Make observations of objects that others are tracking and using your observations and theirs create an  element set, and see how accurate it is.
OK, a search element is derived by varying the mean motion term of the elset to get search areas and times of passage of the target satellite. As another goal find an object with an old element set
six months or so and see if you can update it with observations.

Have fun!

Back to the Sat-Tracks Links page

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