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Paramount ME Non-sidereal Tracking RatesHow to Configure the Paramount ME to Track Objects Moving at Non-sidereal Rates
Working Examples:
Comet TrackingFor our example we will use the Paramount ME to track on Comet 9P/Tempel. First use TheSky6's Data > Comet & Minor Planets command to obtain the most recent orbital elements for the comet. This is best done the same day you will be imaging if and whenever possible. For objects with very stable orbits you need not be so concerned, i.e. the brighter more stable minor planets..
In TheSky use the option Data > Comets & Minor Planets and click on the Comets tab. (Select and remove the existing comets.) Those listed (if any) will most likely have out-of-date orbital elements! Best to start with a "clean" slate. See below.
A page with details on what sources TheSky uses for current "orbital elements" can be found here!
Drag the entire list of existing comets and choose the "Remove" button on the Comets and Minor Planets dialog as shown. Remove any existing comets Click Yes when asked to confirm removal. Once the existing comets have been removed click the Observable button in the From the Web group. Data > Comets and Minor Planets You are now presented with a list of comets that are considered currently visible. You can either choose to DRAG the entire list with your mouse or simply click on the one(s) that you want. If you use CONTROL+Mouse Click you can individually select more than one. Select more than one Pick the ones you want, or highlight all of them with a mouse drag down the entire list then press OK to add them to TheSky.
NOTE: Keep in mind that many of these comets are very faint and may not be visible with your equipment. BECAUSE the magnitude does not exist until it has been computed by TheSky using the orbital element data TheSky cannot simply filter out the faint ones for you yet. Once downloaded into TheSky you can use the filtering option to set any magnitude range you like. Use the Display Explorer to "name" the comets and also set a filter to hide the fainter ones. View > Display Explorer By typing in "COMET" in the GO to: box you are taken directly to the entry for COMETS. The Display properties allows you to enter a magnitude cut-off. Actually you can "FILTER" them by the starting magnitude and the Display Properties for Comets Now only the brighter comets will be displayed greatly cleaning up the display. Next Label the comet with either the "name" and/or magnitude to make it easy to see. Under the Display Properties for Comet check mark Common Name and/or magnitude as shown. Check name Make sure that you have the Common Names set to visible or they will not show. Use View > Labels and make sure that Common Names is checked as shown. Turn on Common Name labeling Now the comets will be labeled on the display. Comet Labeled with magnitude In order to Find Comet 9P/Tempel in our example choose
Edit > Find then use the Find dialog. You can either go down under
Solar System > Comets to see the entire list (only a few shown here for
clarity) OR you can enter the name in the find as in Find "9P/Tempel"
without the quotes. NOTE: By choosing the comet from the list you will not have to enter the name manually which assumes you know the spelling. By entering a name in the find dialog you will have to know how the comet is labeled and enter this correctly. Using the list is not prone to input errors when searching for you query! Use the Find dialog Now that you have the orbital elements loaded in TheSky can accurately compute the tracking rates for both RA and DEC for the given date and time! After you have slewed the telescope to the object use the Telescope Tab on the object Information dialog to set the tracking rates. There is a button "Set Tracking Rates". When this is clicked you will be shown the current RA and DEC rates in arcseconds/second. This is a great reality check
WARNING: These computed rates are completely dependent on the Site information in TheSky (Data > Location) AND the accuracy of the orbital elements used. Basically garbage in garbage out. ALWAYS check the site information along with the DATE and TIME! Example for Table Mountain Observatory Also make sure your date and time along with the daylight option have been properly set! Choose the wrong daylight option can cause an error of 15 degrees or 1 hour. Let TheSky compute the tracking rates from the
orbital elements As a reality check take a long exposure or several 1 to 2 minute exposures over say 15 minutes. If the tracking rate is correct the comet will stay fixed and the stars will trail slightly because of the rate change! Minor Planet TrackingMinor Planet tracking is almost identical to tracking comets. First you want to get the most recent orbital elements you can. This can usually be done from directly within TheSky! Use Data > Comets & Minor Planets and choose the Minor Planets tab. The following shows how to get a list of the MPC's "Distant" minor planets. You can also pick from the "Critical" and or "Unusual" list as well. Data > Comets & Minor Planets
> Minor Planets Next just grab the minor planet(s) you are interested in just like the comet example above. You can drag the mouse over the entire list or simply CONTROL+Mouse Click on the individual ones you are interested in. Once the minor planet has been added you can use the Find dialog to search for it by name or by clicking on the list. See below example for Chiron. Find Dialog Once TheSky has found the minor planet for you after you have slewed to the object you can have the Paramount track at the minor planet rate. Use the option Set Tracking Rate as found on the object Information dialog. Set rates to match minor planet Now the minor planet will stay centered and the stars will trail over time. Click here to see an example of the Paramount ME tracking at 1 arcseconds/second! on a fast NEO's! Tracking Satellites - ISS, Iridiums and More
To track on a satellite first issue a Slew To when you have found it or clicked on it in TheSky then use the option "Track Satellite" on the telescope tab. See below.
Tracking satellite NOTE: Tracking a satellite is not as simple as a planet, comet, or minor planet. It will take one or more slews to get the object in the field then it TheSky will attempt to micro-slew to the object based on the changing rates in RA and DEC. Note rates are displayed The star symbol in the center represents the center of the field and the smaller circle where the scope is relative to the target. When the two are coincident the object is being precisely tracked!
You can also use a spiral search using Start Search whereby the scope will attempt to find the object if it is no where in the field. If the object is in the field but offset from center you can mouse click inside the square box and the object will be offset from the current position in the opposite direction. Takes practice! This way you can manually center the satellite provided it is in your field. If not try to search for it a second time and make sure you are setting the rates to match the bird. Good luck!
Before trying to nail a fast moving bird first make the tracking work with a Geosynchronous orbit satellite. Why? Because they hardly move at all! These are quite easy and fun. In fact you can actually just turn the tracking off completely and these satellites will remain in the field. Even in very small CCD fields. See below image. Four Geosynchronous Satellites in a Single Photo4 Geos all in a row! Weather satellites are also a very good for a first try since they too move very slowly. Iridium Flare Imaged by Tracking on the Iridium SatelliteThis Iridium 10 flare CCD imaged with C-14 and Paramount ME using an ST-9E. First attempt! The option to "Track Satellite was used and a 67 second exposure was taken. Note the trailing stars on the left of the image. You can see the satellite is moving reasonably fast! Tracking on Iridium 13 ST-9E C-14 image of
flare
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