Generating Asteroid & Comet Transient Catalogs for RTGUI

Beginning with RTGUI Version 8, it is no longer necessary for most users to use this page to download comet or asteroid positions. The program now performs that function effortlessly - all you do is give it the name of the object. However, there may be a small number of users who have a proxy connection to the internet, or have access problems with a firewall, and cannot use that new functionality. Those users must make Transient Catalogs for comets and asteroids the old way (which only takes a few minutes, anyway). Remember that it is perfectly possible to download transient catalogs to one computer, and copy them to another (they should be in the TransientCats directory below the RTGUI program directory).

This webpage, intended to access data from the Minor Planet & Comet Ephemeris Service at Harvard, allows the users of RTGUI to obtain elements for Comets and Asteroids, from which Transient Catalogs can be created. You should have already downloaded the small conversion program ephtortg (version 5 or later should be used - it will be consistent with the new informational format of RTGUI Ver. 8)

The options selected below are correct for RTGUI. You need only supply the object's name in standard astronomical terminology. The name does appear to be case sensitive, and it seems to like capital letters. To obtain current positions, do not change any other field. You may optionally specify a different start time, if you wish.

Comet names must begin with C/ for Comet (example: C/2002 T7) or P/ for Periodic Comet (Example: P/Halley). Asteroid names need not be preceeded by the number in parentheses (Example: (4) Vesta). If you leave out the comet designation (example: Halley), assuming you find anything at all it will be an asteroid, in this case (2688) Halley. Enter the name, then press "Get Ephemerides".

If the resulting page contains columns of numbers, wait for it to finish loading. Press Ctrl-a (selects all text), then Ctrl-c (copies text to clipboard). You can then use a text editor such as notepad to receive the text from the clipboard, press Ctrl-v. You will have 60 days' worth of positions in this file. If you want more positions, cut-and-paste the time of the final object position into the "Ephemeris start time" on this page, re-enter the name, and repeat. This gives another 60 days' positions. You can repeat this as many times as you want. Save the resulting file as a text file, with a filename of 8 characters or less (example: pallas.txt).

When your text file is finished, run ephtortg, and tell it your file name. It creates an output file of the same name as the input, with the extension .rtg . Afterwards you can change the output file name to anything you want, so long as it still has the extension .rtg (example: Pallas05_2004.rtg) .

If the resulting page contains an error notification instead of positions, the name that you entered was not valid.

Return ephemerides

Object Name: Enter a single Comet or Asteroid designation or name
(examples: Vesta ; C/2002 T7 ; P/Encke; (4179) Toutatis )

The "Ephemeris start date" here is optional. If left blank, the start date and hour is right now.

Ephemeris Options:

By default, ephemerides are geocentric, begin now and are for 60 days at 1 hour intervals. RTGUI Transient Catalogs must utilize hourly positions. 60 days (1440 hours) is the maximum data that can be requested in a single operation.

Ephemeris start date: Blank means "start now". You can also enter a date in the format 2004 05 21 00 .

Number of dates to output

Ignore everything below this line!

hours

decimal units


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This service utilises the Minor Planet Ephemeris Service,
courtesy of the IAU's Minor Planet Center,
and it has been made possible by Process Software Corporation,
and their excellent OpenVMS Web server, Purveyor.