RTGUI: Real-Time Interactive Windows Software for Astronomical Observers
Ver. 10 (Aug. 29, 2015):  User Interface Enhanced for Use on Windows Tablet PCs. see 
 What's new.

Easily Download Selected Comet and Asteroid Positions Via the Internet.
Quickly find Planets, Messier Objects, Caldwell Objects, NGC/IC Objects, Named Stars, Carbon Stars, Quasars, and > 2,500 Double Stars, by Constellation, Altitude, Magnitude, etc..

Fully-Updated NGC and IC data - errors in standard catalogs fixed.

RTGUI runs on Windows 8.1 Tablets - Can Call Skycharts. Very convenient to take out in the field!

Now with Scripting for Telescope Automation.

Read the FAQ - or - Find Out What's new -
Read or Join the Yahoo Group for RTGUI.
Astro Adventure Weekly's Youtube Video explaining how to use RTGUI.

RTGUI running on a Windows 8.1 Tablet, with Skychart

RTGUI running on a Windows 8.1 Tablet, with Skychart. It runs on any PC on any standard version of Windows (not "Windows RT" or "Windows CE").

"it ROCKS! It's simple, small, and interfaces to Cartes du Ciel. What more can you ask for?"
- Astronomy author Rod Mollise. Read his review of RTGUI (Acrobat PDF reader is required).

Copyright (c) 2003-2015 by Robert Sheaffer

Free Windows Program - Controls Most "Goto" Telescopes
Press a button for "Goto", or for an 'Instant Skychart' of the selected object!

  • A Real-Time program, tells what's visible instantly, using GUI interface or keyboard. No need to prepare observations in advance. Find deep-sky objects, double stars, or other objects by their catalog or common names. Unusually rich search capabilities - each entry has up to five different names (Example: M1, NGC 1952, CrabNebula, Taurus, Planetary)
  • Create a custom "tour" based on your own criteria (by constellation and/or object type, elevation, magnitude) using the Search Wizard, or let RTGUI+S suggest the "Best" objects to observe, based on your location, telescope, sky conditions, and the time. Save these objects to a file, or print them as a list.
  • Fully-revised NGC/IC data (not available elsewhere) eliminating nonexistent or duplicate objects, "unknown" object types and most missing magnitudes. Over 2,500 double stars in default catalog, searchable by constellation.
  • Small and fast - Downloaded self-extracting file is only about 680k. 
  • Controls most Celestron and Meade "Goto" telescopes to slew directly to the selected object!
  • Using the Skycharts program (Cartes du Ciel) Version 3.2 or later, get an "instant sky chart" of the selected object. Skychart Ver 3.4 cannot be used with RTGUI. You can use ver 3.2x, 3.3x, and 3.5x, and later versions.)

    Read hand-held GPS Devices or Celestron and Meade GPS Telescopes to set highly-accurate Location and System Time. Read object position from most Celestron and Meade Goto scopes. Upload data from GPS devices to Meade Goto scopes.

    Locate Sun,Moon, and Planets, with excellent accuracy. Download Comet and Asteroid positions via the internet, for easy Goto, Skycharts, etc.

    Can set the "night vision" color palette in Windows.

    Displays Altitude and Azimuth of Astronomical Objects, updated in Real-Time, along with Rise, Set, and Transit times.

  • Automatically record object, time, & location information when the Observing Log is opened
  • Auxiliary Catalogs allow you to instantly locate hundreds of thousands of objects, using standard astronomical nomenclature, a time-saving tool for observing projects and for research.
  • Command-Line Parameters allow Scripting for automated operation
  • Click to Download Download Self-Extracting Archive Program for RTGUI+S, Version 10 (download size is under 700k). If updating to this new version of RTGUI+S from an older one, it is not necessary to unpack the new home location file RTGUI.HOM, saving you the trouble of re-entering your latitude, longitude, and telescope data.

    Click to Download     Download RTGUI, Version 10 as a ZIP archive.  

     (Windows Defender or your Browser may warn that the downloaded RTGUI file might be “dangerous,” simply because they do not know what it is. Just ignore this warning, and install it anyway. If you have any concerns, you can download RTGUI Ver. 10 as a ZIP file, and virus check the archive. Over 35,000 people have visited this page since 2005, and no security issues have ever arisen.)

    Read the FAQ - or - Read the program documentation

    RTGUI works well with Mike Swanson's Nexstar Control Pad Mike Swanson's Nexstar Control Pad

    Auxiliary Catalogs:(unzip catalogs into rtgui directory)

  • Download Messier Marathon Catalog (3k download, 11k unzipped. 110 entries). Once a year, in mid to late March, is it possible for mid-northern observers to see all 110 Messier objects in a single night's marathon observing session. This catalog contains all of the Messier objects, in the order that you need to observe them (whatever sets the soonest is "next"!). There is also a separate catalog for southern observers, with the visible M-objects ordered for their search. Just search for "M", and keep hitting "next"! (It's probably also a good idea to print out the list, for your location & time.)
  • Download Washington Double Star Catalog 1.8 Meg Download, 8.4 Meg unzipped. Revised Jan. 31, 2006 for compatibility with new Search Wizard. Includes constellation names for every object. Complete WDS 2001 catalog, 84,468 entries. Contains virtually every visual double star known. Don't waste those moonlit nights - observe thousands of double stars! In addition to the Constellation Names, I have cross-indexed the WDS with the HR and PPM catalogs, picking up Bayer (Gam Vir) and Flamsteed (61 Cyg) designations, as well as SAO numbers, where available. (Entries in the original WDS catalog contain only the WDS designation, and the DM numbers, so it's hardly user-friendly.) Separation and magnitude of companion are given, where available. I know of no other catalog of double stars so complete yet easy to search. For more information about this catalog, see http://ad.usno.navy.mil/wds.

  • Download PPM.ZIP Positions and Proper Motions Star Catalog in .RTG format ( 9.4 Meg download, 46.7 Meg unzipped. 468,861 entries). Contains all SAO catalog objects, also has PPM numbers, & HD numbers, now cross-referenced with data in the Bright Star catalog. Every entry now has a constellation name. ( For information on the PPM, see http://heasarc.gsfc.nasa.gov/W3Browse/star-catalog/ppm.html ). Catalog is in reverse order, starting with north polar objects and moving southward. This also places the smaller SAO and PPM numbers at the start rather than the end.
  • Other auxiliary catalogs can be found in the Files section of the RTGUI Yahoo group
    (You must join the Group for access to files)
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