Features of "The Digital Universe"

• The following databases are integrated into the software:
  1. Yale Bright Star (YBS) Catalogue of 9110 stars.
  2. Smithsonian Astrophysical Observatory (SAO) Catalogue of over 250,000 stars.
  3. Messier's Catalogue of 110 deep sky objects (galaxies, nebulae, and clusters).
  4. Sky & Telescope's NGC 2000.0 Catalogue of 13,226 deep sky objects.
  5. Tom Lorenzin's "1000+" database of observing comments for over 2000 objects.
  6. Jost Jahn's comet database containing 2298 cometary orbits.
  7. Jost Jahn's minor planet database containing orbital information for thousands of asteroids.
  8. Ted Molczan's and T. S. Kelso's orbital information for approximately 900 Earth-orbiting satellites.
• The software can generate accurate views of the night sky for any date from 100,000 BC to 100,000 AD.
• The package includes over 700 pages of hypertext, including an introduction to astronomy, dictionary of terms, biographies of famous people, celestial object descriptions, and summaries of every interplanetary spacecraft launched to date.
• More than 250 pictures are linked into the hypertext encyclopedia. They include images of all the planets, most of their satellites, all of the Messier objects, some NGC objects, and many miscellaneous images. A few audio clips are incorporated as well.
• A context-sensitive help system, linked into the online encyclopedia, is integrated into the software.
• The user can select whether or not they want to consider effects such as precession, proper motion, nutation, aberration, or refraction.
• The Digital Universe uses the latest analytic theories of motion for the planets (VSOP87) and their satellites, resulting in typical accuracies of better than 1 arcsecond (1/3600th of a degree).
• The current analytic theory of motion for the moon (ELP2000-85) has been extended to improve its accuracy even further for times within a few hundred years of the present. The extension was done specifically for The Digital Universe.
• NORAD's SGP4 model of orbital motion is used to accurately predict the apparent positions and movement of Earth-orbiting satellites. The Digital Universe can work with standard "2-line" orbit files. Hundreds of satellites are included with the software, and information is provided to explain how to obtain future data sets as new satellites are launched and older orbits decay.
• Unlike many other astronomy programs which only consider the four brightest satellites of Jupiter, The Digital Universe accurately computes orbits for the moons of:

  Earth:

  Our Moon

  Mars:

  Phobos and Deimos

  Jupiter:

  Io, Europa, Ganymede, Callisto, Amalthea, and Thebe

  Saturn:

  Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, Iapetus, Phoebe, Telesto, Calypso, and Helene

  Uranus:

  Miranda, Ariel, Umbriel, Titania, and Oberon

  Neptune:

  Triton and Nereid

  Pluto:

  Charon

  When the software is zoomed in sufficiently to the planet of interest, the moons are rendered in their proper positions.
• When zoomed in to most planets and satellites, the object's orientation and phase is determined and a latitude/longitude grid superimposed if the user desires. Maps of Venus, the Moon, Mars, Jupiter, and Saturn are incorporated into the software to generate accurate renditions of the appearance of these objects. The ring systems of Saturn and Uranus are rendered.
• Supports the Amiga preferences printer. Plots of star charts, etc. are far more than a simple screen dump. The maximum resolution of the printer is used for outstanding clarity.
• The user can enter his or her own horizon, if desired. Horizons for multiple observing sites can be configured.
• The user can select their location from a list of over 1000 cities, or enter their latitude, longitude, and altitude above sea level manually if higher accuracy is desired.
• Completely configurable IFF animations can be generated. To mention just two examples from the infinite number of possibilities, you can see how stars move and constellations distort over centuries, or view how Saturn's rings change their orientation and appearance over time. The Digital Universe can also save screen snapshots as ILBMs.
• A report generation feature lets you choose between a wide variety of data and customize tabular reports. They may either be printed or saved to disk.
• Provided that you have sufficient chip memory, the screen upon which The Digital Universe runs can be of any size. If the screen is larger that can fit on the monitor, you can scroll around simply by moving your mouse to the edge of the visible area. A screenmode requester is provided to allow users to specify their particular monitor.
• All development was done entirely on Amiga. It is not a port from the IBM or Macintosh world. As a result, the software closely adheres to the Amiga style guidelines and behaves in the manner you would expect from Amiga software.