What’s new

CyberSky 4 introduces many new features, major improvements, and minor enhancements requested by users. Most of these changes are briefly described below.

Saving and printing maps

  • Save maps as ‘CyberSky Map’ files
    You can save maps as ‘CyberSky Map’ files and open them again later, just like saving and opening documents in a word processor. CyberSky includes many sample maps that show interesting astronomical events and show off the program’s features. The Map Description command on the Map menu allows you to type a description of a map and any notes you think are important. This description is saved when you save the map and is automatically displayed when you open the map later.
  • Save map images in more formats
    You can save maps as GIF, JPEG, PNG, and TIFF images as well as Windows bitmap images.
  • Improved printed maps
    Maps printed by CyberSky are more attractive and can be customized in more ways. You can choose whether or not to include legend and information boxes on printed maps. You can customize border and background colors, as well as the colors and fonts used for titles, heading, and other text.
  • Copy maps and paste them into other programs
    The Copy command on the Map menu lets you copy maps to the Clipboard and then paste them into other programs.

Map features

  • Drag the map to look around
    Looking around the sky is easier than ever. You can now click the map and drag it in any direction to see other parts of the sky.
  • Field of view replaces zoom level
    You can enter the map’s field of view directly. CyberSky no longer uses zoom levels.
  • Customizable zoom speed
    You can change the factor by which the field of view is decreased or increased when you zoom in or out. This allows you to control how many steps it takes to zoom in or out a certain amount.
  • Single magnitude limit
    There is one magnitude limit for all objects rather than separate limits for stars and deep-sky objects. When you zoom in and out, the magnitude limit is no longer increased and decreased in half-magnitude steps, but is calculated directly from the map’s field of view.
  • Legend
    The Legend window displays a key to the symbols used to represent different types of objects, the magnitudes of stars, and the spectral types of stars on the map.
  • Flip the map horizontally or vertically
    You can flip the map horizontally, vertically, or in both directions so that it matches what you see through a telescope.
  • Atmospheric refraction control
    You can use the Atmospheric Refraction command on the Map menu to turn the adjustment for atmospheric refraction on and off. This adjustment no longer depends on the display of the horizon.
  • Improved variations in sky color
    The color of the sky varies not only with the visibility of the Sun, but also with the visibility and phase of the Moon. The sky color changes smoothly from the daytime color to the nighttime color during twilight, rather than in three steps corresponding to civil, nautical, and astronomical twilight. The sky color changes during solar eclipses as well.
  • Filled horizon
    The area under the horizon is filled with its own color rather than appearing in the same color as the sky. This feature is especially useful when you’re looking at a small section of the sky, because the background color alone tells you if you’re looking below the horizon.
  • Map information
    The Map Information dialog box displays the viewing location and time, the map’s field of view and magnitude limit, and the coordinates of the center of the map. It also displays the value of delta-T that CyberSky is using. This value may be useful to you if you’re interested in ancient eclipses. The dialog box’s Copy button allows you to copy and paste this information into another program.
  • ToolTips for objects on the map
    You can quickly identify an object you see on the map and view basic information about it by resting the pointer over the object. After about a second, the information is displayed in a small ToolTip window that appears near the pointer.

Centering and locking objects

  • Improved search dialog boxes
    The lists of objects in search dialog boxes include information you may find helpful in selecting an object, such as the constellation an object is in or its magnitude. Search dialog boxes have both Center and Lock buttons, so you can choose whether you want to lock an object or only center it. Search dialog boxes also have Properties buttons that allow you to display information about objects. This feature lets you display information about objects even if they don’t appear on the map.
  • Search for stars by Bayer letter and Flamsteed number
    The Star Search dialog box allows you to search for stars by Bayer letter and Flamsteed number.
  • Search for ecliptic and galactic coordinates
    You can search for points in the ecliptic and galactic coordinate systems.
  • Improved marker for centered objects
    The small cross that marks an object you centered no longer disappears when the map is redrawn. The marker remains visible and follows the object if it moves away from the center of the map. You can use the Mark Object command on the Search menu to turn the marker on and off.
  • Quickly center an object again
    If you center an object and then look at another part of the sky, you can use the Center Again command on the Search menu to quickly bring the object back into view.
  • Lock more types of objects
    Previously, you could lock the Sun, the Moon, or a planet to the center of the map so that it stays in view as it moves across the sky. You can now also lock a star, a deep-sky object, the Earth’s shadow, the antisolar point, an asteroid, a comet, or a meteor shower radiant.

Location, time, and animation

  • Updated database of locations
    Hundreds of locations have been added to the program’s database, bringing the total to 1,651 locations. Elevation data has been added for most locations in the database. All known errors in the location database have been corrected.
  • Quick access to the North Pole, equator, and South Pole
    Commands on the Location menu allow you to quickly set the viewing location to the North Pole, equator, and South Pole. This feature is very convenient when using CyberSky for educational purposes.
  • Weather conditions
    You can specify the temperature and pressure at the viewing location to increase the accuracy of atmospheric refraction calculations.
  • View the sky over a wider range of time
    You can view the sky at any moment from 15,000 BC to 15,000 AD. This greatly expanded range of time allows you to see one complete precession cycle and to explore possible astronomical alignments and events farther back in time. (The positions of the Sun, Moon, and planets are very accurate only between 3000 BC and 3000 AD. As you step farther and farther outside this range, their positions—especially those of the outer planets—become increasingly inaccurate.)
  • Improved time controls
    The toolbar buttons that moved the time forward or backward by a day or hour have been replaced by buttons that move the time forward or backward by a year, week, day, hour, minute, or second. These buttons are located in the Control bar, below the time display. The DST check box above the time display shows you whether CyberSky is adjusting for daylight-saving time, and allows you to quickly turn this adjustment on or off.
  • Specify that the computer’s clock is set to universal time
    Previous versions of CyberSky assumed that the computer’s clock is set to local time. This was inconvenient for users who prefer to keep their computer’s clock set to universal time (Greenwich mean time). You can now specify that the computer’s clock is set to universal time rather than local time.
  • Set the sidereal time
    You can enter a sidereal time to specify the viewing time.
  • Improved animation controls
    The animation time step is displayed in the Control bar. The toolbar buttons that controlled animation have been replaced by buttons in the Control bar below the time step display. The Play Forward and Play Backward commands both start and stop animation; the Stop command has been removed. You can now control the speed at which animation takes place.

Constellations and asterisms

  • Customizable constellation names
    Constellation names and the positions at which these names are drawn on the map are stored in the files ‘Names’ and ‘Coordinates’ found in the Data\Constellations folder. You can customize the names and label positions of constellations by editing these files.
  • Asterisms
    You can display asterisms—groups of stars such as the Big Dipper, the Sickle, and the False Cross, that aren’t among the 88 official constellations.
  • Customizable asterism names
    Asterism names and the positions at which these names are drawn on the map are stored in the files ‘Names’ and ‘Coordinates’ found in the Data\Asterisms folder. You can customize the names and label positions of asterisms by editing these files.

Stars, deep-sky objects, and the Milky Way

  • Updated star catalog with more stars
    CyberSky uses the SKYMAP SKY2000 Version 5 Master Star Catalog, produced by the Goddard Space Flight Center, Flight Dynamics Division, which increases both the quality and quantity of information about each star. The number of stars has been increased from 80,179 to 299,458. Note that the trial version of CyberSky only includes 15,565 stars.
  • More information about stars
    You can view more information about a star, including its SKYMAP catalog number, galactic coordinates, hour angle, B-V color index, Morgan-Keenan spectral type, one-dimensional spectral type, approximate surface temperature, parallax, distance, and proper motion.
  • Star bitmaps
    CyberSky displays stars using bitmaps. There are three sets of bitmaps for you to choose from: bitmaps with bold rainbow colors, bitmaps with subtle rainbow colors, and bitmaps that approximate the real colors of stars as seen from space. The program can still draw stars as filled circles, if you prefer.
  • More star names
    More star names have been added to CyberSky. The names of some navigational stars have been changed to the names used in nautical almanacs. Alnair is now Al Na’ir, Deneb Kaitos is now Diphda, Alnath is now Elnath, Rigelkent is now Rigil Kentaurus, and Alsuhail is now Suhail.
  • Customizable star names
    Star names are stored in the file ‘Names’ found in the Data\Stars folder. You can customize the names of stars by editing this file.
  • Display Bayer letters as names rather than symbols
    You can choose to have the Bayer letters of stars drawn as Greek letter names (Alpha, Beta, Gamma) rather than as symbols (α, β, γ) if you find the symbols confusing or hard to read.
  • Proper-motion vectors
    You can display proper-motion vectors, which are lines that show the speeds and directions that stars are moving. Stars that are close tend to have proper motions that are larger than stars that are far away, so looking for large proper-motion vectors is a way to find nearby stars. Proper-motion vectors can also help you see which stars are part of the same cluster and which ones just happen to lie in the same direction in space. Members of a cluster generally move in the same direction and at the same speed; stars that move in a different direction or at a different speed aren’t part of the cluster.
  • Updated deep-sky object catalog with more objects
    CyberSky uses version 7.7 of the Saguaro Astronomy Club’s database of deep-sky objects. The number of deep-sky objects has been increased from 479 to 2,200. Note that the trial version of CyberSky only includes 255 objects.
  • More information about deep-sky objects
    You can view more information about a deep-sky object, including its galactic coordinates, hour angle, angular size, position angle (if a galaxy), surface brightness (if a galaxy, globular cluster, planetary nebula, or supernova remnant), number of stars (if an open cluster), magnitude of the brightest star (if an open cluster), magnitude of the central star (if a planetary nebula), description, and additional notes.
  • Select which types of deep-sky objects are included on the map
    You can turn on or off different types of deep-sky objects independently of each other. You can, for example, display only galaxies.
  • Customizable deep-sky object names
    Deep-sky object names are stored in the file ‘Names’ found in the Data\Deep-Sky Objects folder. You can customize the names of deep-sky objects by editing this file.
  • Milky Way
    You can display the outlines of the Milky Way. You can choose to display up to five sets of outlines, each of which encloses regions of the Milky Way that have roughly the same level of brightness.

Planets, asteroids, and comets

  • Improved accuracy
    The calculated positions of the Sun, Moon, and planets are even more accurate. The positions of the Sun and planets match the Jet Propulsion Laboratory’s DE404 ephemeris to within a fraction of an arc second from 1350 BC to 3000 AD. For the outer planets, the agreement is still within about an arc second as far back as 3000 BC; the positions of the Sun and inner planets may be somewhat less accurate this far back in time, but they’re still accurate enough for archeoastronomy research. The results for the Moon match the DE404 ephemeris to within 0.5″ for all dates between 1369 BC and 3000 AD.
  • More information about planets
    You can view the hour angle of the Sun, the hour angle, elongation, phase angle, and age of the Moon, and the hour angle and phase angle of a planet.
  • Select which planets are included on the map
    You can turn on or off the Sun, Moon, and planets independently of each other. If you’re using animation to watch Mars undergo retrograde motion, you can turn off other planets so that you can concentrate on Mars. This feature also allows you to turn off the Sun and Moon so that you can see planets that are behind them.
  • Glow around the Sun
    CyberSky draws the glow we see around the Sun due to the haze in the Earth’s atmosphere. This feature makes the Sun stand out on the map.
  • Improved display of Jupiter’s moons
    Jupiter’s four brightest moons—Io, Europa, Ganymede, and Callisto—cast shadows on the planet’s disk. These moons are drawn in a darker color when they pass through Jupiter’s shadow.
  • Saturn’s moons
    You can see the positions of Saturn’s eight brightest moons—Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, and Iapetus.
  • Antisolar point
    You can display the position of the antisolar point, which is the point in the sky that’s directly opposite the Sun.
  • Lunar eclipses
    You can display the cross-section of the Earth’s shadow at the distance of the Moon, which lets you see the circumstances of lunar eclipses. When the Moon passes through the Earth’s shadow, a lunar eclipse takes place.
  • Asteroids and comets
    You can display the positions of asteroids and comets. You can center asteroids and comets, lock them to the center of the map, display their paths, and display detailed information about them. You can update the program’s asteroid and comet catalogs by downloading new files without charge from the Internet.
  • Meteor showers
    You can display the positions of meteor shower radiants, which are the points in the sky from which shower meteors appear to come. You can display all radiants or only those of showers that are currently active. You can center radiants, lock them to the center of the map, and display detailed information about meteor showers.
  • Paths with respect to the horizon
    Previously, CyberSky could only display the paths of Solar System objects with respect to the background stars. The program can now also display paths with respect to the horizon. This feature makes it possible to create maps that show the analemma, as well as maps that show the changing positions of Mercury or Venus in the morning or evening sky.
  • Overhead view of the Sun and planets
    The Solar System window shows the positions of the planets in their orbits around the Sun. Because this view appears in a separate window, you can watch the planets revolve around the Sun and see them move across the sky at the same time in the program’s main window.
  • Planet visibility graph
    The Planet Visibility dialog box displays a graph that shows when the Sun, Moon, and planets rise, transit, and set on a given day. This graphical display makes it easy to see which planets are above the horizon at the current time. You can view the rise, transit, and set times in numerical form in the Planet Events dialog box.

Coordinate-system lines, finder circles, and compass

  • Ecliptic and galactic coordinate-system grids
    You can display the ecliptic and galactic coordinate-system grids.
  • Improved display of grids, lines, and points
    You can choose whether or not grid lines are drawn through the coordinate-system poles. The ecliptic, celestial equator, and galactic equator are labeled. The equinoxes, solstices, and other important points are marked and labeled as well. A toolbar button lets you quickly turn labels on and off.
  • Finder circles
    You can display finder circles like those you see through a Telrad reflex sight or a similar sighting device. You can customize the diameters of these circles to match those seen through another sighting device, or to match the fields of view seen through your telescope with different eyepieces.
  • Compass
    You can display a compass to show the cardinal directions on the map. The compass can be drawn in the upper left, upper right, lower left, or lower right corner of the map, or at the map’s center.

Miscellaneous features

  • Night-vision mode
    When you turn on the program’s night-vision mode, the user interface and map are drawn in shades of red on a black background. Dim red light has the least effect on your ability to see faint objects. By using night-vision mode and reducing the brightness of your computer screen, if necessary, you can preserve the dark adaptation of your eyes while using the program outdoors. The colors used during night-vision mode can be customized, so you can choose other shades of red.
  • Quickly view rise, transit, and set events
    The rise, transit, and set times displayed in object information dialog boxes now have buttons labeled ---> next to them. When you click one of these buttons, the map’s time is set to the displayed time and the map is redrawn with the object at the center.
  • More options for labeling objects
    You can label each star with its distance, each deep-sky object with its magnitude, and each planet with its magnitude or distance. Each star label, deep-sky object label, and planet label can be drawn in the same color as the object it labels. You can specify magnitude limits for labels that differ from the map’s magnitude limit. For example, you can specify that only deep-sky objects of magnitude 8 or brighter should be labeled.
  • Improved measuring of angular separation
    You now measure the angular separation between two objects by right-clicking an object, clicking Measure, and then clicking another object. The angular separation appears in a dialog box rather than the status bar, along with the position angle and the difference in right ascension and declination between the two objects.
  • Customization of date and time formats, measurement system
    The date and time formats as well as the measurement system used by CyberSky are now independent of the Windows settings. This allows you to use the year/month/day and 24-hour clock formats that are commonly used in astronomy without changing the formats used by Windows. You can choose to use BC/AD or BCE/CE as the era abbreviations. You can choose to use the metric or U.S. measurement system.
  • New Help file
    The CyberSky Help file has been completely rewritten, and now uses Microsoft’s HTML Help format.