The settings in this view control the display of planets, moons, and other "minor bodies" in the solar system (asteroids and comets), as well as artificial Earth-orbiting satellites.
Planet & Moon Display
Show Planets: Displays planets and moons in the sky chart. When turned off, most of the other settings in this section are disabled.
with Grids: Shows planets and moons with surface coordinate grids. Planet grids show the orientation of the planet's equator and rotational axis. The equator and prime meridian are drawn as bold lines; other longitudes/latitudes are shown with lighter lines.
with Axes: Shows the rotational axes of planets and moons. Their north poles are drawn as bold lines; south poles are shown with lighter lines. Note: this option is only available in SkySafari Plus and Pro.
with Phases: Shows planets and moons with their night sides shaded in a darker color. When turned off, planets shown as fully illuminated, without any night side shading.
with Atmospheres: Shows the atmospheres of Venus, Earth, and Titan. To see these objects' surfaces unobscured by clouds, turn off this option. Note: this option is only available in SkySafari Plus and Pro.
with Surfaces: Shows planet and moons with realistic surfaces (and ring systems) using NASA planetary mission image data. This option can slow performance when zoomed in a planet's disk, but generates a very pretty view.
with Surface Labels: Shows labels for named planetary surface features like craters, mountains, maria, and canyons. Spacecraft that have landed on other solar system objects, and cities on Earth, are indicated with a green dot and label. Only the largest features are labelled when a planet's disk appears very small; to see more labels for smaller features, zoom in on the planet. Note: this option is only available in SkySafari Plus and Pro.
with Names: Shows names next to planets and moons.
with Minor Moons: Shows the "irregular" satellites of the outer planets, as well as other minor moons discovered by spacecraft exploration. All of these are small, asteroid-sized objects that are only visible in large professional telescopes. Many of these objects have highly inclined, elliptical, and/or retrograde orbits; most are suspected to be captured into temporary orbits around their primary planets. Note: this option is only available in SkySafari Pro.
Minor Body Display
Show Asteroids: Sets whether asteroids are displayed in the sky chart.
Show Comets: Sets whether comets are displayed in the sky chart.
Show Satellites: Sets whether satellites are displayed in the sky chart.
with Names: Sets whether the sky chart displays names next to asteroids, comets, and satellites.
Orbits, Paths & Shadows
Note: this section is only available in SkySafari Plus and Pro.
Show Planet Orbits: Shows orbital paths of the major planets around the Sun. Since the planets orbit in the nearly the same plane as the Earth (the Ecliptic plane), their orbits appear near the Ecliptic line - the Earth's orbit as seen from the Earth - in the sky. Note: this option is only available in SkySafari Plus and Pro.
Show Moon Orbits: Shows orbital paths of the moons around their primary (parent) planet. You may need to zoom in on a planet to see its moon orbits; Mercury and Venus have no moons!
Selected Object Orbit: Shows the orbit of the selected planet, moon, asteroid, comet, or satellite. You need to select such an object and turn on this option to show its orbit.
Selected Object Path: Shows the apparent path of a solar system object across the sky, with its position at specific dates labelled. The solar system object must be selected, and you must be viewing it from the Earth's surface, in order to see the path.
Earth & Moon Shadow Circles: Shows the Earth's shadow (when viewing from Earth) or the Moon's shadow (when viewing from the Moon). When this option is turned on, the Earth's (or Moon's) umbral and penumbral shadows are shows as concentric circles. Inside the smaller umbral shadow, the Sun is totally hidden; inside the larger penumbral shadow, the Sun is only partially blocked. This can be helpful for simulating lunar and solar eclipses, and illustrating the difference between total and partial eclipses.
Brightness & Size
Please Note: this section is only available in SkySafari Plus and Pro.
Magnitude Limit: This item lets you set the faintest planets, moons, asteroids, comets, and spacecraft that the sky chart will display. You can use this item to filter out the many hundreds of faint asteroids and comets that are not observable in backyard telescopes - or you may want to show them all!
Planet Magnification: This slider lets you magnify the Solar System's major planets by a factor of up to 10,000x their true size. The planets are very small compared to the space between them. This option is useful for showing comparative views of the planets from different perspectives.
Moon Magnification: This slider lets you magnify the moons of the planets by a factor of up to 100x over their true size. Since most moons are very small compared to their primary planet, this option lets you exaggerate them to make easier comparative views.
Update Minor Body Orbit Data
SkySafari normally updates its database of asteroid, comet, and satellite orbits once per week. In SkySafari Plus and Pro, you can tap this button to download new asteroid, comet, and satellite orbit data any time your iOS or Android device is connected to the internet. SkySafari will download the following files:
- Bright Asteroids - from the Minor Planet Center
- Observable Comets - from the Minor Planet Center
- Visual Satellites - from Celestrak.com
These downloads should take 10 - 30 seconds if you are connected to the internet by Wi-Fi, and a 1 - 3 minutes if you are connected by a cellular data network. If successful, SkySafari will report the number of asteroid, comet, and satellite orbits that it has updated. If that number is zero, it probably means SkySafari can't connect to the on-line data sources for this information (because the server is down, or because you are not connected to the internet, etc).
Updating your orbit data every month or so is a good idea. It will ensure that SkySafari's position predictions are accurate. This is especially true for satellites, whose orbits change rapidly due to atmospheric drag, and due to perturbations from the Earth's non-spherical gravity field.
Updating also ensures that as new objects are launched - or discovered! - SkySafari will be able to show them to you.
Please Note: this feature is only available in SkySafari Plus and Pro.