SkySafari needs to know your location on Earth in order to correctly plot the location of objects in the sky. You can set this in the Location view from the main Settings screen. Four pieces of information are necessary:
Latitude - distance north or south of the equator
Longitude - distance east or west of the prime meridian
Elevation - altitude above sea level
Time Zone - local time offset in hours from Universal Time (UT), previously called Greenwich Mean Time (GMT)
A time zone west of (behind) Universal Time is negative; time zones east (ahead) of UT are positive. Always enter the time zone offset for Standard Time only. Don't enter a Daylight Saving Time offset here. SkySafari will automatically correct for Daylight Saving Time. See the Date & Time Settings Help.
Please note: in SkySafari Plus and Pro, you cannot change your location settings while you are orbiting another object in the solar system. These settings only refer to your location on Earth. To change them, you first need to return home to Earth. See the Orbit button Help for more information.
Use Current Location
Tap the "Use Current Location" button to automatically determine your location from your iPhone's Location Manager, your Android device's GPS, or other information supplied by your internet service. When the location information is obtained this way, your location name is automatically filled in as "Current Location".
Choose Location From Map
If your mobile device is connected to the internet, you can use Apple or Google maps to choose a new location. This is useful if you want to see the sky from a place other than where you are located right now. You could use this feature to view the sky as it will appear from a distant city or island where you're planning to take a vacation.
After you tap this option, a map view will appear, centered on your current location. You can pinch or swipe this map to zoom or move around, just as you would with the built-in Maps app on your device.
Tap and hold to drop a pin on your desired location. Then tap Done at the top of the screen. SkySafari will use the longitude, latitude, and location name where your pin dropped. SkySafari will make a best guess about the elevation and time zone, since this information is not available from Apple or Google Maps.
Choose Location From List
If your mobile device is not connected to the internet, and GPS or Wi-Fi-based location services are not available, you can choose a location from a searchable list of thousands of cities in SkySafari's database.
Tap "Choose from List" to see a list of locations, sorted by country. Choose a country to see a list of cities in that country. Choosing a city will automatically fill in the data for you. You can also search for any location in SkySafari's database by entering its name in the search field above the list of countries. If SkySafari finds more than one location which matches the name you entered, it will list all matching locations, and you can choose the one you want. If there is only one matching location, SkySafari will use it.
The location database in SkySafari's basic version includes every city worldwide with more than 100,000 inhabitants - a total of over 4,000 cities. In SkySafari Plus and Pro, the location database includes all cities with more than 10,000 people, plus more than 500 observatories, star parties, NASA centers, and other "astronomical" locations - a grand total of over 30,000 locations in all!
Save User-Defined Location
Tap the "Save User-Defined Location" to store a manually-entered location for retrieval later. To retrieve a user-defined location, tap the "Choose Location from List" button, then choose the "User-Defined Locations" group. You must name your location something other than "Current Location" before saving it as user-defined. If you choose the same name as an existing user-defined location, that existing location will be overwritten with the new longitude, latitude, etc. currently displayed in the Location view.
You can delete user-defined locations as follows:
Tap the "Choose Location from List" button. Choose the "User Defined Locations" group at the end of the location groups list.
Tap the "Edit" button at the top of the user-defined locations list.
Tap the small, red, round, "-" button for each user-defined location you wish to delete. Confirm by tapping the red "Delete" button that appears to the right.
When you are finished, tap the "Done" button at the top of the user-defined locations list.
Please Note: the User-Defined Location feature only available in SkySafari Plus and Pro.