A planetarium in your pocket: how does the Sky Map app work

Visiting a planetarium is a unique experience that allows you to observe and admire the sky like never before. However, those who don't know much about astronomy are likely to be left with several more questions than answers after such a visit. At the end of the day, you have to have a certain notion to discover those stars that everyone is talking about.

For this reason, installing Sky Map on your mobile phone can be a good alternative. This free download application allows you to turn any Android phone into a small pocket planetarium.

Thanks to its map of the night sky, this app makes it easier to identify stars, planets and nebulae. If you prefer to have a somewhat clearer view, you can deselect different categories of celestial bodies on the left edge of the screen to hide them.

You can also do a full-text search, for example, and enter directly the name of a planet, star or constellation. Next, you have to move your smartphone across the night sky. A search circle with indicator arrow on the screen aids in the process and points in the right direction until the corresponding object is found.

The map can be zoomed in and moved automatically as the user scrolls or moves the phone. To do this, the app accesses the phone's location. If these are disconnected, the application does not work.

However, the map can also be moved manually using an adjustment on the right edge of the screen. This is also useful if you want to explore areas of the night sky far from your location.

As for the location, the application obtains it from GPS data. You can also enter it manually, by longitude and latitude, or simply by adding the name of the place.

The application was originally developed by a Google project team in cooperation with Carnegie Mellon University. Since 2012, Sky Map is an open source project whose maintenance depends on volunteers.

dpa