Night Sky Tools

Best free astronomy app to view sky map and stars. Your free telescope for space

Night Sky Tools is the ultimate collection of astronomical tools perfect for anyone interested in astronomy.

The calculations are of a high enough accuracy for almost all amateur astronomy applications.

Due to the fact that astronomy is often best when far from civilization where mobile signal may not always be reliable. Therefore, this app is (almost) completely self-contained and does not require any internet connection for most of the information available. The only exceptions to this are the SOHO solar images and NGC/IC, Messier, Caldwell and Binary star images and weather forecast which are loaded dynamically, as well as the refreshing of satellite, comet and near-earth asteroid data.

Night mode turns the display red for night observations without having to ruin your night vision.

The Sky Map makes use of the direction sensors of the device to show the sky above (or below you). Most of the features can be toggled in the settings. The Sky Map also allows you to turn on the device's camera to see the view behind the device with the sky map superimposed over it.

The direction sensors of the device may need to be calibrated if the map appears to be pointing in the wrong direction. To calibrate the device's sensors wave the device in a figure-8 pattern. If the direction is still off, then the direction calibration can be adjusted manually by changing the setting in the Settings screen.

The observation log, allows you to save observations in the applications, as well as manage a list of astronomical equipment and observing locations. This equipment is also available for use in the Telescope Calculator.

Most of the data screens have an option to share the data via email, or other similar apps able to accept HTML content.

The Astronomical Time is also available as a Home screen widget. To use the widget, the app needs to be installed onto the internal storage instead of the SD card, otherwise it will not be available.

Some permissions are required for correct functioning of the app:

Location - used to determine user location throughout the app

Camera/Microphone - used to allow camera background in skymap. The microphone is never used but this permission is bundled with camera.

Photos/Media/Files - used to allow proper functioning of the full screen images and caching of images

Network access - used to do online searches, and downloading comet, asteroid and satellite data, object images and geocoding.

The app is jam-packed with features:

- Observe the sky with the skymap, planisphere, aurora forecast, polar finder, weather forecast, daylight map, Moon and Mars maps, SOHO images, Jupiter and Saturn's moons, Moon and Sun calendars and what's up.

- Detailed object information on the planets, constellations, comets, exoplanets, meteor showers, near-earth asteroids, satellites, as well as the full NGCIC, Caldwell, Messier, 6th catalog of Visual Binary Stars by the USNO and General Catalog of Variable Stars catalogs, as well as a SIMBAD search.

- Calculate angular separation, atmospheric refraction, magnitude, coordinate conversions, visual limiting magnitude, precession, redshift, and telescope airy disc, f-ratio and magnification

- Astronomical references, glossary, HR diagram and stellar classification.

- Astrophotography tools for exposure time, CCD resolution, Untracked exposure time and optimal f-ratio.

- Emphemerides for eclipses, equinoxes, conjunctions and oppositions, the sun, moon and planets

- Observation log

- Astronomical time