Mobile Observatory

Astronomy at your Fingertips

The best Astronomy App for Android

Accurate Sky Simulation

Mobile Observatory shows you a realistic view of the sky for any time and any place on Earth. It provides the most accurate simulation of sky colors available for any astronomical app. Twilight looks gorgeous, the landscape is illuminated by the full moon, and the sky at blue hour looks just like the real thing.

LARGE ASTRONOMICAL DATABASE

The database includes more than 2.5 Mio. stars, >2500 deep sky objects (galaxies, nebulae, clusters, ...), 60 000 minor planets, about 1000 comets, more than 5000 artificial satellites (ISS, Starlink, ...), and all prominent meteor showers. All data are kept up-to-date by free daily updates.

Celestial Events

One of the biggest strengths of Mobile Observatory is its user-friendly celestial events section. You will never miss a lunar eclipse, a bright ISS pass, or a nice conjunction between Jupiter and Saturn. Daily automatically generated reports of celestial events for your location keep you up-to-date.

Key Features of the PRO version

General

Photo-realistic display of the night and day sky with correctly illuminated landscape
Positions of all included objects computed with scientifically professional accuracy
Augumented sky view using your device's camera
3D-view of the Solar System
Cardboard VR viewing of the night sky or the Solar System in 3D
Daily notifications of current celestial events
Lots of great widgets for your home screen

Database

45 000 stars plus optionally 2.5 mio stars for download (to magnitude 13)
Artificial Satellites including the International Space Station (ISS) and all Starlink satellites
2 500 selected NGC objects (galaxies, clusters, ...)
Messier Catalog (110 objects) complete with images
Caldwell Catalog (110 objects) complete with images
Hidden Treasures Catalog (109 objects) complete with images - Meteor streams (begin, maximum, hourly rate, ...)
More than 60 000 Minor Planets with daily updates of orbital parameters
More than 1 000 Comets with daily updates
All bright Artificial Satellites including the International Space Station (ISS) and all Starlink satellites
All major Meteor streams (begin, maximum, hourly rate, ...)

Additional features

Live mode (point device on sky and get information on what you see)
Automatically generated visibility report for any object
Fully customizable main menu
Current images of the Sun and sunspot number
Lunar and solar eclipses information
Twilight times, length of day, blue and golden hour
Rise, set, and transit times for any object
Lunar librations, ascending node, maximum declination
Simulation of light pollution
Dates of conjunctions between any object with planets or the Moon
Accurate calculations for dates between 1900 and 2100

What the users say

A must-have for amateur and professional astronomers alike. This app is well-designed, making it easy to get to whatever data source you require, such as knowing when is the best time to view the moon or planets. Tons of knowledge is available in just a few clicks, something I greatly appreciate. Highly recommended!

Trevor Williams

June 2020

It's the only astronomy app I use on an almost daily basis and has served me very well over the years.This new version has some nice new features, but the biggest and best improvement for me is the graphic depiction of the night sky - especially during twilight. If I had to choose just one app to recommend someone - paid or free - I would recommend MO.

Richard Bartlett

February 2019

Great app, almost overwhelming in scope. However thanks to this app, I had no trouble finding the currently very visible comet C/2020 F3 (NEOWISE) and it also told me what the best time was at my location to look for it. This was awesome!

Gerald Mengisen

July 2020

I have a library of astronomy apps. Each does a few things well but I was always looking for something that did more. This is the one. The content is fantastic, the UI is spot on. Kudos dev for this amazing app. Best $7.50 I"ve ever spent. Thank you.

Silvana Della Camera

June 2020

News

Mobile Observatory 4.0.0 represents a complete overhaul of the app with modern architecture and technologies. Due to Google Play Store requirements, significant technical changes were necessary. Please note that not all features from version 3.x have been migrated yet, but they will be added back in upcoming updates.

New in Version 4.0.0 (October 2025):

Important Note: Version 4.0.0 is a major architectural rebuild. Some features from version 3.x are temporarily unavailable as they are being migrated to the new modern architecture. These features will be progressively added back in upcoming updates. Thank you for your patience and understanding!!