Messier: Greenberg Companion

110 deep sky objects, offline

Only for iPhone

Free · Designed for iPhone. Not verified for macOS.

iPhone

Every object Charles Messier cataloged, photographed from a backyard observatory in California. No account, no ads, and no internet connection needed. Every one of the 110 objects in Charles Messier's catalog, photographed from a backyard observatory in San Jose, California. In the 1770s Charles Messier was hunting comets. He kept a running list of the fuzzy objects that turned out not to be comets, so that he would stop wasting nights on them, he cataloged them. That list of annoyances became the finest catalog of galaxies, nebulae and star clusters visible from the northern hemisphere, and amateur astronomers have been working through it ever since. This app pairs every object with an original photograph, along with what it is, where it sits, how far away it is, and in most cases Messier's own words from the night he logged it. WHAT IS INSIDE - All 110 Messier objects, each with an original astrophotograph - Object type, constellation and distance for every entry - Messier's original observing notes, translated, for 104 objects - Filter by type to find galaxies, globular clusters, nebulae and more - A direct link to NASA's Hubble page for each object - Pinch to zoom on every image BUILT TO WORK ANYWHERE Everything lives on your device. No account, no sign-in, no ads, and no internet connection required. Take it to a dark sky site with no signal and it works exactly as it does at home. NO DATA COLLECTION The app collects nothing about you. No analytics, no tracking, no advertising identifiers. ABOUT THE PHOTOGRAPHS Every image was captured and processed by Chanan Greenberg at Greenhawk Observatory in San Jose, California, under ordinary suburban skies. Nothing here is borrowed from a professional facility or a survey archive.

Ratings & Reviews

  • 5.0
    out of 5
    1 Ratings

The developer, Chanan Greenberg, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    • Chanan Greenberg
    Size
    • 95.4 MB
    Category
    • Reference
    Compatibility
    Requires iOS 15.0 or later.
    • iPhone
      Requires iOS 15.0 or later.
    • iPod touch
      Requires iOS 15.0 or later.
    • Mac
      Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    • English
    Age Rating
    4+
    Copyright
    • © 2026 Chanan Greenberg
  • Developer Website
  • Privacy Policy