Andromeda
M 31 · NGC 224
- Magnitude
- 3.4
- Constellation
- And
- Distance
- 0.78 Mpc
- Right asc.
- 00h 42m
- Declination
- +41° 16′
- Apparent size
- 178′ × 63′
Your observations
- Vercors dark site, 8" f/525 Oct 2025
- Back garden, 10 × 50 binoculars5 Nov 2024
- Record shown
- M 31NGC 224 · Andromeda
- Magnitude
- 3.4naked-eye visible
An observing log for amateur astronomers
Every night under the stars deserves better than a lost notebook.
You find the object, then jot down the date, the site, the eyepiece, how transparent the sky was. Six months later the note is illegible, or the notebook got soaked in dew. AstroCollect keeps the record: 395 documented objects, your photos attached to each one, your sessions timestamped, and nothing leaving your private iCloud.
7-day trial, then €2.99
One-time purchase · no in-app purchases
- Window computed
- 24 hlocal ephemerides
- Works offline
- 100 %except weather
Knowing whether it's worth setting up the telescope
The planner traces the object's path over the next 24 hours from your location, and tells you when it climbs above 30° — the altitude below which atmospheric turbulence ruins the view.
- EphemeridesRise, transit and set computed with Jean Meeus's algorithms, locally, with no network call.
- MoonPhase, illumination and angular distance to your target: a full Moon 15° from a magnitude 8 galaxy is a wasted evening.
- Cloud coverThrough WeatherKit when the network is there. Without it, the rest of the calculation still works.
- Light pollutionEstimated from your location, to decide between the back garden and an hour's drive.
- Unique objects
- 395one object = one record
- Catalogues
- 6cross-referenced
Six catalogues, cross-referenced
The Trifid Nebula is M 20 to Messier and NGC 6514 in the New General Catalogue. That isn't two objects: it's a single record, listed in both catalogues. Your photos and notes stay attached to the object, whichever name you reach it by.
| Catalogue | What it holds | Example | Objects |
|---|---|---|---|
| Solar SystemSun, Moon, planets | Positions computed in real time, not frozen coordinates. | Jupiter, mag −2.7 | 10 |
| MessierM 1 – M 110 | The 1781 classic. The target list for the spring Messier Marathon. | M 42, Orion, mag 4.0 | 110 |
| CaldwellC 1 – C 109 | Patrick Moore's complement, including the southern sky Messier ignored. | C 20, NGC 7000, mag 4.0 | 111 |
| NGCNew General Catalogue | A selection of the most reachable among the original 7,840 entries. | NGC 5194, Whirlpool, mag 8.4 | 283 |
| ICIndex Catalogue | The 1895 and 1908 additions to the NGC, mostly faint nebulae. | IC 2602, Southern Pleiades, mag 1.9 | 94 |
| Point objectsNotable stars | The landmarks you use to get oriented and align a finder scope. | Polaris, mag 1.98 | 6 |
| Total, cross-catalogue duplicates excluded | 395 | ||
- Screens
- 4one codebase
The same library, on whichever screen is to hand
The phone beside the telescope, the Mac when it's time to sort the photos, the Apple TV to share your images on the big screen.
- Purchase
- Universalonce, everywhere
One purchase, four devices
-
iPhone & iPad
iOS 17.0 or laterThe full app: capture, planning, sessions, statistics, exports.
Available -
Mac
macOS 14.0 or laterA native app that feels at home on the Mac: sidebar, multiple windows, drag photos in from the Finder.
v1.15 -
Apple TV
tvOS 17.0 or laterA read-only companion: your photos, catalogues, sessions and statistics on your TV.
v1.16 -
Android
No date announcedUnder consideration. The export format is already documented so a future app could read your data back.
Exploring
- Account needed
- Noneno email, no password
- Trackers
- 0no third-party SDK
Where you observe from isn't a product
An observing log is a record of where you go at night and what gear you own. None of that has any business leaving your devices.
- No server in between. Sync runs through CloudKit, inside your own iCloud account. The developer has no access to that database.
- GPS coordinates in your photos aren't read by default. You have to turn that on explicitly, object by object.
- No analytics SDK bundled. No Firebase, no Crashlytics, no audience measurement inside the app.
- Full export, whenever you want. A documented ZIP archive holding your photos and notes in the clear. Nothing is held hostage.