Built for iOS

Stop guessing which
night is actually clear

Ostara is an app that gives astrophotographers real forecast judgment — 12 saved sites, 4 weather models, and a moon engine that tells you when it is worth the drive.

⚡ Get the app 📖 See a sample night
$ostara plan --site cabaneros --nights 10
12
Saved sites
4
Weather models
10
Nights ahead
0
Wasted drives this month (well, almost)
The problem

Clear is not the same as dark

Every weather app answers a question you did not ask. Ostara answers the one that decides the night.

🤖 A weather app

  • Cloud cover for the whole day, not the dark hours
  • No idea the moon is up until 04:12
  • Nothing about the ridge that blocks your target
  • One number for a 40km area
  • No opinion on whether to go

🎨 With Ostara

  • 12 sites, each with its own horizon and drive time
  • 4 models, cross-checked hour by hour
  • Moon, twilight and target altitude in one window
  • Works offline once the night is cached
  • One number: usable hours of astronomical dark
Coverage

12 saved sites

From the gate at Cabañeros to the ridge at Yeste — each site carries its own sky and its own drive.

📐Layout
🔤Typography
🎨Color theory
🌗Theming
🎬Motion
📊Dashboards
📋Tables
🧭Navigation
🪟Modals
🧾Forms
♿Accessibility
📱Responsive
🧩Design systems
✨Onboarding
🖼️Empty states
⚠️Error states
🪄Polish & detail
+ 14 more
Guardrails

18 checks before it says go

A sample of what gets checked before the app tells you to load the car.

01 Astronomical dark has to last at least 90 minutes after the moon sets Moon
07 Cloud cover under 20% for the dark window, not the whole day Cloud
14 Target has to clear the horizon mask you drew for that site Horizon
19 Seeing under 2 arcseconds, from the jet stream forecast Seeing
26 Drive plus setup has to fit before dark, not after it Timing
33 If two models disagree, it says so instead of averaging them Honesty
Automated

Told before you drive, not after

The Ostara engine re-reads every model each hour and scores the next ten nights against your own bar — before you spend two hours driving to a site under cloud.

  • One notification, with the time to leave
  • Names the check that failed and by how much
  • Cancels itself if the model turns
  • Scores every night out of 100
$ ostara check --tonight
 
Reading 4 models... done
⚠ Check 01 moon up until 04:12
⚠ Check 04 cloud 38% after 01:00
✕ Check 11 target behind the ridge
 
Night score: 62/100
✕ Not worth the drive — wait for Tuesday
Compatibility

Works where you already shoot

✅ iOS 🔧 Apple Watch 📦 Home screen widget 🧠 Siri shortcuts 🌗 Red-light mode

Give your nights a plan

One download. Every night afterward has 4 models and 18 checks deciding whether you load the car.

$ostara plan --site cabaneros --nights 10
See a sample night →