Essential for your researching toolbox!
I’ve been waiting for this exact tool for quite some time. Extremely well executed and makes calculations a breeze! Highly recommended!
$6.99
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About
Discover celestial alignments with this tool that uses your iPhone's GPS, compass, and camera to identify stars and planets rising and setting along any line. Explore historical and future celestial events from 5000 BC to 3000 AD, including lunar standstills.
✓Capture alignments with GPS, compass, and camera
✓Track 21 navigational stars and major planets
✓Calculate positions from 5000 BC to 3000 AD
✓Detect lunar standstill points
✓View sites on a satellite map
✓Save alignments to calendar
✓Export to Google Earth
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What's New in My Cosmic Compass
2.5
November 8, 2026
• Sites on a satellite map of the world, with region buttons to jump between continents • A workspace for every site: a compass ring with its lines, the Moon's standstill points and where each line's star rose in the year you choose. Move through time and watch the stars travel. Tap any mark for an explanation • Redesigned results: the answer in one sentence, the horizon drawn as a night sky, and details on request • How it was calculated: your line, the horizon, the declination and the target, step by step • Featured sites now state the alignment their builders intended, with the site's story • Stars placed where they are first seen, as the builders saw them • Dates in the calendar of the time: Julian before 1582, Gregorian after • More accurate planet and Moon positions • The Moon tonight at your location on the home screen • Star paths in the camera view, and compass calibration on the Moon • Export a single site with its lines to Google Earth as KML • Sort your sites by name or date • A visible progress line while planets are calculated • Designed for iPhone & iPhone Duo • Updated User Manual
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FAQ
What is My Cosmic Compass?
My Cosmic Compass is an iPhone tool that helps you discover which stars and planets rise and set along any alignment you point your device towards. It calculates these celestial positions for any year from 5000 BC to 3000 AD.
How does My Cosmic Compass work?
You point your iPhone along an alignment, like a monument's edge, and tap to capture. The app uses GPS, compass, and camera to record the bearing and then calculates the celestial bodies visible along that line at your chosen time.
Can My Cosmic Compass be used offline?
Yes, My Cosmic Compass works offline, allowing you to explore celestial alignments even without an internet connection. This makes it useful for fieldwork or remote locations.
What historical periods can My Cosmic Compass cover?
The app can calculate star and planet positions for any year between 5000 BC and 3000 AD. You can set the year a monument was built to see what the sky looked like then.
Does My Cosmic Compass account for precession?
Yes, My Cosmic Compass combines the Vondrák long-term precession model with proper motions from the Hipparcos catalogue to provide accurate historical star positions, accounting for the slow wobble of Earth's axis.
What is a lunar standstill, and does My Cosmic Compass detect it?
A lunar standstill occurs every 18.6 years when the Moon reaches its most extreme rising and setting points. My Cosmic Compass detects these standstill points around sites.
What devices does My Cosmic Compass support?
My Cosmic Compass is currently supported on iPhone devices. It was released on 2025-12-10 and last updated on 2026-11-08.
How much does My Cosmic Compass cost?
My Cosmic Compass is a paid application, available for $6.99. It does not feature in-app purchases or advertisements.
