Astro-Photographer

Astro-Photographer answers one question: what is worth going out to photograph this month, from where I actually am?

It does not list every astronomical event. It computes each one from your coordinates and gives it a score out of 100 for how photographable it is from your sky: altitude above your horizon, moonlight that night, distance from twilight, the weather, and the darkness of your site. Then it ranks the opportunities by score, so the top of the list is what deserves the tripod and the cold night.

Everything is computed on your device with published astronomical algorithms (Jean Meeus; JPL orbital elements). No account, no ads, no tracking.

Try everything for 14 days, then one purchase unlocks it forever. No subscription, no renewal.

WHAT IT COMPUTES
• Moon phases to the minute, the new Moon that opens the deep-sky window, and the full Moon near the horizon.
• Planets: oppositions of Mars, Jupiter and Saturn, greatest elongations of Mercury and Venus, and close conjunctions with each other and the Moon.
• Solar and lunar eclipses computed for your location, not for "greatest eclipse": magnitude, type and contact times as you will see them.
• New crescent visibility for the Hijri month: when it can be seen from your site, at what altitude and age.
• Meteor showers with peak, radiant altitude and Moon interference.
• Live comets from the JPL Small-Body Database, with predicted brightness, altitude and solar distance, refreshed daily.
• Deep sky: over a hundred galaxies, nebulae and clusters with an image, angular size and the best night to shoot each.

WEATHER BY THE HOUR, NOT THE AVERAGE
A weather page built for imaging: one bar per hour from 20:00 to 04:00 with cloud cover in three layers, so you see when the sky opens and when it closes. Dew-point spread with an explicit warning when moisture is about to condense on the lens, peak wind that shakes the mount, minimum visibility, and the longest run of clear hours each night.

EVERY EVENT HAS A DETAIL PAGE
Altitude and azimuth hour by hour, the usable window, and suggestions for your lens: focal length, the exposure that freezes the sky's rotation, and whether tracking is needed. A card explains where the score came from, factor by factor.

WIDGET
Your nearest opportunities on the Home Screen in three sizes, with name, score and time. Tap a row to open its details.

YOUR LOCATION
Everything is computed from your current location or from a site you pick on the map and save by name, so you can compare your city sky with your dark-site sky. Sky darkness is estimated on the Bortle scale to adjust expectations.

WHAT LEAVES YOUR DEVICE
Events, Moon, planets and eclipses are computed locally and work offline. The network is used for two things only: fetching comet elements from JPL with no data about you, and fetching the weather forecast from Open-Meteo, which requires your coordinates. Your location and no other data about you are ever stored on any server.

SOURCES AND IMAGE CREDITS
Meeus algorithms and JPL elements for computation, JPL Small-Body Database for comets, Open-Meteo for weather, OpenStreetMap for the map. Deep-sky images are from Wikimedia Commons under Creative Commons licenses, each credited to its photographer inside the app.