Ephemis
Plan the night's best targets
Ephemis ranks deep-sky targets for your rig by how well they frame, how long they stay up in darkness, and how the Moon behaves — all computed on-device, wherever you set up.
Download on theApp StoreBuilt for the imaging night
Decide what to shoot before you set up the mount.
Framing-aware ranking
Targets are scored on how well they fill your rig's field of view — never too big or too small for your optic.
Moon avoidance
A per-night Moon track with broadband and narrowband avoidance curves surfaces the right targets even under a bright moon.
Real darkness windows
Astronomical, nautical, or civil twilight — Ephemis computes your true dark hours and how long each target stays usable.
Altitude charts
Full-night altitude curves with transit, meridian flip, your horizon limits, and the Moon overlaid.
My Targets projects
Save an imaging plan, track goal hours, log sessions, and watch tonight's visibility across your whole wishlist.
Fully offline
~16,800 deep-sky objects bundled in — NGC/IC plus Sharpless, Barnard, vdB, LBN and LDN. No signal needed at the dark site.
Syncs with iCloud
Your rigs, sites, and projects follow you across iPhone, iPad, and Mac through your own private iCloud.
Native on every Apple device
One SwiftUI app that feels at home on the phone in the field and the Mac at the desk.
Ranked, not just listed
Ephemis reads your sky and puts the night's best targets on top.
