Features
The sky is drawn as seen from where you are, right now: stars, constellations, planets and the Moon. Tap an object to see which way to turn, how many fists above the horizon to look and when it rises and sets. Lessons teach the sky step by step, and the stars in a night photo can be identified too.
Key features
- Sky map
- A view from the horizon: about 9,100 stars from the Yale Bright Star Catalogue (down to magnitude 6.5), lines and names of the 88 constellations, names of bright stars, the Sun, the Moon with its phase, the planets and selected deep-sky objects. Drag to turn; zoom with two fingers, the wheel or + −. The sky changes colour in daylight and twilight.
- Tonight
- Sunset, the time full darkness begins, the illuminated fraction of the Moon and a short note on the night. The "Visible now" list shows planets, the Moon, deep-sky objects visible to the naked eye and bright stars, with their best times.
- How to find it
- For the selected object: direction and height above the horizon, counted in fists at arm's length; brightness, distance, rise, highest point and set times, the light's journey and tips. Centre, Follow (keeps the object centred as time moves on) and Remind me (an .ics calendar file).
- Lessons
- 8 lessons: finding your way in the sky, Polaris, the Great Square of autumn, star-hopping to Andromeda, planet or star, phases of the Moon, the turning sky, brightness and magnitude. Each step turns the sky to the target and numbers the stars; "Show me" plays the time or the date. Progress is saved.
- Point at the sky
- On phones and tablets with an orientation sensor, the view turns with the device; it shows the name of the object in the middle and which way to turn towards a chosen target. An optional camera image in the background; it is not recorded.
- Identify photo
- Choose, drop or take a photo of the night sky; stars are found on the device and the photo's place in the sky is worked out. The result is an image marked with constellation lines, matched stars, names and deep-sky objects; "Open in sky" and a marked PNG.
- Time
- Hour by hour forwards and back, a slider from 24 hours before to 24 hours after, and "Now". In daylight or twilight, one tap goes to a dark hour.
- Place
- An offline list of cities (GeoNames, 1,389 cities), adding by coordinates and "Use my location"; on first launch the place is estimated from the device's time zone. Switch between saved places.
- Test yourself
- A star blinks in the sky; pick its name from four options. The best score is kept. "Measure with your hand" shows angles in the sky with the little finger, three fingers, a fist and a hand span.
- Search and view
- Search stars, planets, constellations (by local and Latin name) and deep-sky objects. Constellation lines, names, horizon and directions, and faint stars can be turned on and off; night vision turns the whole interface red so the eyes stay adapted to the dark.
- Samples
- On first launch there is the estimated city, a dark-sky place in the region and a sample photo that really is identified; samples can be deleted, and "Add samples again" brings them back.
- Files and backup
- Places, settings, lesson progress, photos and their solutions are saved and opened as a .stellavo file; a single photo can be saved too. The sky view and the marked photo are saved and shared as PNG. "Back up…" puts all Stellavo data and settings into a single file, and "Restore from backup…" brings them back on the same or another device.
- Works offline
- The star catalogue, the cities and the sky calculations are built in; lessons and photo identification also work without an internet connection. No account is needed.
Devices and browsers
- On a desktop, "Tonight" (lessons in Learn mode, photos in Identify photo mode) is on the left, the sky in the middle and details of the selected object on the right. On a phone and a tablet in portrait, the bottom bar holds Sky, Tonight, Details and More; the bar follows the current mode.
- "Point at the sky" appears only on touch devices with an orientation sensor; on iPhone and iPad, motion and orientation permission is requested. The camera image is optional.
- Night vision (red) keeps the screen from dazzling the eyes in the dark; turn it on with the R key or in the Display section.
Keyboard shortcuts
⌘ and ⌥ are used on macOS; Ctrl and Alt on Windows and Linux.
| Shortcut | Action |
|---|---|
| ← → ↑ ↓ | Turn the sky |
| + · − | Zoom in · out |
| Enter | Select the object in the middle |
| Esc | Clear the selection |
| [ · ] | One hour back · forward |
| N | Now |
| / | Go to search |
| 1 · 2 · 3 | Sky · Learn · Identify photo |
| R | Night vision (red) |
| Ctrl/⌘ O · S | Open library file · save library |
| Ctrl/⌘ Z · ⇧ Z | Undo · redo |
On a touchscreen, drag with a finger to turn the sky, pinch to zoom and tap an object to select it; menus and dialogs open from the bottom.
Get Stellavo
Try it in the browser without installation; for continued use, purchase the version for macOS, Windows or Linux.