Star Map Guide
Interactive sky chart for planning and navigating your observations.
Overview
The Star Map is a full-sky chart showing stars, deep-sky objects, planets, constellations, and coordinate grids. It opens centered on what’s visible tonight from your default location. Use it to explore the sky, search for objects, plan observations, and generate star-hop paths to find targets at the eyepiece.
Header Controls
Navigation
Mouse
Keyboard
Touch
Search
Type in the search bar to find objects. Results appear as you type.
Click a result to center the map on that object.
Time & Location
Date & Time
Set the observation date and time manually, or use the quick presets:
Step forward or backward with the 1d, 1h, and 10m buttons.
Location
Choose from your saved locations, built-in presets (cities and observatories worldwide), or enter latitude and longitude manually. Your default location is used automatically when you open the map.
Local Sidereal Time
The LST display shows which part of the sky is on the meridian. Objects with RA close to the current LST are highest in the sky and best placed for observation.
Settings
The settings panel has three tabs:
Markers
- Deep-sky catalogs — Toggle Messier, NGC, and Caldwell objects individually
- Star names — Show or hide labels on bright stars
- Milky Way — Show or hide the Milky Way band
- Star magnitude limit — Slider (3–12) to control how many faint stars are rendered. Higher values show more stars but may slow rendering.
- DSO magnitude limit — Slider (5–14) to filter deep-sky objects by brightness
- Satellites — Toggle live satellite tracking with categories: Space Stations, Bright Satellites, Starlink, and Amateur Radio. Includes trail and label options.
Grid
- Coordinate grid — RA/Dec (equatorial) or Alt-Az (horizontal)
- Constellation lines — Stick-figure outlines connecting bright stars
- Constellation boundaries — IAU official constellation borders
- Ecliptic — The Sun’s annual path through the zodiac
- Horizon — Show the local horizon line (requires location and time)
- Realistic sky — Varies the background brightness based on the Sun's altitude to simulate twilight and daylight
- Sky sectors — Show a numbered sector grid for catalog reference
Star Hop
- Minimum Brightness — Magnitude limit for starting stars (brighter = easier to find)
- Finder Circles — Choose Telrad, Rigel QuickFinder, or custom one/two circle finder with configurable FOV
- FOV calculator — Compute the true field of view from your eyepiece and finder specs
- Show Alt-Az directions — Show directional hints for Dobsonian telescopes
- Reverse directions for finder — Flip directions for use with a finder scope
View Modes
Dark background optimized for screen viewing. Default mode.
White background with black objects, like a printed star atlas.
White background with enhanced star sizes, designed for printing.
Red-on-black to preserve your dark-adapted vision at the telescope.
Circular polar projection centered on the celestial pole, like a classic rotating planisphere.
Object Interaction
Hover over any object to see a tooltip with its name, type, magnitude, and coordinates.
Click an object to select it. The header shows the object name and a Star Hop button appears for deep-sky objects.
Right click anywhere for a context menu with options to center, zoom, copy coordinates, or place a finder circle.
Action Buttons
When you select an object, action buttons appear below the object info:
Star Hop
Star hopping helps you navigate from bright, easy-to-find stars to your target object step by step.
1. Click a deep-sky object to select it.
2. Click the Star Hop button in the header.
3. The map automatically generates a path from a bright naked-eye star to your target, using recognizable star patterns as waypoints.
The overlay shows:
- Starting star (bright, easy to find)
- Waypoints along the path
- Your target object
- Dashed path line connecting the steps
- Telrad or finder circles at each waypoint
- Click to try a different starting star
Configure the starting-star brightness, finder type, and FOV in Settings → Star Hop.
Keyboard Shortcuts
Notable Features
Galilean Moons
When you zoom in close to Jupiter (FOV below 2°), its four Galilean moons — Io, Europa, Ganymede, and Callisto — appear at their current positions. Their positions update with the selected date and time.
Variable Star Designations
Variable stars display their standard designations (e.g. R Leo, RR Lyr, V603 Aql) alongside Bayer and Flamsteed names when you zoom in.
Export
Use Save to PNG in the View Mode menu to download the current view as a PNG image. The export uses whatever view mode is active, so switch to Atlas or Print mode first if you want a light background suitable for printing.
