Reference Resources

Good planning is half the battle in astronomy. The tools on this page help you explore the night sky, plan your observing sessions and make the most of every clear night — from planetarium software to essential weather and light pollution resources.

Logo	Description	Cost
	Clear Outside An essential weather planning tool designed specifically for astronomers. Clear Outside provides detailed hourly forecasts covering cloud cover, seeing, transparency, wind and humidity — all in one clear, easy-to-read display. Enter your location and it tells you exactly when your next clear window is likely to be. Available as a website and free mobile app.	Free
	Light Pollution Map An invaluable online resource showing light pollution levels across the UK and worldwide, based on satellite data. Simply zoom into your location to assess your sky quality and find darker observing sites nearby. Essential for planning observing sessions and understanding why some objects are harder to see from your back garden.	Free
	SkySafari Widely regarded as the gold standard mobile planetarium app, available for iOS and Android. Point your device at the sky and SkySafari identifies stars, planets, constellations and deep-sky objects in real time. Higher-tier versions add telescope control, detailed object information and an extensive observation log. A must-have app for any astronomer.	Free/Paid (plus & Pro)
	Stellarium One of the most popular and powerful free planetarium applications available, for Windows, Mac and Linux. Stellarium renders a beautifully realistic view of the night sky from any location and date, showing stars, planets, constellations, nebulae and more. An outstanding tool for planning observing sessions and identifying objects in the field.	Free on Desktop
	Stellarium Web The browser-based version of Stellarium — no download or installation required. Simply open it in any web browser and explore the night sky from your location. Ideal for quick planning sessions or for sharing with beginners and younger members who may not want to install software. Fully free to use.	Free basic version on Android/Paid
	Telescopius A superb free web-based planning tool aimed particularly at astrophotographers, though equally useful for visual observers. Telescopius helps you find suitable targets for your equipment, simulate your telescope and camera field of view, check object visibility and create custom target lists. Available via browser and as a mobile app for iOS and Android.	Free
	The Photographer's Ephemeris An indispensable planning tool for anyone wanting to capture the Sun, Moon or Milky Way in their images. The Photographer's Ephemeris shows the precise rising and setting positions and times for any location and date, helping you plan the perfect composition in advance. Available as a web app and paid mobile app for iOS and Android.	Free web version / Mobile app Paid
	Virtual Moon Atlas A free, detailed and actively maintained interactive atlas of the Moon for Windows, available in version 9.0. Visualise the Moon's appearance for any date and time, explore a database of over one million lunar features and browse a library of nearly 13,000 photographs. Also supports telescope control for computerised mounts. Used by the European Space Agency.	Free