Observing Skills · 8 of 12
Splitting Double Stars
How many stars is Mizar?
From the pair the eye can split to the pairs that need a telescope and a steady night — and one whose stars have moved in your lifetime.
You’ll be able to tell which double stars my eyes, binoculars or a small telescope will split.
Before this: Understanding Star Brightness (10 min)
Where and which night
Working out when this is best placed from where you are…
Where
Kept for this guide only, until you change it here — your map settings, and every other guide, stay as they are.
Print, play outside or present
Scan with a phone's camera, or open
Sources
- Washington Double Star Catalog (Mason et al., USNO), VizieR B/wds/wds — every separation and position angle
- Sixth Catalog of Orbits of Visual Binary Stars (ORB6), Porrima: Scardia et al. 2007
- Dawes, MemRAS 35, 137 (1867) — the resolving limit, 4.56″ over the aperture in inches
- SIMBAD — Johnson B and V of the companions the catalogue lacks
With a keyboard, focus the sky, aim it with the up and down arrow keys, and press Enter to drop the pin at the centre of the view; or press Show me.