Star laser pointer: sharing the night sky with family and friends

What a class 2 laser can do under the stars

All our lasers have an output up to 1 mW, laser class 2 – the class intended for sale to the public in the UK. That is a sensible, family-friendly level, but it means the beam itself is faint. In very dark, humid air – a moonless night in the countryside, often with a little dew – the green beam can be faintly visible as a thin line towards the sky. In town, under street lights or on dry, clear evenings, you will mostly not see the beam at all.

So how do we use one for astronomy? Mostly in smaller, more personal ways:

• Close-up guiding: stand right behind your companion and point along your shared line of sight. On a very dark, humid night the faint green line can help them follow.
• Pointing at the horizon: put the dot on a tree, hill or roof below a bright planet or rising constellation – "look just above that chimney".
• Star charts and planispheres: point out objects on a chart or a projected sky map indoors before you go outside.
• Telescope finders: some amateurs use the green dot on nearby ground or objects to agree on a direction before swinging the telescope round.

Why green?

Green (532 nm) is the colour the human eye sees most easily, so it is the only sensible colour for night-sky use. The dot is visible at approx. 1 km in the dark and approx. 300 m at dusk (indicative). Red and violet reach much less far.

Range (indicative)

Our recommendations

• G3 Pro – rechargeable 18650 battery, two safety keys and an aluminium body that is comfortable to hold in cold hands. Our best seller.
• G1 Pro – same build plus a removable pattern lens for fun indoors.
• G2 Pro – compact and rechargeable for a pocket full of stargazing kit.

Tip: Li-ion batteries do not like the cold. Keep the laser in an inside pocket between uses and bring a charged spare, such as a PowerFox 18650 2-pack.

Stargazing safely

Before you point anywhere near the sky, look and listen for aircraft – including helicopters and drones – and never aim at them. In the UK it is a criminal offence to shine a laser at an aircraft or vehicle. Do not use a laser near airports or flight paths. Never point at people's eyes, and keep the laser away from children; it is not a toy. Read more on the laser pointer safety page.

A simple first evening

Pick a moonless night, drive or walk away from street lights, and give your eyes twenty minutes to adapt. Start with the easy wins: the Plough, Orion in winter, or a bright planet low in the sky. Stand shoulder to shoulder with your companion, point the dot at a tree or rooftop just below the object, and describe the shape from there. If the air is damp and the night very dark, you may catch the faint green line too.

Many astronomy clubs have their own rules about lasers at observing sessions – check before you bring one along. Enjoy the sky! More outdoor ideas: long range laser pointer.