Anemometer placement

Why placement matters

The anemometer serves two distinct roles: it protects your equipment from winds strong enough to cause mechanical damage, and it ensures your observing sessions are not cut short by false readings from local turbulence. Both roles require that the measured wind accurately represents what your telescope actually experiences.

Three locations to avoid

1. House roof

If your observatory is at a lower level than the house roof, the wind speed measured on the roof is unlikely to bear any relation to what your telescope actually experiences. You may get valid readings during strong wind events, but you will also cancel sessions unnecessarily on calm nights where the house roof sees wind that never reaches the garden.

2. Roll-off observatory walls

Wind striking the side of the observatory structure creates significant measurement distortion depending on wind direction. Depending on whether the wind hits the front, side, or back of the building, the sensor may over- or under-report the speed at the telescope.

3. Dome sides

Air channelling between the anemometer and the curved dome surface causes inconsistent readings. The dome acts as a deflector, and the result — overestimate or underestimate — depends entirely on wind direction, making readings unreliable as a safety trigger.

Recommended placement

A free-standing post about one metre away from the observatory is a good starting point. It keeps the sensor clear of building-induced turbulence, represents the actual wind environment at ground level, and is easy to mount and service.

Adjust height to match the telescope's height if possible, and orient the post so that the prevailing wind direction hits the anemometer without obstruction.