M 101 - Pinwheel Galaxy

The Pinwheel Galaxy is a classic spring target and is ideally placed from our location around the middle of April. These were the first images taken with the Celestron EdgeHD 8. The small spikes visible on the stars kept me puzzled for a long time, and I was convinced for a while that they were down to poor collimation. In the end it became clear to me that they were spikes caused by the dew heater. With the heater switched off, the spikes disappear. So from now on it’s dew shield only, and no heater.