top of page

Low Temperature Limitations of the eQuinox, SeeStar S50 and the Dwarf 2 Smart Telescopes

I have operated the Unistellar eQuinox 2, SeeStar S50 and Dwarf 2 in cold weather during the fall and winter this season. One of the questions that I had about the smart telescopes was their true operating temperature range. For example, Unistellar specifies an observation range between 14 and 104 degrees Fahrenheit for the eQuinox. They also specify that in a very cold environment the telescope should be covered in insulation. The main effect was described as the battery draining faster. In my experiment, I used a portable power supply to continuously charge the battery to avoid the fast draining issue. What I observed was as the temperature dropped to 40 degree Fahrenheit, the telescope began to respond slowly to commands. at 38 degrees, it slewed downward rather than pointing upward to an object located at 51 degrees. It then shut itself off. I pressed the on button and telescope was able turn on and to connect to my smartphone, but then shut itself off after a few minutes. I took the telescope indoors to warm it up and to charge it. The scope would not start up or take a charge for a few hours until it warmed up to room temperature.

My experiences with the SeeStar and Dwarf 2 were better. I was able to use both telescopes at zero degrees Fahrenheit. The Dwarf 2's stacking slowed down considerably. However, it did record all of the frames correctly and I was able to stack them with Siril. Frankly I was pleasantly surprised that the SeeStar and Dwarf 2 both worked at zero degrees. I would have liked to test them at even lower temperatures but their were no clear nights where the temperature fell below zero degrees in my area.

The eQuinox 2 is much heavier than the SeeStar or Dwarf 2, so it will require more energy to operate. The eQuinox 2 battery is much larger than the SeeStar and Dwarf 2 batteries and should be capable of about 11 hours of operation at room temperature. It is a Li ion battery and its capacity and charge rate do diminish with temperature. It was surprising to me how rapidly its capacity and charge rate did degrade at 40 degrees F. A 5 V 2 amp charger should have been able able to keep up with its energy needs given that the battery started out fully charged. It is possible that the battery capacity could have degraded significantly in the 5 months since I purchased it. However, because I own an electric car I am knowledgeable about battery conditioning. I diligently followed Unistellar's guidelines for battery care for the telescope plus I did not allow the telescope to be stored for long periods since I used it every clear night since it arrived. I don't think insulation is the solution, and I am hesitant to try it. If I do run the telescopes temperatures below 50 F again, I might try a portable heater.

4 views0 comments


bottom of page