The Russian telescope consists of a floating observatory with strings with spherical glass and stainless steel modules.
Measuring about a half-a-cubic kilometre, the Russian scientists said it is the biggest neutrino detector in the Northern Hemisphere.
Lake Baikal, which is the world’s biggest freshwater lake, was the perfect place to deploy the instrument.
Bair Shoibonov of the Joint Institute for Nuclear Research said: “Of course, Lake Baikal is the only lake where you can deploy a neutrino telescope because of its depth.
“Fresh water is also important, water clarity too. And the fact that there is ice cover for two to two-and-a-half months is also very important.”
And plans are in place to expand it to a full cubic kilometre in the coming years.