In the last week of December 2025, the IceCube crew completed drilling and installation for the first IceCube Upgrade string. More on this news can be read from the IceCube web page (link). The photograph above shows a group of drillers (including scientists) on the day shift after deploying more than half of the modules into the hole. (Photograph credit to Colton Hill, IceCube/NSF)
IceCube Upgrade is an upgrade of IceCube. A total of seven strings, each with upgraded optical modules and calibration modules, will be deployed near the DeepCore. The upgraded optical modules have a higher photon detection efficiency than the previous IceCube optical module. With the dense distribution of these sensor modules, IceCube will gain higher sensitivity to study neutrino oscillations. The deployed calibration modules will provide critical data to understand how photons travel through the ice, improving models for high-energy neutrino event reconstructions.