Position: 89 13.8' N, 149 23' W, temperature - 14 C, air pressure 1030 hPa, wind 5 knots from ESE. Ice drift 0.2 knots towards southeast. Shooting seismic reflection all day. Replenish high pressure air supply by running the main engine for fifteen minutes every two hours. Recovered dredge #3 at 0500 hours - came up empty. The water depth was 2325 meter. Lowered the rock dredge again. Checked the radiation flux instruments . Sun time detector covered with rime and IR detector with snow.