Arctic rivers and runoff from the land pour vast volumes of freshwater into the Arctic Ocean, influencing seawater salinity, sea-ice formation and ocean circulation, thereby playing an important role in regulating Earth’s heat balance.
NASA and the China National Space Agency (CNSA) plan to send astronauts to Mars as early as the next decade. Naturally, this ambitious goal requires a great deal of planning, research, and the anticipation and preparation for all potential challenges in advance. Among them, astronaut health and safety are paramount. In addition to the hazards associated with the long transit times - radiation and the effects of long periods in microgravity - there's the issue of Mars itself. Aside from exposure to elevated radiation levels, Martian gravity is about 38% of Earth's.
