Bone and muscle deterioration, radiation exposure, vision impairment — these are just a few of the challenges space travelers ...

This bone density loss can put the NASA astronaut at high risk of suffering fractures once back on Earth. The cardiovascular system adapts to microgravity by redistributing fluids in the body.

The temperature of the Earth depends on many factors including the concentration of greenhouse gases such as water vapour, methane and carbon dioxide. The Earth also radiates lower frequency ...

For millennia, Earth’s natural systems kept carbon levels ... carbonate protective coating like the shells and other body parts of coral, clams or oysters. Whales for example can absorb tons ...