In planetary astronomy and astrobiology, the Rare Earth hypothesis argues that the origin of life and the evolution of biological complexity, such as sexually...

None of these hypotheses can account for the high angular momentum of the Earth–Moon system. The prevailing theory is that the Earth–Moon system formed...

full of related hypotheses. For instance, Ferguson also asserted that the Sun was 30 miles in diameter and 3,000 miles away from Earth. He also disputed...

years: that early snowball Earths did not so much affect the evolution of life on Earth as result from it. In fact the two hypotheses are not mutually exclusive...

reasons) humans see no evidence. The following are some of the facts and hypotheses that together serve to highlight the apparent contradiction: There are...

the seventeenth century, philosophers and scientists have been forming hypotheses concerning the origins of our Solar System and the Moon and attempting...

to aerobic respiration Purple Earth hypothesis – Hypothesis that early photosynthesis reflected purple light Rare Earth hypothesis – Hypothesis that complex...

findings from poets, philosophers, historians, etc. In fact, many of the hypotheses are derived from the Egyptians, including Shepseskaf-ankh, a physician...

life on Earth. Other authors consider instead that life in the cosmos, or at least multicellular life, may be actually rare. The Rare Earth hypothesis...

him to estimate that Earth was about 75,000 years old. Other naturalists used these hypotheses to construct a history of Earth, though their timelines...