In research aiming to understand how life might develop, scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets.
“The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens,” said Aditya Chopra from ANU.
“Early life is fragile, so we believe it rarely evolves quickly enough to survive.”
“Most early planetary environments are unstable. To produce a habitable planet, life forms need to regulate greenhouse gases such as water and carbon dioxide to keep surface temperatures stable.”
About four billion years ago, Earth, Venus, and Mars may have all been habitable. However, a billion years or so after formation, Venus turned into a hothouse and Mars froze into an icebox.
The Case for a Gaian Bottleneck: The Biology of Habitability
Nextbigfuture notes that
the fact that Mars or Venus might not have life that our solar system has at least ten planets, moons and dwarf planets with liquid oceans. They likely have at least microbial life. We also just found a new planet in the solar system that is about 4 to ten times bigger than earth.
Planet Nine, it "has a mass about 10 times that of Earth and orbits about 20 times farther from the sun" than Neptune. That means "it would take this new planet between 10,000 and 20,000 years to make just one full orbit around the sun," according to Caltech.
Researchers Konstantin Batygin and Mike Brown haven’t actually seen the planet, but other research helped lead them to conclude that there is one. Basically, they found that certain objects in the Kuiper Belt — the field of icy objects and debris beyond Neptune — had orbits that peculiarly pointed in the same direction.
from Next Big Future http://ift.tt/1VkKNo5
via IFTTT
Telescopically 