Scientists from China dealt a blow to the quest for discovering alien organisms inhabiting worlds elsewhere in the cosmos, saying that Earth was ‘unusual’ in its ability to host liquid water—one of the key ingredients for life as we know it.

A study presented in the Journal Nature Geoscience explains how without atmospheric greenhouse gases—as those on Earth—energy required to “defrost” distant alien planets of moons, and turn them into a living environment is nearly impossible, reducing the probabilities of finding life elsewhere in the cosmos.

A new scientific study has revealed details for the type of planets in the cosmos which are capable of sustaining life as we know it.

Scientists from the Peking University in China have come up with a 3D climate model that helps simulate the planetary evolution of ICY worlds, which according to many experts may have had the necessary conditions to sustain life as we know it.

Scientists argue how icy planets and moons in the universe have gone through “melting phases” in their long history, allowing the existence of liquid water on, or below their surface.

A few of such examples are Saturn’s moon Enceladus and Jupiter’s moon Europa which are considered as ideal candidates in our solar system to meet the necessary requirements to host “Alien” life.

But the new study by scientists from China argues how icy worlds may have been forced to skip the “habitable phase” due to the massive amount of energy required to melt their surface.

The new study argues how our planet is a habitable world as when it was going to its defrost phase, less solar energy was required to melt ice since the planet had help from volcanic eruptions that gave rise to more planet-warming greenhouse gases.

Scientists found that on other planets, once a host star became hot enough to melt ice on a planet or a moon, its energy transitioned too fast into a “greenhouse state” which eventually evaporated any liquid water in the process.

Experts from the Peking University said:

”We find that the stellar fluxes that are required to overcome a planet’s initial snowball state are so large that they lead to significant water loss and preclude a habitable planet.”

This means that some icy planets or moons, may never, ever pass through a habitable Earth-like state, drastically reducing the probability of life in the universe.

The team of experts further explains how they believe how Europa and Enceladus will most likely transform from giant iceballs into fireballs when our Sun reaches its red giant phase, in billions of years.

”…the examples for such planetary bodies are the icy moons Europa and Enceladus, and certain icy exoplanets orbiting G and F stars. We find that the stellar fluxes that are required to overcome a planet’s initial snowball state are so large that they lead to significant water loss and preclude a habitable planet.”

“Specifically, they exceed the moist greenhouse limit, at which water vapor accumulates at high altitudes where it can readily escape, or the runaway greenhouse limit, at which the strength of the greenhouse increases until the oceans boil away. We suggest that some icy planetary bodies may transition directly to a moist,”…wrote experts in their study published in the Journal Nature Geoscience.

Source: Abrupt climate transition of icy worlds from snowball to moist or runaway greenhouse