"Red sky may be gone; but it's impact will endure"
The Red Sky Phenomenon is a a phosphorous compound which has been released by the Visitors into Earth's atmosphere.
Red Sky is what its name implies: the sky is red instead of being blue.
We see the red sky after Anna experiences human emotion, removing the cloak on the V fleet and releasing the red sky into Earth's atmosphere.
In the 1st episode of Season 2, the captains of the 29 ships were surprised by the premature release of red sky, concluded that Anna herself has experienced human emotion, and were en route to see her personally. In a meeting with the captains, she says that no one, human or Visitor, can comprehend the magnitude of what is coming. It is unknown what happens afterwards. However, with her words "No one can comprehend the magnitude of what is coming," it seems Red Sky will do something horrific.
Although in Earth's atmosphere for a few days, one environmental scientist almost reached the truth on what Red Sky was in response, Anna ordered the termination of this scientist.
The release of Red Sky caused riots, mainly at the V Peace Ambassador Centers and possibly other V installations. Rioters blamed the Vs, demanding an answer for what it was because there was zero communication with Anna or any other Visitor leader.During the Red Rain, Anna's face appeared upon the screens on the belly of motherships across the world, telling them that she wanted to reveal the Red Sky's purpose when there was evidence of its success. According to Anna, the intended effect of Red Sky was to heal Earth's oceans, increase fertile lands and reduce the effects of global warming, reversing over a century of damage to the Earth's enviroment. However, Red Sky's actual purpose was to make Earth's environment more suitable for Visitor life by raining quantities of phosphorous onto the planet. Everything was caught in the effect: animals, plants, etc.
The red rain was planned especially to affect humans since the V's intended on inter-breeding with humans to create a new generation of V's, since large amounts of phosphorous are needed for a human to survive the pregnancy.
Despite being in the sky for four days, Anna says the effects of Red Sky will remain.
- The red rain is actually similar to the events recorded throughout human history where there has been accounts that red rain has actually fallen from the sky as blood red. One famous account was when red rain fell in Kerala, India.