Neutrinos are now being observed by the 10-meter South Pole Telescope. Neutrinos are thought to be dark energy or energy without mass. Under Einstein's cosmology constant, neutrinos are considered the energy amongst empty space, which now explains the acceleration of the expanding universe. The SPT is designed to focus on the light after the big bang, also known as cosmic microwave background radiation. They look at this to find galaxy clusters to try to find the mass of the neutrino.

The South Pole Telescope is used to put constraints on dark energy in order to see its mass. "The results are based on a new method that combines measurements taken by the SPT and X-ray satellites, and extends these measurements to larger distances than previously achieved using galaxy clusters." Galaxy clusters leave behind shadows when cosmic microwave background radiation is passed through it, which lets astronomers see the most massive clusters in the universe.


http://www.sciencedaily.com/releases/2012/04/120402093153.htm 

Seasons are controlled but the axial tilt of a planet relative to its orbit. Earth has an obliquity of about 23.5 degrees. This tilt causes the extremes of our seasons. "Along with daily rotations, this moderate obliquity ensures that the temperature differences between the coldest polar and hottest desert regions are not too extreme.". If a planet has a low axial tilt, then the planet might not be habitable because the planet's temperatures do not fluctuate. If a planet has too much of an axial tilt, then the extreme temperatures can also hinder the survival of life.

This is called the "Goldilocks"zone. The planet can not be too hot or too cold, but has to be just right. Simple life, however, is able to survive within these conditions. Some organisms and bacteria can ride out the extreme temperatures, but complex life would not be able to live on. 


http://www.space.com/14509-alien-planets-planetary-tilt-search-life.html