It’s pretty hard to travel around in space because there are very few convenient ways of providing propulsion to a space ship. The most common method used in moving a ship in space are rockets, but they require that astronauts bring their fuel with them into space. As a result, rockets are heavy and expensive. The solution that many physicists propose is a solar sail, which would catch the light of the sun much like a canvas sail does with the wind, propelling a ship forward.
Conventional solar sails provide thrust by reflecting light off of their surfaces. This reflection generates a pressure on the sail which moves the ship forward. The trouble is that this makes it impossible to steer the sail. You are forced to move wherever the light takes you.
Scientists at my old alma mater: Rochester Institute of Technology (www.rit.edu) have a solution to this problem. A refractive sail could, conceivably, be used to steer a space craft. As the light passes through the refractive material, it is deflected at an angle due to Snell’s Law, precisely like the light bouncing off the bottom of a swimming pool.
Because of this angled flight, the light provides directional thrust when it impacts the other edge of the sail. By forming a sail from super-light refractive lenses, the astronauts of tomorrow could sail between the planets on a wind of light.
The universe is experiencing itself through variety
The sense of “I ” which should have been identified with the whole universe of your experience, was instead cut off and isolated as a detached observer of that universe. …this unity of organism and environment is a physical fact. But when you know for sure that your separate ego is a fiction, you actually feel yourself as the whole process and pattern of life.Experience and experiencer become one experiencing,known and knower one knowing. Each organism experiences this from a different standpoint and in a different way: for each organism is the universe experiencing itself in endless variety.
IN DECEMBER, a pair calling themselves “The Benevolent Fisted Rulers” offered up 4-hectare plots of Gliese 581 g, the most habitable exoplanet yet discovered, for sale on eBay.
Setting aside the ethics of exoplanetary land grabs, the move seems a touch premature. The alien world is 20 light years away and its very existence is not confirmed. Still, if the planet does exist, it is possible that it has some good exo-real estate.
Raymond Pierrehumbert at the University of Chicago examined the range of climates that Gliese 581 g might have and found one that would have a pool of water on one side, making it look like an eyeball. Even if further observations disprove the existence of Gliese 581 g, the work could help determine the habitability of exo-Earths still to be discovered.