Astronomy Picture of the Week – Necklace Nebula
The Necklace Nebula consists of a bright ring, measuring nearly 20 trillion kilometers across, with dense, bright knots of gas spread out in a way that resembles the diamonds in a necklace. The knots are not stars, they only glow due to the absorption of ultraviolet light from the two stars located in the center of the nebula.
Non-Rocket Spacelaunch – Launch Loop
A launch loop (also known as a Lofstrom loop) is a proposed design for a very efficient non-rocket spacelaunch method. It is a much simpler concept than the space elevator, but still more complex than tether propulsion systems such as the rotovator.