All of us every day use of plastic bags for disposal. We are so used to them that have no idea how you can use them for other purposes. But who would have thought that the humble garbage bag can play a key role in the mission to Mars?
In general, garbage bags are made of a polymer called polyethylene. It turned out that some species of polyethylene are well protected from most of the known forms of harmful cosmic radiation. Scientists have known about this for a long time, but the main hiccup was a question about the construction of such flimsy material of the spacecraft.
And it came to pass! Specialists from NASA invented a revolutionary material based on polyethylene, and called it RXF1. This material was stronger and lighter than aluminum.
"RXF1 - this is the first of its kind unique material that combines superior structural properties with excellent ability to escape" - says Nasser Bargoti (Nasser Barghouty), project specialist for protection from cosmic radiation at Marshall Space Flight Center (NASA’s Space Radiation Shielding Project at the Marshall Space Flight Center). Protecting astronauts from space radiation remains a major unresolved issue. Imagine a manned flight to Mars. Round trip flight takes 30 months. Out in the open space, the spacecraft with astronauts will be deprived of protection from radiation, which provides a magnetic field of the Earth. Some scientists believe that aluminum provides sufficient protection against radiation in the orbit of the Earth and when flying short distances. But aluminum is not enough protection when flying to Mars. Bargoti skeptical of the protection of aluminum and believes that fly to Mars in an aluminum boat impossible.
Plastic is a very attractive replacement: Compared to aluminum, polyethylene is 50% better protection from solar flares and 15% - from cosmic radiation.
The advantage of plastic is the fact that it creates a "secondary radiation" than sin heavy materials such as aluminum or lead. The secondary radiation is emitted by the shielding material. When a particle of cosmic rays slam into the atoms of the screen, they trigger tiny nuclear reactions. These reactions produce a rain of nuclear byproducts - neutrons and other particles that enter the spacecraft. This is similar to the situation when you are trying to protect themselves from the ball to the bowling alley with walls of needles sticking out: you hold the ball, but find yourself on fire igolok.Vtorichnaya radiation can be even more dangerous for astronauts than the actual space radiation!
In fact, heavy elements such as lead, although considered the best protection, producing much more secondary radiation than lighter elements, such as carbon and hydrogen. That is why polyethylene - good protection: it consists entirely of lightweight carbon and hydrogen atoms which reduces the amount of secondary radiation.
These light elements can not completely stop the cosmic radiation, but they can break down the particles of the radiation greatly reducing the harmful effects of radiation. All the details about the main events of the day widgets news let us know.