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Space EnvironmentIs there energy in space? |
Sometimes a sudden, rapid, and intense variation in brightness is seen on the Sun. That is a solar flare. A solar flare occurs when magnetic energy that has built up in the solar atmosphere is suddenly released. On the Sun's surface are huge magnetic loops called prominences. When they touch, they short circuit each other, setting off explosions. The amount of energy released is the equivalent of millions of 100-megaton hydrogen bombs exploding at the same time! A solar flare contains high energy photons and particles, and is released from the Sun in a relatively short amount of time (a few minutes).
Here is a picture of magnetic loop, or prominence on the Sun. The colors
you see represent temperatures, from 360,000 degrees F (blue) to 2,700,00 degrees
F (red). Fifteen Earths could fit side by side inside one of the loops. When
these loops hit each other, they make a solar flare. Photo credit: Dr. Alan
Title/Stanford Lockheed Institute for Space Research and NASA.
Even though the solar flare stays close to the Sun (relatively speaking), the material thrown in to space by these explosions is radioactive. It is potentially dangerous to spacecraft and especially to people in space. Solar flares emit radiation across virtually the entire electromagnetic spectrum, from radio waves at the long wavelength end, through optical emission to x-rays and gamma rays at the short wavelength end. This radiation can corrode equipment, overload cameras or MICAS, and expose humans to dangerous levels of radiation.
After a solar flare: Shown here is an image of the Sun in soft x-rays. The white
(brightest) region on the right hand side shows post-flare loops, hot
loops that remain after a solar flare. Image from the Yohkoh Soft X-ray Telescope,
from NASA's Observatorium, http://observe.ivv.nasa.gov/nasa/exhibits/Sun/Sun_7.html
What is energy?
What interferes with radio waves?
What is an ion?
What's an electron?
What role does the Sun play in space missions like DS1's?
What makes EM radiation?
