Question 1
Prominences and solar flares present dangers to astronauts primarily because ________.
◦ they can overheat the spacecraft
◦ they disrupt communications on Earth
◦ they do not pose a danger to astronauts
◦ they pose a radiation danger from X-rays and gamma rays, but primarily from high-energy particle emissions
Question 2
If solar flares pose a danger to orbiting spacecraft and astronauts, how much warning is there for the danger?
◦ There is no warning; the radiation arrives at the same time as the feature is observed because they all travel at the speed of light.
◦ The primary danger is from high energy particles that travel at the speed of the solar wind 500km/s, so there is ample warning of 3-5 days.
◦ The danger is primarily from emission of neutrinos, which move at just below the speed of light; hence the warning is only a few seconds after a feature is observed.
◦ The danger is from high energy particles moving thousands of km per second, so the warning is a few hours.
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