Solar StormAt the end of October 2003, a sudden solar storm hit the earth. A solar storm r

Solar Storm

At the end of October 2003, a sudden solar storm hit the earth. A solar storm refers to the large amounts of charged particles released into space______(51) the solar energy increases. The release of the energy______ (52) place along with the activity of the sunspots with a cycle of: 11 years. This time, the______ (53) of the storm exceeded expectations.

This______(54) of intense solar storm was caused by the eruption of a solar flare (闪光) and the ejection (喷发) of the solar corona (日冠) on October 28, 2003. Large amounts of charged particles moved 150,000,000 kilometers through space toward the ______(55) in 19 hours. They could affect aircraft roaming (漫游) in space.

The high-energy particles will______(56) some of the parts of an aircraft. They may also cause it to fail. High-energy particles can threaten the safety of an aircraft at a high orbit. If an aircraft orbits at a lower orbit, it is______(57) because it is under the protection of the earth's magnetic field.

A solar storm not only affects aircraft but also is a ______(58) to the environment and humans. The aerosphere and magnetic field of the earth can______(59) humans from ultraviolet radiation and X-rays. While most of the X-rays are absorbed after they enter the aerosphere (大气层), still a few can______(60) the ground.

The geomagnetic storm caused by this round of solar storm reaches its highest level on the two______(61) of the earth, which affects electricity supply of North America. Overexposure to______(62) threatens the health of passengers on planes flying over the Polar Regions. If we fly in the sky during such a solar storm, it______(63) we receive ten times the X-ray radiation. It's really damaging.

Scientists say a solar eruption is like the sun sneezing, which will make the earth______(64) a cold. Though this natural force is irresistible, scientists can still______(65) its movement accurately by monitoring. Facing successive solar storms, humans can't drop their guard.

A．since

B．when

C．until

D．though