Sometimes its rough sailing for Earth-circling spacecraft. They can become "drenched" in nasty bouts of space weather.
For instance, a weather satellite operated by the U.S. National Oceanic and Atmospheric Administration (NOAA) failed in 1982 due to space weather. In 1994, two Canadian communications satellites died, disrupting phone, TV and radio traffic. In 1998, space weather is thought to have crippled a Galaxy 4 commercial satellite, leaving millions of customers without service.
Even more recently, an expensive, super-secret spy satellite in geosynchronous orbit was blasted by a solar storm. Hardware that correctly oriented the spysat was fouled. The spacecraft began wobbling as ground controllers tried to regain control, only to compound the problem. It is believed the intelligence-gathering satellite was eventually put back on duty, but the event was a nail-biter for all concerned.
Solar surprises
The Sun is going through solar maximum at present -- an 11-year cycle in which increasing numbers of sunspots serve as signposts for possible episodes of
, or CMEs. A large CME can contain a billion tons of matter, spit out at high speed, that hits anything and everything in its way. On occasion, Earth is in the strike zone.Solar storm watching and forecasting is a pretty dicey business, said Joseph Kunches, acting chief of space weather operations here at NOAAs Space Environment Center (SEC). The current solar maximum hasnt coughed up as much activity as predicted, he said.
"The Sun has broken a pattern that existed for 150 years," Kunches said. "It looks like, from the sunspot numbers, the maximum was about a year ago. This March and April, while the sunspot number is high, it still has got a lot of catching up to do," he told SPACE.com.
Kunches said that he feels the Sun has reached a plateau in terms of uproarious behavior. "But its not unusual for a couple of years after sunspot maximum to get episodes of strong activity," he said.
"I wouldnt be surprised to see, perhaps, four or five episodes over the next year," Kunches said.
Streams of data
The key to space weather forecasting is timeliness of data.
Now planted in space are numbers of probes that make the job of understanding the Sun-Earth interaction feasible, such as the joint European Space Agency/NASA Solar and Heliospheric Observatory (SOHO) and the NOAA Geostationary Operational Environmental Satellite series, which includes the agencys Advanced Composition Explorer (ACE) and several pole-to-pole, Earth-circling spacecraft.
Streams of data from various sources -- ground, as well as space-based -- pour into the Space Environment Center.
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