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The Active Sun
The Solar System >
Do
you remember in school seeing those pictures of the sun with little spots?
Those spots, cleverly called "sunspots," are actually big enough
to cram an Earth or two into. They are cooler areas of the sun’s
surface where stressed-out lines of magnetism are snaking in and out.
During times of high solar activity - called Solar Max - there are a lot
more of these spots than when the sun is more relaxed and laid-back.
This is a Solar Max year and, as expected, there are a load of spots.
But wait! There’s more!
During Solar Max there is also an increased amount of "flares,"
gargantuan explosions on the sun’s surface which spew particles and
radiation out into space.
These flares seem to be related to the latest and most exciting discovery
in solar activities called Coronal Mass Ejections (CME). These are solar
burps belching prolific amounts of energy and particles. But these burps
are so big and magnificent as to defy description; you‘ll have to
see one to to even begin to imagine their size (see below for websites).
When the radiation and particles crash into our atmosphere,
they do al kinds of interesting things. They fire up aurorae - the Northern
Lights. They interfere with radio communications of all types. They break
up cellphone conversations. They cause annoying noise on your AM-FM radio.
They destroy satellite computer circuitry rendering them useless. They
may actually set off an automatic garage door opener!
And
the pesky radiation actually heats the upper atmosphere enough to expand
it so that low-altitude satellites, normally free from the drag of air
molecules, are slowed a little and run the risk of crashing back into
earth.
NASA has to be extra aware of the activity on the sun during Solar Max
when planning and launching the Shuttle for all those reasons.
Want to see spectacular images of all these solar phenomena and more?
The SOHO satellite website has up-to-the-moment images of the sun as seen
in visible and x-ray and ultraviolet, and some stunning movies of the
CMEs. You can also get a nifty solar screensaver!
Until next time, clear skies!
Mark Ritter is a high school astronomy instructor and can be reached at
ritter@firstlightastro.com.
Posted by Administrator at 2000.06.25 09:29 AM | Comments (0)
