The ARRL Contest Branch has announced a new ARRL Contests Portal, which ARRL Contest Branch Manager Bart Jahnke, W9JJ, calls “a one-stop shop for all of your ARRL contest interests, offering access to everything from the starting bell of a contest to your post-event hard-fought certificate of accomplishment.”
Use the navigation tabs on the left to locate information about specific contests. Use the tabs at the top to submit logs, manage club eligibility lists, download certificates, and view other information for all contests. Jahnke said the new portal is still under construction, and information on specific contests and other contest-related content is being added every week.
Portal link: http://contests.arrl.org/
The sun's pockmarked surface is always shifting. Sunspots and solar flares rise and fall every 11 years, a cycle associated with regular reversal of the star's magnetic field. Huge quantities of plasma—known as coronal mass ejections—fly into space, which can disrupt satellites and other electronic signals if they reach Earth. More solar activity during the cycle also amplifies auroras and warms Earth's temperatures slightly. Yet careful study has shown that longer periodicities exist, too. The Gleissberg cycle, first identified in 1862, strengthens and weakens the 11-year cycle over the course of a century (shown in yellow). One paper posits that the Gleissberg pattern is caused by a slow swaying of the sun's magnetic pole. The Suess-DeVries cycle (green) lasts about 200 years, whereas the Hallstatt cycle (blue) runs on the order of 2,400 years. Still, the sun can also be erratic, making it tricky for physicists to predict future sunspots, says Alexei Pevtsov, an astronomer at the National Solar Observatory in Boulder, Colo.: “There's an element of randomness.”
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