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At the bottom of the solar cycle, during the month of the winter solstice, come two contests spanning the limits of our MF/HF spectrum. The ARRL 160 Meter Contest ran last weekend and conditions were expected to be excellent. The other is the ARRL 10 Meter Contest -- what’s up with that being in December? Will there be anybody to work? Technicians should take advantage of their 10 meter privileges and find that a band completely devoid of activity on a weekday that suddenly springs to life at 0000 UTC this coming Friday. Find out a lot about propagation, the subject of this month’s ARRL Web quiz!

1) What makes sunspots appear to be dark?
a. Excess iron content
b. Absorption of solar radiation at visible wavelengths
c. They are cooler than the surrounding area
d. The Heisseluft-Rapp phenomenon

2) These astronomers were the first to document and study sunspots?
a. Sumerians
b. Etruscans
c. Chinese
d. Solarians

3) What satellite has provided new data about the Sun, improving our ability to predict solar behavior?
a. Hubble
b. Cassini
c. SOHO
d. GEOS

4) Where do sunspots from a new cycle appear on the Sun?
a. High latitudes
b. Equator
c. Corona
d. Penumbra

5) Which solar cycle peaked in 1959?
a. Cycle 17
b. Cycle 18
c. Cycle 19
d. 1959 was a solar minimum year

6) Once a spot disappears around the edge of the solar disk, how long would it take to reappear?
a. They never reappear
b. 13.5 days
c. 27 days
d. They do not move

7) What is the minimum value for solar flux?
a. Please don't say "minimum"!
b. 70
c. 67
d. 64

8) How does the current NASA prediction about activity in Solar Cycle 24 compare to Solar Cycle 23?
a. More active
b. Less active
c. About the same
d. The relationship is not predictable

9) Which type of propagation is most strongly dependent on solar activity?
a. F layer
b. NVIS
c. Tropospheric
d. Backscatter

10) What is the call sign of the author of the ARRL Propagation Bulletin and ARRL Solar Update?
a. K7RA
b. NM7M
c. K9LA
d. KL7RA

Bonus: What reverses at the peak of the solar cycle?

Answers

1. c - http://www.astronomycafe.net/qadir/q142.html
2. c - http://en.wikipedia.org/wiki/Sunspot
3. c - http://sohowww.nascom.nasa.gov
4. a - http://earthobservatory.nasa.gov/IOTD/view.php?id=35879
5. c - http://www.ips.gov.au/Educational/2/2/6
6. b - http://en.wikipedia.org/wiki/Solar_rotation
7. d - http://www.ips.gov.au/Educational/2/2/6
8. b - http://www.swpc.noaa.gov/SolarCycle/SC24/index.html
9. a - http://www.arrl.org/tis/info/k9la-prop.html
10. a - http://www.arrl.org/w1aw/prop/

Bonus: The solar magnetic field's North and South Poles change polarity -- http://science.nasa.gov/headlines/y2001/ast15feb_1.htm.

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