What Hams can expect on August 21stOn Monday, August 21, 2017, a total solar eclipse will be visible in totality within a band across the entire contiguous United States; it will only be visible in Canada and other countries as a partial eclipse. The last time a total solar eclipse was visible across the entire contiguous United States was during the June 8, 1918 eclipse. In the Vancouver, BC area we can expect about 90% coverage of the sun.
A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the sun for a viewer on Earth. A total solar eclipse occurs when the moon's apparent diameter is larger than the sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometers wide.
This eclipse is the 22nd of the 77 members of Saros series 145, which also produced the solar eclipse of August 11, 1999. Members of this series are increasing in duration. The longest eclipse in this series will occur on June 25, 2522 and last for 7 minutes and 12 seconds.
Not since the February 1979 eclipse has a total eclipse been visible from Canada and the mainland United States. The path of totality will touch 14 states, though a partial eclipse will be visible in Canadian Provinces and many other US states. The event will begin on the Oregon coast as a partial eclipse at 9:06 a.m. PDT on August 21, and will end later that day as a partial eclipse along the South Carolina coast at about 4:06 p.m. EDT.
Ward Silver N0AX writes about the Solar Eclipse and Amateur Radio:
The optical effects of an eclipse are relatively obvious and well-understood. Partial solar eclipses are fairly common and lunar eclipses even more common. Not many of us have witnessed totality, but most people have seen some type of eclipse. What very few people have observed is the effect an eclipse has on radio propagation. In just over 90 minutes there are expected to be dramatic changes in both the ionosphere and HF propagation.
Read the Nuts and Volts article at
Befitting of our hobby, there will also be a Solar Eclipse QSO Party. The Solar Eclipse QSO Party (SEQP) is a HamSCI-ARRL sponsored operating event to generate data to study ionospheric changes during the eclipse. Contest logging program N1MM has published a built-in SEQP logging module. Simply select "ECLIPSE" for log type: http://hamsci.org/seqp
I hope you have Monday, August 21st circled on your calendars in bright red ink... It may be a Ham Radio event to remember.