Topband: Sunspots and Cosmic Rays (spaceweather.com

[Bill Tippett]

*The following is from today's **http://spaceweather.com/
<http://spaceweather.com/> page.  Graphics will probably not appear but you
can see them if you click the link above.*

73,  Bill  W4ZV


*SUNSPOT CYCLE AT LOWEST LEVEL IN 5 YEARS: *The sun has looked remarkably
blank lately, with few dark cores interrupting the featureless solar disk.
This is a sign that Solar Minimum is coming.  Indeed, sunspot counts have
just reached their lowest level since 2011. With respect to the sunspot
cycle, you are here:

<http://www.swpc.noaa.gov/products/solar-cycle-progression>

The solar cycle is like a pendulum, swinging back and forth between periods
of high and low sunspot number every 11 years. These data from NOAA show
that the pendulum is swinging toward low sunspot numbers even faster than
expected. (The red line is the forecast; black dots are actual
measurements.). Given the current progression, forecasters expect the cycle
to bottom out with a deep Solar Minimum in 2019-2020.

Solar Minimum is widely misunderstood.  Many people think it brings a
period of dull quiet. In fact, space weather changes in interesting ways.
For instance, as the extreme ultraviolet output of the sun decreases, the
upper atmosphere of Earth cools and collapses. This allows space junk to
accumulate around our planet. Also,the heliosphere
<http://helios.gsfc.nasa.gov/heliosph.html> shrinks, bringing interstellar
space closer to Earth; galactic cosmic rays penetrate the inner solar
system *and our atmosphere* with relative ease. (More on this below.)
Meanwhile, geomagnetic storms and auroras will continue--caused mainly by
solar wind streams instead of CMEs. Indeed, Solar Minimum is coming, but it
won't be dull.

Realtime Space Weather Photo Gallery <http://spaceweathergallery.com/>

*COSMIC RAYS CONTINUE TO INTENSIFY: *As the sunspot cycle declines, we
expect cosmic rays to increase. Is this actually happening? The answer is
"yes." Spaceweather.com and the students of Earth to Sky Calculus have been
monitoring radiation levels in the stratosphere with frequent high-altitude
balloon flights
<http://onlinelibrary.wiley.com/doi/10.1002/2016SW001410/abstract> over
California. Here are the latest results, current as of Nov. 11, 2016:

<http://spaceweather.com/images2016/16nov16/stratosphere_11nov16.png?PHPSESSID=2boqpuphk9qjdfa6mrru43djg6>

Data show that cosmic ray levels are intensifying with an 11% increase
since March 2015.

Cosmic rays are high-energy photons and subatomic particles accelerated in
our direction by distant supernovas and other violent events in the Milky
Way. Usually, cosmic rays are held at bay by the sun's magnetic field,
which envelops and protects all the planets in the Solar System. But the
sun's magnetic shield is weakening as the solar cycle shifts from Solar Max
to Solar Minimum. As the sunspot cycle goes down, cosmic rays go up.

The sensors we send to the stratosphere measure X-rays and gamma-rays which
are produced by the crash of primary cosmic rays into Earth's atmosphere.
In this way we are able to track increasing levels of radiation. The
increase is expected to continue for years to come as solar activity
plunges toward a deep Solar Minimum in 2019-2020.

Recently, we have expanded the scope of our measurements beyond California
with launch sites in three continents: North America, South America and
soon above the Arctic Circle in Europe. This Intercontinental Space Weather
Balloon Network
<http://news.spaceweather.com/intercontinental-space-weather-balloon-network/>
will
allow us to probe the variable protection we receive from Earth's magnetic
field and atmosphere as a function of location around the globe.

Our work is completely crowd-funded. Everyone who sponsors a balloon flight
or buys an item from the Earth to Sky store
<http://earthtosky.net/shop> contributes
to this important body of knowledge. Thanks!