National Weather Service United States Department of Commerce

 

Sun Image Space Weather Sun Image

 

Space weather is becoming a very important aspect

of the National Weather Service, and will continue to

grow as we gain a better understanding of the physical processes of

the sun and their effects here on Earth as well as in space itself.

 

Space weather can have significant effects to humans on Earth

as well as in space due to the growing of number of satellites

in space, power grids on earth, use of Global Positioning Systems (GPS),

as well as commuter air travel and space travel.

 

Solar flares, coronal holes, and coronal mass ejections (CME's) can emit

large bursts of radiation, high speed electrons and protons, and other

highly energetic particles that are released from the sun, and are

sometimes directed at Earth. These particles and radiation can damage

satellites in space, shut down power grids on earth, cause GPS outages,

and have serious health concerns to humans flying at high altitudes on earth,

as well as astronauts in space.

 

There are 3 main categories of space weather storms: geomagnetic storms,

caused by CME´s and the high speed wind from coronal holes,

that can create beautiful auroras, as well as cause problems for

electrical systems, satellites, GPS, and radio systems; solar radiation storms,

associated with both flares and CME´s, that can be a danger to the health

of astronauts and to people flying at high altitudes, and also cause problems

for satellites and radio systems; and radio blackouts, caused by solar flares,

resulting in communications and GPS outages.

 

For this reason, the Space Weather Prediction Center (SWPC) located

in Boulder, Colorado issues a variety of space weather forecasts and

warnings daily to alert those concerned with these effects.

Here are some helpful shortcuts:

 

Images:

 
Sunspots

Sunspots are areas on the sun in which the temperature is cooler than its surroundings, causing a dark spot to appear on the surface of the sun. Theyare areas of strong magnetic fields that are thousands of times stronger than the Earth's magnetic field.

 

Sunspots usually come in groups and contain two sets of spots. One set will have a north (or positive) magnetic field, while the other will have a south (or negative) magnetic field. Sunspots can appear randomly on the face of the sun, and remain for several days or weeks, or be gone in just a few days.

 

The number of sunspots that appear on the sun's surface changes on a nearly regular cycle called the "Sunspot Cycle" or "Solar Cylce." This cycle on average lasts about 11 years. Every other solar cycle, there is a 22-year cycle in which the poles on the sun switch. At the end of this cycle, the "north pole" will become the "south pole," and after another 22-years, vice versa.

 

The position of where sunspots occur also changes in relation to the sunspot cycles. At start of a new cycle, solar minimum, the sunspots appear in the higher latitudes. As the sunspot cycle progresses toward solar maximum, they begin to appear toward lower latitudes, and near the equator.

 

As the sun progresses to the end of the solar cycle, the sunspots can appear anywhere on the face of the sun, but mostly in lower latitudes. Follow this link to see a plot of the sunspots positions on the sun.

Sunspot Cycle 24 Progression:
Sunspot Cycles and Anomalies (Based on 1901-2000 Average) through 2013:

Sunspot Graph      Sunspot Anomalies Graph

( click on image to view full size )
Sunspot data provided by:
WDC-SILSO, Royal Observatory of Belgium, Brussels
Other Astronomy Interests
Sun/Moon Info:
Meteor Showers:
Iridium Flares:
  • Heavens-Above 
    Predictions of iridium flares as well as ISS and other satellites.
Iridium Flare      Iridium Flare 
Photographs courtesy of Lee Robertson (Cold Bay, Alaska)
Noctilucent Clouds (NLC):
Noctilucent clouds      Noctilucent Clouds 
Photographs courtesy of Lee Robertson (Cold Bay, Alaska July 13-14, 2005)