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Space Weather

Before Space Weather

During Space Weather

After Space Weather

Related Content

The term “space weather” refers to the variable conditions on the sun and in space that can influence the performance of technology we use on Earth.

Space weather can produce electromagnetic fields that induce extreme currents in wires, disrupting power lines, and even causing widespread power outages. Severe space weather also produces solar energetic particles, which can damage satellites used for commercial communications, global positioning, intelligence gathering and weather forecasting.

The sun is the main source of space weather. Sudden bursts of plasma and magnetic field structures from the sun's atmosphere called coronal mass ejections together with sudden bursts of radiation, or solar flares, all cause space weather effects here on Earth.

Before Space Weather Occurs

 Space weather-related power outages can cause:

  • Loss of water and wastewater distribution systems.
  • Loss of perishable foods and medications.
  • Loss of heating/air conditioning and electrical lighting systems.
  • Loss of computer systems, telephone systems and communications systems (including disruptions in airline flights, satellite networks and GPS services).
  • Loss of public transportation systems.
  • Loss of fuel distribution systems and fuel pipelines.
  • Loss of all electrical systems that do not have back-up power.

Prepare Now

An emergency supply kit including an external battery, canned food, water, a flashlight, cleaning supplies and important papers.
  • Build an emergency kit
  • Make a family communications plan.
  • Learn more about preparing for power outages.
  • Be aware that most medication that requires refrigeration can be kept in a closed refrigerator for several hours without a problem. Check with your physician or pharmacist if you are unsure about your specific medication.
  • Keep your car’s gas tank at least half full. Gas stations rely on electricity to power their pumps.
  • Know where the manual release lever of your electric garage door opener is located and how to operate it.
  • Keep extra batteries or external chargers to charge your phone, laptop and other small electronics in the event of a power outage. Keep a car phone charger in your car.

During a Space Weather Occurrence

  • Keep your electricity usage as low as possible, which can help power companies avoid imposing rolling blackouts during periods when the power grid is compromised.
  • Follow the Emergency Alert System (EAS) instructions.
  • Disconnect electrical appliances if instructed to do so by local officials.
  • Do not use the telephone unless absolutely necessary. Keep phone lines open for emergency personnel during emergency situations.

After a Space Weather Occurrence

Throw out unsafe food:

Illustration of food in a refrigerator after the power has been off for several hours. Some food will need to be thrown out.
  • Throw away any food that has been exposed to a temperature of 40° F (4° C) or higher for two hours or more, or that has an unusual odor, color or texture. When in doubt, throw it out!
  • Never taste food or rely on appearance or odor to determine its safety. Some foods may look and smell fine, but if they have been at room temperature too long, bacteria that cause foodborne illnesses can start growing quickly. Some types of bacteria produce toxins that cannot be destroyed by cooking.
  • You can refreeze food in the freezer if the food is colder than 40° F and has ice crystals on it.
  • Measure the food’s temperature with a food thermometer if you are not sure that it is cold enough.

Last Updated: 05/31/2022

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