Space Weather

Definition

According to NASA, space weather is the dynamic conditions in the Earth’s outer space environment. It includes any event on the sun, in the solar wind, in near-Earth space and in our upper atmosphere that can affect the performance and reliability of space-borne and ground-based technological systems and through these, human life and endeavor.

Facts and figures

As society becomes increasingly dependent on space-based systems, it is vital to understand how space weather, caused by solar variability, could affect, among other things, space systems and human space flight, electric power transmission, high-frequency radiocommunications, global navigation satellite system (GNSS) signals, as well as the well-being of passengers in high altitude aircraft.

Some of the solar effects on Earth

Solar activities associated with Space Weather can be divided into four main components, which can have different impacts on Earth:

Solar flares (sudden brightening) are flashes of X-rays and ultraviolet rays that affect the ionosphere of the Earth almost immediately, with adverse effect upon communications and radio navigation.
Coronal mass ejections, also called CMEs, are large clouds of plasma and magnetic field that erupt from the sun, which can reach the Earth in 30 - 72 hours, setting off a magnetic storm and buffeting the Earth's magnetic shield, which could cause atmospheric heating and damage to pipelines and electric power grids. Severe magnetic storms resulting from coronal mass ejections are causes of failures of many geostationary orbit communication satellites, disturbances in the operation of satellite positioning systems, radio blackouts and power outages on Earth.
High-speed solar wind streams come from areas on the sun known as coronal holes, which are large, dark areas (representing regions of lower coronal density) when the sun is viewed in EUV or x-ray wavelengths. Such wind produces magnetic disturbances which can dump particles from space into the upper air, where they cause the northern lights, as well as the failure of many geostationary orbit communication satellites.
Solar energetic particles are high-energy charged particles, primarily thought to be released by shocks formed at the front of coronal mass ejections and solar flares. They can affect low-orbiting satellites to lose energy and fall.