SDO solar image - 94 angstroms - Courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
satellite
radio propagation
Today's Space Weather
Friday 26 August
last updated 25/2321 UT
Solar activity has been very low over the last 24 hours. Solar activity is expected to stay at very low levels for the next three days (26, 27 and 28 August) with some possibility of isolated C-class event. Geomagnetic activity mostly stayed at quiet to unsettled levels on 25 August. Geomagnetic activity may rise to unsettled levels on 26 August due to the continued coronal hole effect. Geomagnetic activity levels may gradually decline to mostly quiet levels on 27 and 28 August. Mild to Moderate MUF depressions were observed during the UT day, 25 August. Mild to moderate depressions in MUFs and degradations in HF conditions may be observed on 26 August due to expected continued rise in geomagnetic activity levels on this day. Mostly normal HF conditions may be expected on 27 and 28 August.
What is Space Weather ?

Space weather refers to changes in the space environment, particularly the region between the Earth and Sun. The "solar wind" from the Sun stream past the Earth and is mostly deflected by the Earth's magnetic field, but variations in the solar wind cause changes in the Earth's magnetic field.

solar prominence

Occasionally, a huge release of magnetic energy, called a solar flare, occurs on the Sun. Flares can produce large quantities of x-rays which affect the Earth's atmosphere. They can also accelerate atomic particles (mostly protons) to very high speeds (a substantial fraction of the speed of light!). These high energy particles are dangerous to man and can reach the stratosphere where jetliners fly.

Most aspects of space weather affect us to some extent. The more our society becomes dependent on technology and the more we utilise space, the more we are affected by space weather. Some aspects of space weather are benevolent, and allow activities not otherwise possible such as long range radio communications. Some aspects are benign but fascinating such as the Aurora, and some are malevolent. Like terrestrial weather, it sometimes depends on the situation and the event.

The image below is an artists impression of the solar wind interacting with the Earth's magnetic field.

Solar wind
Combined image of active region 1520 shortly before it unleashed an X-class flare. The image is made up of light in the 171 Angstrom wavelength, and a magnetogram.
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