SDO solar image - 94 angstroms - Courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
satellite
radio propagation
Today's Space Weather
Sunday 28 August
last updated 27/2336 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 (28, 29 and 30 August) with some possibility of isolated C-class event. The effect of a solar sector boundary late on 28 August and that of a coronal hole from 29 August, may strengthen the solar wind stream from late hours of 28 August. This may raise geomagnetic activity to unsettled levels in late hours on 28 August and to active and minor storm levels on 29 and 30 August. Mild to moderate MUF depressions were observed during the UT day, 27 August. Mostly normal HF conditions may be expected on 28 August. Mild to significant depressions in MUFs and degradations in HF conditions may be observed on 29 and 30 August due to the expected rise in geomagnetic activity levels on these days.
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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