NASA Logo, National Aeronautics and Space Administration
Skip Navigation (press 2)
Student Observation Network Header

STORM SIGNALS

From Satellites: GOES 5-min X-ray Plot

Live Data

GOES 5-min X-ray Plot (real-time)

A complete list of real-time data links is located in the Space Weather Resources section.

The GOES satellites provide information about the strength of x-ray emissions from the Sun. The Sun is constantly producing x-rays, so you are looking for significant increases in the intensity of x-ray above a background. Scientists have developed a simple rating system for solar x-ray activity. They have created five levels; A, B, C, M, and X. A is the lowest level, B is 10 times more powerful than A, C is 10 times more powerful than B, M is 10 times more powerful than C, and X is 10 times stronger than M. So this makes an X event 10,000 times stronger than A. In addition, each level can be further divided from 1.0 to 9.9. This means you could have a C2.3 event, or a B7.9 or an M6.5 However, since X is the highest level, the numbers don't stop at X9.9. In October 28, 2003 there was an X17.2 flare followed several days later by an approximately X28 flare (actually it was so strong it was hard to measure). These are the biggest flares ever measured.

The GOES x-ray plots for solar storms on May 27 and 28, 2003 are shown below.

Data from the GOES x-ray instrument on May 26, 2003.

Two GOES satellites record solar x-ray emission, GOES 10 and GOES 12. The red plot from GOES 12 is the one we want. It shows that normal solar activity was in the B range. There were 6 flares in the high C or low M range May 26 and 27. Then late on May 27 and shortly later on May 28 two X-class flares erupted. Images from SOHO showed that both sent coronal mass ejections toward Earth. Interestingly, the second CME traveled faster than the first and collided with the first. These CMEs disturbed the Earth's magnetosphere significantly and produced auroras as far south as Virginia. In general you want to be alert for M-class and X-class flares. It is also important to find out if these flares were on the side of the Sun facing us. Flares from the side of the Sun facing us are more likely to disturb the Earth's magnetosphere than flares that erupt from the edges (as we look at the Sun). The SOHO website and the Latest Events website will help us determine where the flares occurred and whether a coronal mass ejection occurred with the flare. But first you should check for a radio signal from the Sun detected by the WAVES instrument on the WIND satellite.

Next Step: Wind Waves »

NASA Logo - nasa.gov