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This is a cropped portion of a data plot showing the solar wind speed and density from December 1999 - December 2000. Please click on image for full view. In that full view, you can see that wind speeds remain between 200-800 km/s. It's possible, but rare, for solar wind to reach speeds above 800 km/s. All data was collected by the SWOOPS instrument.
Click on image for full size
NASA, ESA and LANL (the principal investigator of SWOOPS)

Characteristics of the Solar Wind

The sun is flinging 1 million tons of material out into space every second! We call this material solar wind.

The solar wind is very hot, 150,000°K! Because it is so hot, it is not a solid or a liquid or even a gas. Solar wind is plasma.

The solar wind is not very dense at all! Take a look at this picture for comparison with Earth's atmosphere. So even though the solar wind moves SUPER fast (normally in the range from 300 to 600 km/s), it wouldn't even ruffle your hair if you were to stand in a solar wind breeze!

The solar wind goes all the way past Pluto. Scientists hope the Voyager spacecraft will reach the end of the solar wind, the heliopause. Scientists sure are interested to see what the solar wind is like that far out!

Last modified March 9, 2001 by Jennifer Bergman.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA