Couldn't find element LayerAd

Error finding content

The Solar Corona - Windows to the Universe

Shop Windows to the Universe

Earth Science Rocks! Select one of our four cool NESTA t-shirts from our online store, and express your love of Earth and space science!
Blending of an eclipse image (from the High Altitude Observatory) with a Yohkoh X-ray image (from the Yohkoh Science Team).
Click on image for full size
Image courtesy of the High Altitude Observatory, National Center for Atmospheric Research (NCAR), Boulder, Colorado,

The Solar Corona

Rising above the Sun's chromosphere , the temperature jumps sharply from a few tens of thousands of kelvins to as much as a few million kelvins in the Sun's outer atmosphere, the solar corona. Understanding the reason the Sun's corona is so hot is one of the many challenges facing solar physicists today. Because of the very high temperatures, the corona emits high energy radiation and can be observed in X-rays. The Earth's atmosphere absorbs X-rays, but satellites above the atmosphere, such as the Yohkoh spacecraft, can observe the Sun in these wavelengths. Shown on the left is a blending of a Yohkoh X-ray image (reddish colors) with an eclipse image taken by the High Altitude Observatory (gray-white colors) on November 3, 1994. Near the poles of the Sun, the corona is dark for both X-rays and white light. These regions are coronal holes and are the source of the solar wind that extends out into interplanetary space. The scattered white light shows the density of plasma in the corona. The large white regions extending out far from the Sun are helmet streamers, where the solar plasma has been trapped by the Sun's magnetic field.

Last modified May 10, 2010 by Randy Russell.

Shop Windows to the Universe Science Store!

Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

Windows to the Universe Community



You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Kelvin Temperature Scale

The Kelvin scale is a temperature scale that is often used in astronomy and space science. You are probably more familiar with the Celsius (or Centigrade) scale, which is part of the metric system of measures,...more

Solar Eclipses

An eclipse of the Sun occurs when the Earth passes through the Moon's shadow. A total eclipse of the Sun takes place only during a new moon, when the Moon is directly between the Sun and the Earth and...more

Helmet Streamers and the Magnetic Structure of the Corona

The gas in the solar corona is at very high temperatures (typically 1-2 million kelvins in most regions) so it is almost completely in a plasma state (made up of charged particles, mostly protons and electrons)....more

Last Solar Eclipse of the Millennium on August 11

The last solar eclipse of this millennium occurred on August 11, 1999. Amateurs and professionals alike used this opportunity to witness one of the most brilliant natural phenomenon. This was a total...more

Total Solar Eclipse - Coming Soon!

There is a solar eclipse coming to a theater near you! Well, Shakespeare said all the world's a stage, didn't he? There really will be a total solar eclipse on February 26th. The complete eclipse will...more

TRACING the Sun...

On March 30, 1998, the TRACE spacecraft will be launched. TRACE stands for Transition Region and Coronal Explorer. This spacecraft has four telescopes aboard that are sensitive to the extreme-ultraviolet...more

TRACING the Sun...

The TRACE spacecraft was launched April 1st at 9:42 p.m. EST from the central California coast. TRACE stands for Transition Region and Coronal Explorer. TRACE will operate in polar orbit about 400 miles...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF