Featured Research: The Radio Sun
When people think about the Sun, they usually don't have any idea that
the Sun is a strong source of radio waves. The solar radio group
in the Astronomy department (M. Kundu, S. White, V. Garaimov) uses the
radio emission from the Sun to study events happening in the Sun's atmosphere,
including the puzzle of solar flares (giant explosions) and how the Sun's
atmosphere is kept as hot as it is (milliions of degrees F). The picture
below shows an image of the Sun at the radio frequency of 5000 MHz (for
comparison, your FM radio signals are at a frequency of about 100 MHz).
This image was made with the Very Large Array, a well-known radio telescope
in New Mexico (used as a locale in many high-tech movies, including
Contact).
| |
| The brightest features (red) in this image have a temperature
of 1 million degrees and show where very strong magnetic fields exist in
the Sun's atmosphere. An optical image on this day shows sunspots under
these features. The green features are not as hot, but show where the Sun's
atmosphere is very dense. The disk of the Sun is at a temperature of 30000
degrees, and the dark blue features are cooler yet. The giant slash across
the bottom of the disk in this image is a feature called a filament
channel, where the atmosphere is very thin: it marks the boundary
of the South Pole of the Sun on this day.
There are more images of the radio Sun here. |
|
back to Astronomy |
 |
Past Features
|
