This is a radar image of Galeras volcano in southern Colombia. Satellite images like this are valuable in studying volcanoes that can be dangerous to study on the ground. Galeras has erupted more than 20 times since the 1500s. Volcanic activity has been frequent in the last five years, including an eruption in January 1993 that killed nine people on a scientific expedition to the volcano summit. Chuck Wood of VolcanoWorld was on Galeras at that time but was not injured.
Galeras is the light green area near the center of the image. The active cone, with a small summit pit, is the red feature on the lower right edge of the caldera (crater) wall. The city of Pasto, with a population of 300,000, is shown in orange near the bottom of the image, just 8 kilometers (5 miles) from the volcano.
The image was acquired
by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/
X-SAR) aboard the space shuttle Endeavour on its 96th orbit of the Earth
on April 15, 1994. North is toward the upper right. The area shown is 49.1
by 36.0 kilometers (30.5 by 22.3 miles), centered at 1.2 degrees north
latitude and 77.4 degrees west longitude. The radar illumination is from
the top of the image. The false colors in this image were created using
the following radar channels: red represents the L-band (horizontally transmitted
and received); green represents the L-band (horizontally transmitted, vertically
received); blue represents the C-band (horizontally transmitted, vertically
received). Galeras is one of 15 volcanoes worldwide that are being monitored
by the scientific community as an "International Decade Volcano" because
of the hazard that it represents to the local population.
