Just as the space shuttle Endeavour was roaring off the launch pad in Florida last Sept. 30, the Kliuchevskoi volcano on Russia's remote Kamchatka Peninsula was clearing its throat.
By the time Baltimore-born astronaut Dr. Thomas D. Jones and his crew-mates flew over less than an hour later, the volcano was pouring a column of brown ash 10 miles into the sky. The plume would be carried hundreds of miles downwind.
It was the mountain's first major eruption since 1945, and only the second since 1737. For the shuttle crew -- on a radar-mapping mission designed in part to gather data on the world's 15 most dangerous volcanoes -- it was like winning the lottery.
"It was a very violent eruption, and people don't often get to see these things with remote sensing gear," Dr. Jones said. "We were over this thing three times a day, so we could look down its throat."
With the shuttle's sophisticated radar equipment, the astronauts peered straight through the dense ash cloud. Their colorful images show clearly in green where fresh lava was flowing down the mountain's rocky slopes.
The volcano studies were just a tiny part of a vast digital library of information returned to Earth by Dr. Jones and his colleagues on two missions in April and October last year.
He is scheduled to talk about them at 11 a.m. tomorrow in the Field House at Essex Community College, and show some of the thousands of photographs and radar images he helped gather during 539 hours in space.
The event is free and open to the public, part of the Franklin Square Hospital Center's 25th anniversary celebration. Those who wish to attend are asked to call (410) 682-7888.
Detailed scientific presentations from the radar missions are planned for the 1995 spring meeting of the American Geophysical Union, beginning May 30 in Baltimore.
Dr. Jones, 40, is a graduate of Kenwood Senior High School in Essex, and the Air Force Academy. He received his doctorate in planetary science from the University of Arizona in 1988.
He has not yet been scheduled for another space flight, but is training to serve as NASA's "capsule communicator" for shuttle flights beginning June 8.
The Kliuchevskoi eruption was serendipitous, but Dr. Jones' second Endeavour mission had long included plans for studies of 15 dangerous volcanoes, such as Washington's Mount Ranier, Italy's Mount Vesuvius and the Philippines' Mount Pinatubo.
With the shuttle's equipment, Dr. Jones said, "we can assess the history of these mountains and determine their hazard level."
By comparing radar images of Mount Pinatubo taken on successive shuttle flights in April and October of 1994, NASA scientists were able to identify mud and ash flows that have been advancing on villages and fields with each monsoon rain since the mountain erupted in 1991.
"We're assessing where the dangers are," Dr. Jones said.
Similarly, successive radar images of a volcano in Hawaii show clearly how the mountain's summit had moved between April and October -- swelling in preparation for the next eruption.
Ground movements as small as 2 to 4 inches can be spotted in the radar data, he said.
Here's a sampling of the wealth of information scientists are gleaning from Endeavour's data trove -- the equivalent of 40,000 encyclopedia volumes:
* By combining images taken on nearly identical repeat orbits, the astronauts were able to produce detailed, three-dimensional topographic maps.
While Venus and Mars have been mapped in detail by such radar techniques, Dr. Jones said, 60 percent of the Earth's land mass has not because the countries involved can't afford it.
L "We proved the technique works in a practical way," he said.
When Endeavour's radar gear is flown again in 1997, NASA hopes to gather the data needed to produce detailed contour maps for 80 percent of the globe's land mass.
* Hydrologists using Endeavour's radar data have been able to estimate the amount of water in the snowpack of the Alps and America's Sierra Nevadas with an accuracy of 95 percent. That kind of information is important to people responsible for flood control, water management and agriculture.
Currently, Dr. Jones said, such estimates are made by "a guy with a stick tramping around in the snow."
* Radar studies of forest land in Michigan's Upper Peninsula proved that radar can map not just the extent of forest cover, but also the distribution of different species of trees, their height and the volume of wood they contain.
* Oceanographers discovered that radar imagery can spot oil spills. Amazingly, Dr. Jones said, "you can spill as little as 10 liters [2.6 gallons] of oil in the ocean and detect it from 130 miles up."
Scientists also found they could distinguish between fish oil, fuel oil and algae. The technology could become a valuable tool for identifying polluters, but NASA's plans for a permanent, unmanned radar satellite are on hold due to budget cuts.
