Road to Ubar Pa - Nicholas Clapp [21]
An earlier version of this radar, SIR-A, had been borne aloft on a 1981 mission of the shuttle Columbia. Ron had been a principal scientist on the project and savored relating the story of some of the first images to be analyzed. Taken over Africa, they were of northern Sudan's pancake-flat Selima sand sheet.
"The immediate thought was that somebody had grabbed the wrong roll, that this was really someplace else," Ron recalled. "The radar images didn't look anything like what we understood to be the Selima's bland surface."
It was the right roll. What those images recorded was not the veneer of the windblown sand sheet but a denser surface buried beneath it. The radar saw right through the sand as if it weren't there, revealing a hidden landscape of streams and rivers, now dry and buried but once filled with the torrential runoff of monsoon rains. The radar had reached back hundreds of thousands of years and taken a snapshot of a vanished land.
Ron's team traveled to Egypt and Sudan to "ground-truth" the Selima images. In a totally featureless landscape, they plotted where on their radar image two buried rivers converged—a good place for a campsite. They dug down through the sand and, sure enough, found riverbank contours and Stone Age artifacts.
"With Ubar, say it was buried. We could pick up what?"
"A lot, as long as it was reasonably near the surface."
"Meaning?"
"Six feet down, no problem. Theoretically, the radar can penetrate up to five meters—eighteen feet, that is—of very dry sand."
"And what would we see? Walls? Buildings?"
"It would have to be something pretty sizable. But sure, structures should show up, as long as they were on the order of thirty meters across. That's the limit of SIR-B's resolution ... the size of a pixel."
I nodded, not entirely sure what a pixel was.
Walking me back to the lab's main gate, Ron promised to arrange a meeting with Charles Elachi, who not only headed up JPL's Radar Imaging Geology Group, but was director of the entire ambitious NASA SIR-B shuttle project.
A week later we were in Charles's office. And if there was an occasion for intimidation, this was it. Here was a scientist's scientist, at thirty-six a holder of Ph.D.s in planetary geology, electrical engineering, and quantum physics. He had also grown up in Lebanon and was well aware that in the Middle East fact and fancy often became hopelessly intertwined. I admitted this to be the case with Ubar, but said I felt that, as sources, Bertram Thomas and Claudius Ptolemy could be trusted.
"Okay, how about you?" Charles said to me. "You think this place Ubar really exists?"
I had to be honest. "Frankly? I don't know."
"That's a perfectly good answer," Charles replied, without a hint of hesitation. "What's science for, if not to find out what exists or doesn't. Right, Ron?" Ron nodded, and Charles continued, "But say we did this, we went looking for Ubar with our spaceship, it would have to be unofficial, you understand. With you, we're not exactly dealing with ..."
I could complete the sentence: "...an academic institution."
"No offense, you understand, It's just..." Ron interjected.
"Oh, my, no offense at all," I assured them. "Listen, I'm amazed you're even considering this."
"What if," Ron suggested to Charles, "we made Ubar a target of opportunity? If we're not in trouble on anything else, that is."
"We could. Yes, we could certainly do that," Charles agreed, and the meeting was over.
As Ron and I walked away down one of JPL's endless corridors, I wasn't quite sure what the upshot of the meeting was, but I suspected that the space shuttle's trajectory might just happen to intersect with the road to Ubar.
"Was what happened in there what I think happened?" I asked.
Ron smiled. "Uh-huh."
A few weeks later, a manila envelope arrived in the mail from JPL. In it was a computer-generated map of Arabia. Two parallel lines, fifty kilometers apart, angled across the peninsula ... the paths of two scheduled space shuttle passes over the Ubar area. A Post-It from Ron said simply,