Evidence of Black Holes Discovered by Jury-Rigged Shuttle Telescopes : Space: Ground control bypasses failed computers on orbiter. Columbia crew gives lessons to students via television link.
Scientists on Friday bypassed two faulty computers aboard the space shuttle Columbia that had jeopardized a historic astronomy mission. They also reported major discoveries, including stunning evidence that black holes lurk at the hearts of active galaxies.
The failure of a second computer Thursday left the crew unable to control telescopes aboard the shuttle, and scientists feared they were not going to get the results they had hoped for from the long-awaited Astro astronomy mission.
But, employing somewhat crude techniques, several hundred people on the ground in Texas and Alabama teamed up with orbiting astronomers to turn the tide in favor of science.
The telescopes are now being guided from the ground and then fine-tuned by the astronauts, and elated scientists said Friday that they were getting better data than they had dreamed possible just hours earlier.
“I didn’t want to go in this morning,” said astronomer Morton Roberts, “but, when I got there, everybody was ecstatic.”
The new process takes more time than the automatic computer-driven system that was supposed to point the telescopes and keep them locked on the targets, so scientists will not be able to look at as many objects as they had hoped. But they will look intensely at the things they do focus on.
Both computers shut down after they overheated, leaving the crew with no way to give the telescopes the precise commands needed to point them at the right targets. So that function was taken over by Mission Control at the Marshall Space Flight Center here. Then, the astronomers aboard the shuttle used a joy stick, which resembles a control panel for a video game, to nudge the telescopes into exactly the right position and keep them locked on target.
No one was sure it would work, but, by most measurements, it did so quite well.
The astronauts took time out from their work Friday to finally realize the late Christa McAuliffe’s dream: teaching a lesson from orbit, explaining the wonders of astronomy and urging schoolchildren to study math and science.
The lessons from space were beamed down to televisions in classrooms across the nation in a project to show students how astronauts live and work in orbit and to describe the value of studying the entire electromagnetic spectrum to learn more about the structure and evolution of the cosmos.
“I’m talking to you from the space shuttle Columbia orbiting 200 miles above the surface of the Earth,” astronomer Samuel Durrance said as he began the space lesson from Columbia. “I’d like to talk to you today about space, astronomy and the electromagnetic spectrum.”
In addition, select groups of seventh- and eighth-graders were gathered at the Marshall Space Flight Center here and the Goddard Space Flight Center in Greenbelt, Md., to observe the lesson.
By using satellite dishes, students across the nation were able to watch the lesson live in their classrooms in an unprecedented effort to highlight science education.
The 20-minute lesson, entitled “Space Classroom: Assignment the Stars,” was taught by Durrance and astronaut Jeffrey Hoffman, who took their students on a brief tour of the shuttle. Questions from the students were answered by astronaut Robert Parker and astronomer Ronald Parise.
“If you are interested in this sort of work and would like to learn something about it yourself and perhaps participate in the Space Age in the future, my recommendation for all of you students listening is to continue to study hard . . . read a lot about astronomy and space, and maybe you can help answer some of these questions that we’ve been talking about,” Hoffman said.
Friday’s space lesson took place nearly five years after the Jan. 28, 1986, explosion of the shuttle Challenger that killed all seven aboard, including McAuliffe, a New Hampshire schoolteacher.
Willie Carter, an eighth-grader from Memphis, Tenn., said the country “is sort of regaining from the Challenger explosion. This has probably put more hope in all of us. I feel better now that we’ve got something going compared to the explosion.”
The Astro observatory aboard the Columbia consists of four telescopes that study ultraviolet light and X-rays, which cannot penetrate Earth’s atmosphere.
The four telescopes, each with different strengths, allow scientists to study objects simultaneously, but in different ways. Meanwhile, other teams are studying the same objects from ground-based observatories. All that data will eventually be compiled, giving scientists a more comprehensive view of the universe.
Two of the telescopes found strong evidence that mysterious objects known as black holes do exist, although no one will ever be able to see them.
Theorists have long held that black holes power galaxies that emit copious amounts of radiation, so-called active galaxies, and there has been some evidence to support that. Black holes are thought to be so dense that a spoonful would weigh as much as Earth, and their gravity is so great that even light cannot escape.
A black hole should have a powerful impact on its neighbors, ripping nearby stars apart and pulling in the debris like a giant whirlpool in space.
Scientists are concentrating on finding features in the disks of material swirling around objects believed to be black holes. The disks should emit such things as X-rays created in the violent destruction of material as it is swept toward the black hole.
Astro’s Broad Band X-Ray Telescope was trained on one galaxy, called Markarian 335, that is thought to be harboring a black hole. The result, said astronomer Peter Serlemitsos, the instrument’s principal investigator, “tells us that indeed there are likely to be giant black holes,” because the sensitive instrument found exactly what theorists had predicted it would find if the galaxy has a black hole at its center.
This telescope does not produce pictures. Instead, it produces a “spectrum” that shows the characteristics of the light emitted by the target. Light, for example, discloses the chemicals present when the light was produced.
The X-ray telescope also measures the level at which X-rays are being produced by the target, and, according to theory, that level should rise enormously near a black hole because more material is being ripped apart in the violent process.
And, in a dramatic announcement Friday, Serlemitsos said the data collected by his instrument amounted to “undisputed evidence that this upturn does indeed take place.”
Farther out from the region where the X-rays are being produced, the swirling gas and dust around a black hole should emit ultraviolet light. And another instrument aboard Columbia, the Hopkins Ultraviolet Telescope, found that to be the case.
“He sees the hottest stuff,” said Arthur F. Davidsen, principal investigator on the Hopkins telescope, referring to the region that produces Serlemitsos’ X-rays. “I see the stuff that’s on its way.”
Davidsen said data collected by his telescope fits nicely with the X-ray evidence, with one picking up where the other leaves off.
“We’re going to pull them together, and bingo!” Davidsen said.
Will that prove that black holes exist?
“I doubt that anybody will ever come up with absolute proof,” Serlemitsos said. “Instead, you will have an accumulation of evidence” that is very convincing.
So, although nobody will ever “see” a black hole, two telescopes aboard Columbia searched a closer part of the neighborhood than anyone has been able to visit before. Davidsen stopped short of claiming total success for his own experiment, but he said of Serlemitsos’:
“His data looks fantastic to me.”
