A Link Between Viking and CLARREO at Langley
By: Jim Hodges
Dick Bender offered a history lesson to members of the Climate Absolute Radiance and Refractivity Observatory team over lunch Tuesday.
Bender worked in Guidance, Navigation and Control with Viking, the gold standard for Langley-run missions in 1976. He was reminded that he was the one who announced to the world that "The Viking Has Landed."
Tuesday's scenario brought forth one overriding question: What does Viking, a mission to land on Mars, have to do with CLARREO, which is destined to – among many things -- put satellites in orbit to measure reflected radiation from Earth, calibrate instruments already measuring climate and provide a climate record so accurate that policies of the future will depend on it?
"Langley stood up a mission management team for Viking," said Steve Sandford, head of Systems Engineering at NASA Langley. "Since then, we've shipped a lot of hardware and supported a lot of missions, but now we're standing up a mission management team again" for CLARREO.
Sandford is head of that team.
"The science is different," he said of Viking, which had at its core determining the possibility of life on Mars; and CLARREO. "But both had decisions to make on space vehicles and on hardware."
Bender presented the kind of anecdotal information about Viking that sometimes gets lost in the shuffle of all of the data that the mission generated, data still in use today.
He offered the Viking logo.
"We put out a call for students to do the logo for Viking," Bender said. "We got 53,000 entries."
The CLARREO team looked impressed.
"Viking was supposed to be an all-American product," Bender said. "To my knowledge it was – except that we were having trouble with the S-band communications. We ended up using a Japanese transistor in it."
He went over the history of Mars efforts by the then-Soviet Union and NASA, showing that, no, Viking wasn't the first craft to land successfully on Mars. Rather, a Soviet craft landed successfully two years earlier, but it went silent forever only 20 seconds into its mission.
"It was the first successful landing, but not the first successful mission," Bender said.
Many of the younger members of the audience tittered when he told them Viking's computer had only 18 kilobytes of memory, tiny by today's standards; and that data could be up-linked at a rate of only four bytes per second, glacially slow now.
"Remember, we had to program the entire landing sequence on 18 kilobytes," he said later. The difficulty of that boggles the imagination of today's computer-wise listener.
"Jim Martin (the program manager) used to have a list of the top 10 problems on the wall, and computers were always on it," Bender said.
And he talked of the excruciating wait. It took 45 minutes to send a signal from Earth to Viking and get a return because the distance between the two. When an image finally arrived, "it was incredibly exciting, I can tell you," Bender said.
He also talked about the first images released to the public. They had a blue sky, as though the pictures were taken in the California desert, rather than the red tinge of Mars. Adjustment to on-board cameras make the color true.
The real lesson, though, is to "be sure and not let people who have worked in space operations get away from you," Bender said.
In his case, Sandford hasn't. More than 30 years after announcing that Viking had landed, Bender works as a contractor in avionics and power for CLARREO.
He offers yet another link between the two.
NASA Langley Research Center
Managing Editor: Jim Hodges
Executive Editor and Responsible NASA Official: H. Keith Henry
Editor and Curator: Denise Lineberry