National Geographic : 1963 May
JET PROPULSIONLABORATORY AOQ DXQ XZAIZXAZZKZZD X; QKZZ ' LKADRKHQ ZSQSG: S Z QSGI GGXRS DXQ ZOQ ZAIZAZ QKS X ZQKVA XXDRDZDRAN QSA Z DSQSAQGGGGXRSNZOK DNQ ZOK DNQ XZAIZGAVQQKZG X Cryptogram From Space Tells Venus's Secrets in Coded Letters Shakespeare's "full star that ushers in the even" hides beneath a blanket of clouds im penetrable to the strongest telescopes. Mariner (right) scanned sun rays modified and reflected by Venus and sent back a stream of coded information. Men and computers translated these seemingly meaningless letters. "QSGI" presents a microwave report on wa ter presence and surface temperatures (later found to be 800° F.). "QQKS" gives infrared data on cloud cover (continuous, 15 to 20 miles thick) and cloud temperature (from 2000 F. to minus 60° F.). Sensors detected no magnetic field and no Van Allen belt of trapped radiation. Passing Venus, Mariner communicated with earth to a distance of 53.9 million miles, using only three watts of power. This means that ra dio contact is probably possible throughout the solar system, a finding vital to manned flight. All this time, Mariner was telling earth about the unprobed areas it was voyaging. It discovered that throughout these regions the number of cosmic rays-energetic particles believed to originate outside our solar system -is constant. On the other hand, waves of high-energy sun particles, produced by solar flares, came at irregular intervals. Those de tected by Mariner, however, were determined to be no hazard to the men who will one day sail the far reaches of this new ocean. Mariner also confirmed the existence of a constant "solar wind." Made up of electrons and fragments of hydrogen and helium atoms, this energy stream rages from the sun at 200 miles a second when the sun is relatively quiet, with gusts up to 500 miles a second. No Magnetic "Holes" in Space Further, Mariner's magnetometer was al most constantly busy, reporting space to be filled everywhere by a faint magnetic field. Only two bits of cosmic dust were detected along the way, indicating that these specks of matter are only one ten-thousandth as plentiful as those found near our planet-a 740 reassuring finding for spacecraft designers. And, as it sped onward, the craft was giv ing scientists data that should provide the most accurate estimate yet of the mean dis tance from earth to sun. This so-called astro nomical unit-nearly 93 million miles-is the vital measuring stick of our solar system. For a month Mariner cruised without inci dent, its electronic brain sampling each in strument in turn and relaying its coded find ings to earth. Suddenly on October 31, the electric power aboard dropped alarmingly. In charge at the Jet Propulsion Laboratory control room in Pasadena was Space Flight Test Director Tom Bilbo. His desk, one of three so equipped, held three television consoles showing raw data as it came in. On a board nearby, assist ants posted decoded information. These num bers left no doubt; the craft was in trouble. Bilbo called Jack James, who happened to be in Tucson, Arizona. For several hours on the telephone they discussed the possibilities. It appeared that one solar panel might have shorted out. They decided to turn off the four instruments to conserve Mariner's power.