Excerpts from "the first rough draft of history" as reported in The Washington Post on this date in the 20th century.
Mariner 4 transmitted 21 pictures that covered only one per cent of the planet's surface, but was enough to show that Mars is more like the moon than the earth. Other Mariners surveyed the planet further, and in 1976 the Viking missions landed on its surface. On July 4, 1997, the Mars Pathfinder deposited a tiny robot rover, Sojourner, which sent back the most expansive views and detailed information about the planet to date. This July 4th, the Hubble Space Telescope scanned virtually the entire planet's surface, revealing extraordinary details, like Olympus Mons, a 17-mile high volcano. An excerpt from The Post of July 16, 1965.
Mariner 4 returned its first Mars picture to the earth today and all reports indicated the historic photo will be excellent.
Video signals from spacecraft were good, and shading clearly was evident, according to officials at the Jet Propulsion Laboratory here where the mission is being controlled.
The initial data relayed from the deep space net tracking station at Madrid sparked a wave of confidence at Mariner Control that a full sequence of 20 to 21 closeup pictures will be received during the next ten days.
It also quieted much of the concern that arose during Mariner's photo pass across Mars Wednesday when two irregular signals indicated that a tape recorder on the spacecraft had malfunctioned.
As the first picture was being received by relay at the Jet Lab, scientists who conducted the several experiments aboard Mariner reported:
* The magnetic field of Mars is but one-thousandth that of earth -- essentially no magnetic field at all.
* The planet apparently has no radiation band similar to the earth's Van Allen Belt.
* There is no evidence of a belt or unusual concentration of cosmic dust around the planet.
* There was no significant evidence of a shock wave around Mars caused by solar wind flowing across the planet.
In discussing the signals that caused concern during Wednesday's pass, John Casani, spacecraft systems manager, said these irregular transmissions -- indicating the premature end of photo recording -- apparently were false.
This could not be determined with certainty, however, until tracking stations begin to receive Mariner's second picture, Casani said.
If the spacecraft's transmission of a second photo began on schedule -- about two hours after the first picture was completed -- the irregular signals probably can be classified as spurious, he added.
This series is available at www.washingtonpost.com