The journey began with lift-off on August 27 from Cape Canaveral atop an Atlas Agena-B launch vehicle. During the 109-day trip to the planet, _Mariner_’s on-board instruments sampled the environment of interplanetary space and telemetered information to Earth stations. Ground-based measurements of the Venerian surface temperature were confirmed by the probe to be around 425° C (800° F). _Mariner 2_ detected no measurable magnetic field or radiation belts, indicating that Venus may have a very different history than has Earth. _Mariner 2_ passed out of tracking range on January 4, 1963, when the spacecraft was about 87 million kilometers (54 million miles) from Earth. The probe is presently in orbit around the Sun. The back-up craft on display would have been launched toward Venus if _Mariner 2_ had failed to reach the planet. Prime contractor for _Mariner 2_ was the Jet Propulsion Laboratory, California Institute of Technology. _Mariner 2_ is from the National Aeronautics and Space Administration. [Illustration: 8. Enlarged facsimile of coded _Mariner 2_ tape transmitted December 14, 1962, from the vicinity of Venus. Encircled portions show microwave and infrared coding.] Friendship 7 [Illustration: 9. Close-up of _Friendship 7_ atop Atlas launch vehicle with escape tower.] [Illustration: 10. Launch of America’s first man in orbit on February 20, 1962, from Cape Canaveral, Florida.] On the morning of February 20, 1962, a 29-meter (95-foot) Mercury Atlas launch vehicle rose from Cape Canaveral carrying John H. Glenn, Jr., in his Mercury spacecraft, _Friendship 7_. This was the lift-off for the first U.S.-manned orbital space flight. In slightly more than 5 minutes the Atlas accelerated _Friendship 7_ to its orbital velocity of 28,230 kilometers per hour (17,540 miles per hour). Astronaut Glenn completed three orbits in 4 hours, 55 minutes. From the orbital path, which varied between 160 and 260 kilometers (100 and 160 miles) above Earth, the first American in orbit described the four sunsets he saw and reported that he was able to distinguish a ship’s wake on the ocean below. Mercury spacecraft had been used in two previous manned suborbital flights which proved that it was a safe vehicle for manned space flights. Later orbital Mercury missions demonstrated that man could live and work in space. _Friendship 7_’s flight tested the performance of the pilot in weightless conditions and the interaction of the human pilot with the various automatic systems in the spacecraft. _Friendship 7_ reentered the earth’s atmosphere and splashed into the Atlantic Ocean only 64 kilometers (40 miles) from the planned site. Glenn and _Friendship 7_ were recovered by the U.S.S. _Noa_ near Grand Turk Island in the Bahamas. The Mercury spacecraft consists of a conical pressure section topped by a cylindrical recovery-system section.