The Moon Guide
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The phase of the Moon right now

Phase

spacer Lunar Exploration
<The first explorers

Landers and orbiters

After these early excursions, the race was on to obtain the first views from the lunar surface itself. Another Soviet probe, Luna 9, achieved this in February 1966, when it descended onto the western Oceanus Procellarum, the largest of
Luna 9; Galaxy Picture Library
Luna 9
the Moon’s dark lowlands. Over the next three days Luna 9 took panoramas of its surroundings, showing a scattering of rocks and the rim of a nearby crater. Luna 9’s signals were monitored by the giant radio telescope at Jodrell Bank, which released the first picture before the Russians. Unfortunately,the horizontal scale was too compressed and gave the surface an unrealistically jagged appearance.

Luna 9’s landing system was only rudimentary – the craft was a reinforced sphere ejected from the carrier probe shortly before impact, and it dropped onto the surface at car-crash speed. A more advanced system, using braking rockets that provided a genuine soft-landing similar to that intended for manned landings, was employed by the US Surveyor series, the first of which touched down four months after Luna 9, also in Oceanus Procellarum. Surveyor 1’s successful landing finally dispelled fears that the surface was covered in deep drifts of dust that might swallow a crew of astronauts.

Even so, the surface was not bare rock, but a compacted soil known as the regolith, built up over aeons by meteorite impacts. The regolith covering the maria is now known to be about 5 m deep, thickening to two or three times that in the highlands.

Surveyor 3 (Galaxy Picture Library)
Surveyor 3 on the Moon
Out of seven attempted Surveyor landings five were successful, and confirmed that the Moon was perfectly safe for humans to land and walk on. Each Surveyor carried a TV camera to photograph its surroundings. Three of them carried a soil analyser which found the composition of the maria to be similar to that of volcanic basalt on Earth, and two of them were equipped with a mechanical arm to dig in the soil.

At the same time as the Surveyor landers were providing an astronaut’s-eye view of the surface, a series of Lunar Orbiter photo-reconnaissance probes was scanning the Moon from orbit. Each Lunar Orbiter carried two cameras, one for close-ups and the other for wide-angle views. The photographs were recorded on film that was processed aboard the spacecraft and the pictures were transmitted to Earth in strips, which accounts for their banded appearance. Tracking the Lunar Orbiters revealed the existence of mascons (short for mass concentrations), areas of denser rock and hence increased gravitational pull, under the lunar maria.

The first three Lunar Orbiters concentrated on possible Apollo landing sites, but Lunar Orbiter 4 was placed into a near-polar orbit from which it mapped almost the entire Moon, front and back, in unprecedented detail. Lunar Orbiter 5, the last of the series, filled in missing areas on the far side and scrutinized sites of special interest, such as the bright ray craters Tycho and Aristarchus. The Lunar Orbiter images remain our best overall survey of the Moon to date, and can be seen in the Lunar Orbiter Photographic Atlas of the Moon.

During this time the Soviet Union was also launching orbiters – Luna 10, Luna 11, Luna 12 and Luna 14 – and followed up the Luna 9 landing with Luna 13, but these achievements paled beside the American successes. More significant were the flights Zond 5 and Zond 6 in 1968, which looped behind the Moon and returned to Earth carrying biological samples; Zond 5 even carried a dummy cosmonaut. These probes, actually modified versions of the Soyuz manned spacecraft, were clear evidence that the Soviet Union was preparing for manned lunar missions.


                                                                      Sample returns and lunar rovers  >

spacer Aldrin on the lunar surface

The first explorers

Landers and orbiters

Sample returns and lunar rovers

Map of lunar landings

Timeline 1

Apollo To The Moon!

Apollo's Chariots

Meeting The Challenge

Repeating The Feat

Driving on the Moon

Heading for the Hills

Apollo landing chronology

 
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