Remains of a Rocket; Answers to Correspondents
Byline: JAMES BLACK;CHARLES LEGGE
QUESTION What's left of Apollo 13?
APOLLO 13 was launched on April 11, 1970. It was meant to be Nasa's third Moon landing.
Disaster struck two days and eight hours later, almost 200,000 miles (321,860 km) from Earth, when one of the oxygen tanks in the service module exploded. This knocked out electrical power to the ship and forced mission control to abandon the Moon landing.
The command module systems remained functional but were deactivated so that the spacecraft could still re-enter Earth's atmosphere on its return. The crew endured difficult conditions due to severe constraints on power, cabin heat and drinkable water, but returned successfully.
The only portion of Apollo 13 hardware that remains is the command module - the gumdropshaped capsule that acted as the crew cabin. As with all Apollo missions, successive pieces of the rocket stack were discarded when no longer needed by the mission.
The first two stages of the Saturn V launcher dropped into the Atlantic Ocean when their fuel was spent. The third stage slammed into the Moon's surface, creating 'moonquakes' which could be measured by seismometers left by previous missions (Apollo 11 and Apollo 12).
The service module (the portion of the spacecraft damaged in the explosion) was jettisoned before re- entry and burned up in the Earth's atmosphere.
The lunar module was also jettisoned and burned up in the atmosphere, although a small nuclear reactor (intended for use only on the surface of the moon) survived re-entry. This landed in the Pacific Ocean off the coast of New Zealand.
The remaining portion, the command module, is now in the Kansas Cosmosphere and Space Centre, in Hutchinson, Kansas.
G. Peavy, High Wycombe, Bucks.
Lift off: Disaster struck Apollo 13 two days and eight hours later
QUESTION History holds that Columbus, or possibly the Vikings, discovered America. Weren't the Russians aware of the huge land mass on their eastern border?
IT IS widely accepted that Siberian hunter gatherers crossed into America 12,000 years ago, during the Pleistocene Ice Age.
They could cross between the two continents by the 1,000 mile Bering Land Bridge, which spanned what is now the Bering Strait.
Recent archaeological and genetic evidence shows that these people reached the tip of South America 11,000 years ago. Land animals could also migrate using the bridge. There is archaeological evidence for mammals that evolved in Asia living in North America, such as lions and cheetahs, which evolved into now-extinct North American species.
Camelids that evolved in North America (and later became extinct there) were in turn exported to Asia. It has recently been noted that Amerindian groups in the Arctic exhibit strong DNA relations to Siberian peoples.
However, most modern inhabitants of Russia would not have known of the continent on their eastern border until well after Columbus's discoveries in 1492. …