|
|
|
|
|
Lunar surface charging: A hazard for astronauts? ROYAL ASTRONOMICAL SOCIETY NEWS RELEASE Posted: April 16, 2007 For four days every month the Moon passes through the magnetic field of the Earth and parts of the lunar surface are charged with static electricity. Dr Mike Hapgood of the Rutherford Appleton Laboratory will present a model at the Royal Astronomical Society National Astronomy Meeting in Preston, which suggests that this charging may increase after the year 2012 and become an important issue for future lunar explorers. Once in every orbit around the Earth the Moon moves through the magnetic tail - the region on the nightside of the Earth where the magnetic field is drawn out into a million or more kilometre long tail pointing away from the Sun. In the middle of the tail there is a region full of energetic electrons and other charged particles (the plasmasheet). When the Moon passes through the plasmasheet these electrons can collect on parts of the lunar surface and charge them with static electricity. Observations from NASA's Lunar Prospector spacecraft during 1998 confirm the existence of this charging. Dr Hapgood's model suggests that the exposure of the Moon to plasmasheet charging varies markedly over an 18-year cycle linked to changes in the Moon's orbit. This exposure was low at the time of the Apollo landings in the early 1970s and is low again today - but it was high in the 1990s and will rise again after 2012. The United States, Russia, India, Japan and China have all announced plans to send astronauts back to the Moon around the year 2020 - at the time when lunar surface charging is predicted to be high. Lunar surface charging may be an important issue for future lunar exploration because it increases the risk of electric discharges, which can interfere with and damage sensitive electronics. It may also affect the behaviour of lunar dust, which is a recognised hazard for lunar astronauts as it can easily enter spacesuits, living quarters and equipment. Dr Hapgood comments, "Electrical charging is one of the less well-known natural hazards of spaceflight. It's important to understand it how this affects the Moon so spacecraft designers can use scientific knowledge to protect future explorers." |
|
|
|
|||||||||||||||||||||
The Russian Soyuz spacecraft with Expedition 15 cosmonauts Fyodor Yurchikhin and Oleg Kotov, along with tourist Charles Simonyi, fly to the space station following launch from Baikonur Cosmodrome.
One of the most daunting yet crucial human spaceflights occurred in December 1993 as the crew of shuttle Endeavour embarked on a mission to repair the Hubble Space Telescope. The observatory had been launched three-and-a-half years earlier with a crippling vision flaw. Two teams of spacewalkers carried out five EVAs to install corrective optics and other equipment to fix the telescope's problems. The astronauts take you through the mission in this post-flight film.
This documentary looks back at Apollo 7, the first manned flight of the Apollo program. Apollo 7 was designated as the essential engineering test of the spacecraft before the ambitious lunar missions could be attempted.
NASA astronaut Suni Williams will run the Boston Marathon on a treadmill aboard the International Space Station. To preview the event, Williams, an accomplished marathoner, and Expedition 14 commander Michael Lopez-Alegria talk with The Boston Globe and the
New England Sports Network.