Launching people into space may make headlines but it does little useful science. So when George Bush redirected Americas space agency, NASA, away from scientific research and towards a manned return to the moon in 2004, many scientists were disappointed. Now the agency has finally offered some small morsels of comfort in the form of four projects that could accompany efforts for a lunar return. The most exciting of these is the plan for a radio telescope that could be placed on the far side of the moon. Such a device would look back at the early universe to the time when large-scale structures such as galaxies and stars formed. A lunar-based radio telescope would be able to detect long wavelengths that cannot be sensed on Earth because they are absorbed by the outermost layers of the planets atmosphere. Moreover by pointing the telescope away from the din of shorter-wavelength radio waves that are used for communication on Earth, astrophysicists would be able to see the early universe in unprecedented detail. Finding alien life might also be possible with such a telescope. It would be able to map the magnetic fields of stars and exoplanets . It is the magnetic field of the Earth that protects its inhabitants from being bombarded by high-energy particles from space that would otherwise leave the planet sterile. Detecting a magnetic field surrounding an Earth-like exoplanet would prove a promising sign for finding extraterrestrial life. The proposal, led by Joseph Lazio, of the Naval Research Laboratory in Washington, DC, is to create an array of three arms arranged in a Y-shape, each of which would be 500 metres long and contain 16 antennae. Each arm would be made of a plastic film that could be rolled out onto the surface of the moon, either by robots or by astronauts. A second project, headed by Michael Collier, of the NASA Goddard Space Flight Centre, would examine how the solar wind a stream of charged particles ejected from the sun interacts with the tenuous lunar atmosphere close to the moons surface. Such bombardment produces low-energy X-rays that would be detected on the surface of the moon. The third and fourth projects are similar both to each other and to earlier ventures dropped on the moon by the Apollo and the Soviet Luna missions in the late 1960s and 1970s. Some 35 years on, reflectors placed on the lunar surface are still used by scientists interested in geophysics and geodesy . Most of the reflectors are clustered close to the lunar equator. The proposals, led by Stephen Merkowitz, also of NASAs Goddard Space Flight Centre, and Douglas Currie, of the University of Maryland, are to sprinkle some more sophisticated versions over more of the moons surface. Such efforts may attract little attention compared with the launch of the space shuttle Endeavour this week. Nevertheless, when NASA argues that putting people into space inspires young people to study science, it is precisely these endeavours that it wishes to encourage. 1.George Bush redirected NASA away from scientific research because_____ he thought scientific research is useless in the long term. he thought launching people into space was not the first priority. he thought NASA should manage its own business. he thought research was not so practical. 2.Which one of the following statements is TURE of the radio telescope? The radio telescope could look back at the structures of galaxies and stars when they were firstly formed. The device would be interfering with shorter-wavelength radio waves used for communication on Earth. The device could protect long wavelength from being absorbed by the outermost layers of the planet s atmosphere. The device could have unique functions mainly because of the position it would be adjusted. 3.The radio telescope might also be useful in searching for extraterrestrial beings in that_____ it could let the astrophysicists examine all the planets in unprecedented detail. it could find out the magnetic field which could protect beings from being attacked by space particles. it could detect any star and exoplanet surrounding the Earth. it could search out the promising sign for finding extraterrestrial life. 4.The word tenuous most probably means_____ slender. dilute. flimsy. thick. 5.The third and fourth projects are different from earlier ventures dropped on the moon in the following aspects except_____ the position of the reflectors remains on the lunar surface. more advanced applications will be adopted for research. the scope of reflectors will be expanded on the lunar equator. more surface of the moon will be covered.
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