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Academic Test 2

READING PASSAGE 2 You should spend about 20 minutes on Questions 14–26, which are based on Reading Passage 2 below.

Mars moon probe keeps scientists in the dark 14/11/2011 For every successful mission to Mars, there is at least another which does not reach its goal. In fact, by 2009, 52.4% of missions to Mars had nose-dived, according to Andrew Nusca, editor of the web log ‘Smart Planet’. Although, we are apparently getting better at it, with more recent missions showing a higher rate of success than in earlier decades.

A satellite in Low Earth Orbit (LEO)

In the past few days, however, the improving figures have come dangerously close to suffering a blow. Telescopes all around the world have been trying unsuccessfully to get in touch with a Russian space probe launched with the aim of exploring one of Mars’ moons, Phobos. While the cause of the problem remains a mystery, it is understood that the spacecraft, known as Phobos-Grunt, failed to make two crucial engine firings which should have sent it hurtling towards Mars. This important course change should have occurred within hours of Phobos-Grunt’s reaching Low Earth Orbit (LEO), a height between 160 and 2000 kilometres at which orbital decay* is considerably slower than that at lower orbits, meaning it will continue to circle the Earth for some time. Due to a communications breakdown, the engines failed to fire, leaving the craft stranded in LEO. A Chinese Mars orbiter, Yinghuo-1, is an incidental casualty of the breakdown, having been designed to piggy-back on Phobos-Grunt all the way to Mars. After a successful blast off from Baikonur Cosmodrome, the problem is believed to have arisen between the on-board computer and its star-oriented navigation system, according to Francis Rocard of the French space agency CNES, whose mission it was to supply some of the probe’s instruments. The ground crew have been unable to contact the probe. Often, when a space mission goes astray in this manner, the craft will lose control of its direction and start to tumble through space. At this point, it appears Phobos-Grunt, which is circling in LEO at an altitude of about 200km, has not reached this problematic stage yet, as it has been spotted by several optical telescopes, holding onto a stable trajectory in its orbit of Earth. This is a positive sign for the mission, as it means that the spacecraft is functioning well enough to maintain its orientation without input from its team back home, explains Pascal Lee of the Mars Institute in California. Repeated attempts to contact the probe have been made, with numerous Russian radio dishes sending radio signals to the craft and waiting for a response, however none has yet been received. NASA has indicated it may join the effort to contact Phobos-Grunt, making use of its Deep Space Network of radio dishes, but moving ahead with such an operation may be slow as it is subject to significant red tape in order to schedule time on the network.

© 2011 – A2p2v1.0 – 21/11/2011


Mission controllers are hanging onto hope that the mission can still be salvaged and this indeed remains a possibility, provided the craft can be contacted and re-programmed to perform the course change at an alternative time. It is a race against the clock however, says Lee, as the craft will slowly lose altitude, drawing closer to Earth with every metre it moves through space (the probe is travelling at somewhere around 2,850 kilometres per hour), and will eventually burn up when it reenters the Earth’s atmosphere. Exactly when this would occur is difficult to estimate, but the Russian space agency, ROSCOSMOS, has provided an approximate date of January next year. One of the concerns about Phobos-Grunt’s return to Earth is that of the toxic fuel carried by the craft. Phobos-Grunt contains hydrazine fuel, which could cause health problems for people on the ground – That’s if it survives the fiery re-entry through Earth’s atmosphere and, by unhappy chance, land in a populated area; a highly unlikely possibility, according to independent space experts. In this worstcase scenario, Russia would be liable for any damage caused by hydrazine from the craft’s reaching the ground, says Michael Listner, an attorney and space policy analyst in New Hampshire. Phobos-Grunt’s mission is to approach the Mars moon of Phobos, study it in detail, and collect a sample of its soil to bring back to Earth for study. Not only would this provide researchers with important information about the origin of this mysterious moon, but it may also contain dust from Mars itself, as impacts from asteroids would blast planetary debris upwards. The floating debris could plausibly fall into Phobos’ gravity well and collect on the Martian moon as it orbits the host planet. Prior to the launch of the Russian mission, Pascal Lee stated, “Phobos’s janitorial services have been in operation around Mars for aeons”, providing significant hope for the possibility of some Martian dust returning with Phobos-Grunt – but that’s if it ever gets there. This is not Russia’s first attempt at reaching Phobos. Two probes, Phobos 1 and Phobos 2, were sent in 1988, one failing due to a computer malfunction, while the other was lost to human error; Just days before the mission, software was uploaded to the on-board computer, containing an error which resulted in the craft’s losing its lock on the Sun, explains Dr. Edwin V Bell II of the NASA Goddard Space Flight Center. Consequently, the craft oriented its solar arrays away from the Sun and the batteries simply ran out. orbital decay – the rate at which a satellite loses altitude as it falls towards its host

Questions 14 – 18 Look at the following opinions (14 – 18) and the list of space experts (A – E) below. Match each of the opinions to one of the experts. 14 The nation that launched the probe will be responsible for compensation if toxins fall to Earth. 15 Phobos has been collecting dust from Mars for a very long time. 16 To date, successful missions to Mars have been in the minority. 17 Mars mission failures can result from mechanical problems or mistakes made by ground crew. 18 Some parts of Phobos-Grunt’s internal systems were not communicating with others. List of experts A Michael Listner B Dr. Edwin V. Bell II C Pascal Lee

D Andrew Nusca E Francis Rocard

Continued overleaf…

© 2011 – A2p2v1.0 – 21/11/2011


Questions 19 – 23 Complete each sentence with the correct ending A – G. 19 Following an important engine function, the probe was supposed to 20 If it remains out of reach, it is anticipated that Phobos-Grunt will 21 Despite being offline, the probe has managed to 22 NASA’s involvement could 23 In order to recover the mission, the crew needs to A B C D E F G

leave the probe stuck in LEO. change course. set another time for the engine firings. estimate a re-entry time. continue to orbit the Earth for a period. maintain a steady flight path. be delayed by bureaucracy.

Questions 24 – 26 Label the diagram below. Write NO MORE THAN THREE WORDS from the passage for each answer.

24 .......................... (Objects descend more slowly)

Launch site:

Two 26 .......................... (failed to occur)

25 ..........................

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© 2011 – A2p2v1.0 – 21/11/2011