MARS INVASION: EXPLORING THE RED PLANET Introduction

Transcription

1 MARS INVASION: EXPLORING THE RED PLANET Introduction Focus Many scientists believe that Mars may contain the answers to one of the most tantalizing questions for human beings: Is there life on other worlds? This News in Review module focuses on past, present, and future investigations of the Red Planet, and the prospect for robotic and human visits. Did you know... The first exploration ship called the Beagle was a naval vessel that carried Charles Darwin on the global sea voyage ( ) that led to his theory of evolution? YV Sections marked with this symbol indicate content suitable for younger viewers. As an item of popular interest, the exploration of space seems to fade in and out of our consciousness. The first satellite launchings, the first humans in earth orbit, the first humans on the moon these firsts always cause a flurry of interest in space research. As the firsts fade from memory, however, so does much of our interest. Space becomes routine; we are aware that satellites are being launched, probes are moving toward their targets, and a space station is already partially constructed and inhabited. But it still takes a major event especially a disaster, like the loss of a space shuttle to remind us of the many and wide-ranging efforts taking place to unlock the secrets of the universe in which we live. It was 1972 the last time a human being walked on the moon. Since then, human space flight has taken place only in Earth orbit. The Chinese have recently placed their first astronaut in orbit. Both the United States and former Soviet Union launched and maintained a series of space stations. Now under construction is the International Space Station, involving technical expertise from 16 nations: the U.S., Canada, Japan, Russia, Brazil, and 11 nations of the European Space Agency. In response to this focus, the U.S. has concentrated its efforts in astronaut spacecraft design on the shuttle program, producing a craft suitable for use only in Earth orbit. It was to be a cheap and reliable method of serving the space stations and orbiting science platforms like the Hubble telescope, as well as an effective way of launching research satellites. The shuttle proved to be neither cheap nor reliable. Each mission cost $500-million to launch, and the shuttles required lengthy and extensive servicing before each reuse. The program did not capture popular imagination, and NASA (National Aeronautical and Space Administration) saw this reflected in the size of its budget. It took a major disaster like the loss of Columbia for most people to even realize a mission was underway. Oddly enough, the success of two robotic missions may have rekindled real interest in the future of human space flight. There is no doubt that the successful landing on Mars of the rovers Spirit and Opportunity has captured world attention. The key to this interest lies in the fundamental question they are trying to answer: Is there or was there ever life on Mars? Colin Pillinger, the British scientist who led the team behind the European Space Agency s lander Beagle 2 (which failed to transmit after being sent to the planet s surface), says that finding life on Mars might be the biggest scientific triumph ever. There cannot be a human in the world who has not looked at the stars in the night sky and thought, Are we alone? Some say it [finding life on Mars] would be like the moment in the 16th century when Copernicus discovered that we revolved around the sun, not the sun round us. But I think this will be bigger (Time International, January 13, 2004). Planetary scientist Jim Bell summed up the importance of the search for Martian life. Mars is on NASA s short list of places to examine closely for evidence of life past or present. If the planet was Earthlike early in its history CBC News in Review March 2004 Page 46

2 and if life developed there, it would provide support for those who believe that life is ubiquitous in the universe. If conditions were favourable but life failed to develop, then it would lend ammunition to those who think that terrestrial life is a rare or once-in-auniverse quirk (Mercury, January 7, 2003). There are few scientists who believe that Spirit and Opportunity will be able to give a final answer to this search for life. Nonetheless, the two rovers thanks to the Internet have become the eyes for millions of Earthlings who are exploring this alien world by visiting NASA s Web site (mars.jpl.nasa.gov). Our renewed fascination with other worlds is likely partly responsible for the timing of U.S. President George W. Bush s announcement of a new human space flight program for that country. While no precise date is given for a human flight to Mars, the main components of the program point to such an event. These include the development of a new spacecraft. The Crew Exploration Vehicle is capable of flight beyond Earth orbit and even beyond the moon. Of equal importance is the establishment of a permanent moon base, capable of being used as a launching pad for further exploration. The problems to be resolved before a human mission to Mars could take place are extensive (and expensive). Some of these are basic: equipping an expedition that would take at least six months in both directions with the necessities of life. Others are more troubling, such as finding a way to shield the crew from the intense radiation that could destroy every cell in their bodies. Meanwhile, further robotic missions to Mars some with Canadian participation are in the planning stages. Even if NASA proceeds quickly with its plans for human space flight, the robotic missions will almost certainly continue. Mars may not easily give up its secrets, but Earthlings are determined to see that it eventually does. For Reflection/Discussion Writing about NASA, critic Anne Applebaum (The Washington Post, January 7, 2004) said: Their most dangerous missions the ones involving human beings produce the fewest research results, yet receive the most attention, applause, and funding. Their most productive missions the ones involving robots inspire interest largely because the public illogically believes they will lead to more human space travel. Is Applebaum right? Do we believe the only really valuable space travel involves human beings? Should we be focusing on the work that can better be done by machines? CBC News in Review March 2004 Page 47

3 YV MARS INVASION: EXPLORING THE RED PLANET Video Review Before Viewing Complete a simple collage of at least 10 words that reflect your understanding of the planet Mars. During the Viewing While viewing the film, add at least 10 more words that accurately describe Mars and its exploration. After the Viewing Now, working with a partner, outline your views on the challenges and opportunities presented by the exploration of Mars. Use this organizer to record your ideas. Challenges Opportunities CBC News in Review March 2004 Page 48

4 YV MARS INVASION: EXPLORING THE RED PLANET A History of Mystery Did you know... In 1938, Orson Welles caused a panic in the United States with his radio adaptation of War of the Worlds? Tim Burton s 1996 film Mars Attacks is a hilarious adaptation of the War of the Worlds Martian invasion prototype? Mars has been a source of great mystery ever since scientists began a serious study of the planet. Giovanni Schiaperelli, the Italian astronomer who published the first map of Mars (1877), was convinced that he was observing a pattern of lines crisscrossing the surface. He called these canali (channels). Enter Percival Lowell, wealthy U.S. amateur astronomer. Lowell mistranslated canali as canals, and declared that this was obviously a network for irrigation and proof positive that Mars was inhabited by intelligent beings. The canali were ultimately revealed to be no more than an optical illusion. They had, however, provided grounds for the popular belief that there just might be an intelligent race of Martians. In 1898, H.G. Wells published War of the Worlds, one of the first books to present a race of alien beings attempting to dominate Earth and those beings were Martians. Earth Attacks Even non-superstitious scientists have been known to speak of the curse of the Red Planet. Since 1960, a total of 34 missions have been launched to study the planet Mars. Of these, only 13 can be considered successes (and, in some cases, partial successes). Three of these reached Mars in December 2003 and January The following is a list of the successful missions and their results, based on data from the NASA Jet Propulsion Laboratory and other sources: Launch Mission Country Purpose Results Date Name 28/11/64 Mariner 4 U.S. Mars flyby returned 21 photos 24/2/69 Mariner 6 U.S. Mars flyby returned 75 photos 27/3/69 Mariner 7 U.S. Mars flyby returned 126 photos 30/5/71 Mariner 9 U.S. Mars orbiter returned photos 25/7/73 Mars 5 U.S.S.R. Mars orbiter lasted a few days 20/8/75 Viking 1 U.S. Mars orbiter/lander with Viking 2, returned photos 9/9/75 Viking 2 U.S. Mars orbiter/lander see Viking 1 7/11/96 Mars Global U.S. Mars orbiter high-detail mapping through Surveyor January 2000; 2 nd mapping mission continues 4/12/96 Mars U.S Mars lander and rover landed 4/7/97, last transmission 27/9/27 Pathfinder (Sojourner) 7/3/01 Mars Odyssey U.S. Mars orbiter studying global composition, ground ice, thermal imaging 2/6/03 Mars Express/ Eur. Space Mars orbiter/lander lander lost, orbiter is Beagle 2 Agency studying Martian geology 5/6/03 Mars Exploration U.S. Mars lander studying geology at Gusev Crater Project A/Spirit 25/6/03 Mars Exploration U.S. Mars lander studying geology at Meridiani Planum Project B/ Opportunity CBC News in Review March 2004 Page 49

5 Did you know... The first successful landing on Mars was by the U.S.S.R. s Mars 3, on May 28, 1971? The lander operated only 20 seconds before failing, and returned no useful data. Future Mars Visits Visits to Mars have been planned through NASA will be sponsoring four of these: 1. The Mars Reconnaissance Orbiter in 2005 will, through high-resolution photography, provide detailed information about thousands of sites on the planet. Its cameras will have the resolution to show rocks the size of a desk. The satellite will use radar to look for water and other geologic layers hundreds of metres below the surface. 2. The Phoenix Mars Scout will land in northern Mars to analyze the soil in this ice-rich area and explore the possibility of past or future life. 3. The Mars Science Laboratory will be launched in 2009 with the capability of exploring a large area of the planet for a year or more. (Further information on Phoenix and the Mars Science Laboratory is available in Canadian Connections on page 53 of this guide.) 4. Also in 2009, the Mars Telecommunications Orbiter will be sent to the planet to provide better communications for current and future Mars missions. Discussion 1. The possibility of a human mission to Mars is many years in the future. If the current and future robotic missions (including a possible future mission to return samples of Martian rocks and soil to Earth) fail to find evidence that Mars ever supported life, how is this likely to affect the potential for human exploration of the planet? 2. Would you ever consider being an astronaut on a mission to Mars? Explain fully. CBC News in Review March 2004 Page 50

6 MARS INVASION: EXPLORING THE RED PLANET The Earthlings Are Coming Did you know... Spirit and Opportunity were named by Sofi Collis, a nineyear-old from Scottsdale, Arizona, who won an essay contest? Collis, who was adopted at age two from a Siberian orphanage, said that the landers journey reminded her of her own from Russia to the United States which gave her both spirit and opportunity. Further Research Visit the European Space Agency to learn more about Mars Express at export/esami/ Mars_Express/ index.html. It was the most spectacular convergence in the history of space exploration. Four different missions were headed for Mars from Earth, and three of them were destined for landings on the planet s surface. Nozomi One of these, a Japanese probe named Nozomi, had been launched in July 1998, and intended to enter Mars orbit in Technical problems prevented this, and it was placed in temporary solar orbit until it could be redirected for a 2003 arrival. Unfortunately, solar flares damaged its electrical system, and it was necessary to redirect it out into space. Mars Express and Beagle 2 Next to launch was Mars Express, from the European Space Agency. It had a dual mission: to explore from orbit the geological and topographical features of Mars, and to land Beagle 2, a suitcasesized probe that had been built for only $60-million raised from both public and private sources. Beagle s mission: to search for direct signs of life using mass spectrometry. It was designed to analyze the isotopes of any carbon it might find. Beagle 2 was the second victim of what some call the curse of the Red Planet. Sent to the surface on Christmas Day 2003, it failed to communicate with scientists after landing. However, Express itself successfully entered orbit, and soon transmitted the best evidence ever that water does exist as ice on the planet. Using infrared photography Express was able to detect water molecules vaporizing from the planet s South Pole. Many scientists believe that Mars once had surface water, and could have supported life. Express s early surveys seem to reinforce this belief although project scientists stress that it is much too early to draw conclusions. Express will continue its geological, topographical, and atmospheric surveys of Mars for at least one Martian year (687 Earth days). Spirit and Opportunity NASA made a double contribution to the Mars exploration season with two separate missions making up the Mars Exploration Project (MEP). First to land was Spirit, on January 3, 2004; Opportunity landed January 24. Each rover is the size of a small golf cart and weighs about 185 kilograms. They arrived on Mars in a spectacular fashion: entering Martian atmosphere on a bullet-like trajectory, then descending by parachute until 20 metres from the surface. Finally, wrapped in airbags, they dropped and bounced across the surface for up to two kilometres. Two rovers were sent to take advantage of the close alignment of Earth and Mars, and to reduce the risk that an entire mission might be lost. For a while, it seemed that MEP might also be subject to the curse. Spirit deployed successfully and sent back stunning images of its surroundings; suddenly it stopped communicating. Fortunately, mission specialists quickly determined that Spirit s problem was in its flash memory, a problem that caused it to repeatedly try to reboot itself. They solved the problem by deleting hundreds of unnecessary files. CBC News in Review March 2004 Page 51

7 Did you know... For humans to exist on Mars they will need about 20 litres of water each day in order to survive? They must find or produce this water on Mars itself. Further Research Follow the adventures of Spirit and Opportunity at mars.jpl.nasa.gov. Update After studying data from the Mars rover Opportunity, NASA scientists declared that it was likely that Mars was once soaked with water.they cautiously noted that while the conditions for life existed, it was not neccessarily true that life had actually existed on Mars. Basically, Spirit and Opportunity are at work trying to read the history of Mars climate. Unlike Beagle 2, their mission is not a direct search for life; instead, they examine minerals that might suggest that water existed in the past and could have harboured life. Both rovers exploration sites were chosen as relatively safe landing areas where water might once have flowed. Spirit s landing site is called Gustav Crater, which was chosen because it may have been an ancient lake. It is hoped that Spirit s research might indicate whether water did pond there. Opportunity landed on the other side of the planet at Meridiani Planum. This area is known to contain a large amount of one form of hematite (an iron ore). On earth, this form of hematite was usually created from sediments laid down in water possibly from a hot spring. Both rovers carry nine cameras, and are capable of taking pictures ranging from panoramas of their surroundings to microscopic close-ups of any rocks they sample. Each has a deployable arm with a small drilling and grinding device, two spectrometers, and the microscopic imager. On each rover s mast is a thermal infrared spectrometer that is used to deduce the mineralogy of rocks and soils in the area, and help in the selection of which rocks to study. Each of the rovers is expected to explore its landing site for about three months before dust settling on its solar panels and recycling limitations on its batteries force it to shut down due to a loss of power. The maximum either rover will travel in one day is 100 metres. A set of commands is sent every morning with full instructions on what each rover is to do that day. As a result, it can take days to have a rover perform an action that a human could manage in a few seconds. Scientists are counting on Spirit and Opportunity to analyze only six or so rocks each during the entire mission. Discussion A single shuttle launch costs $500-million. The current estimated cost of the International Space Station is $32-billion. The total cost of Mars Express (including Beagle 2) was $300-million. The two rover missions cost about $400-million apiece. How would you assess the cost-effectiveness of each of these items as part of a nation s space exploration budget? CBC News in Review March 2004 Page 52

8 MARS INVASION: EXPLORING THE RED PLANET Canadian Connections Quote Humans will go to Mars because humans wish us to go. Marc Garneau head of Canadian Space Agency, Toronto Star, February 9, 2004 Canadian scientists, engineers, and astronauts have been part of the exploration of space for many years. The country s most public contributions have been to the shuttle program, with eight Canadians six men and two women having flown on a variety of missions since its beginning. A prominent feature of that program has been the robotic Canadarm. One version of the Canadarm has flown with many of the shuttle missions, and has been used, among other things, to launch and retrieve a variety of satellites. A second version is critical to the successful completion of the International Space Station. Canada has also launched a sophisticated series of satellites into earth orbit. Canada is especially renowned in the field of communications satellites, and Canadian companies participate in the design and construction of such satellites world-wide. Another area of special interest for Canadians has been the provision of high-quality imaging from space. RADARSAT-2, to be launched in 2005, will be the most spectacular demonstration of this technology. Many Canadians would be surprised to learn that there is also an important Canadian presence right now on Mars. Both NASA rovers, Spirit and Opportunity, have cameras that are equipped with image sensor chips manufactured by a DALSA Corporation production facility in Bromont, Quebec (DALSA is a Canada-based producer of semiconductors and digital imaging components). These chips are critical in providing high-resolution colour imaging from the rovers panoramic cameras. They are also an essential part of the rovers guidance and navigation system. Canada also had an important piece of equipment on the ill-fated Japanese orbiter Nozomi, which was launched in July 1998 and expected to enter Mars orbit in It was carrying the first Canadian scientific instrument to travel beyond Earth orbit: a thermal plasma analyzer, designed and built in Canada. It would have studied the Martian atmosphere, seeking information on the transformation of the planet over millions of years. Technical problems and damage by solar flares forced the redirection of the probe into deep space. Canada and Future Missions to Mars The next Mars mission by NASA will be part of what it calls its faster, cheaper, better plan of solar-system exploration. Called a Scout mission, it is an attempt to cut bureaucracy and place more of the mission control in the hands of the scientists, to maximize the scientific return. The first Scout mission will be called Phoenix, launched in 2007, with a scheduled landing in the summer of The main purpose of Phoenix will be to study the history of water on Mars and the possibility that living organisms could have survived there in the past or present. Part of the instrumentation on the lander will be a Canadian meteorological station (MET), which will consist of six instrument packages. Using laser radar technology (lidar), MET will conduct a series of climate studies that will detect and measure a number of different elements in the Martian atmosphere. CBC News in Review March 2004 Page 53

9 Further Research Read more about the three Canadian projects for the Mars Science Laboratory at background/space/ mars_canada.html. In 2009 NASA plans to launch a major robotic mission to Mars with the Mars Science Laboratory, which will be nuclear powered and functional for at least two years. (Spirit and Opportunity are expected to be operational for about 90 days.) It has asked Canada, through the Canadian Space Agency, to provide as many as three of the most important components of the mission. These would include: A lidar device, developed by Optech Incorporated, to be used by Phoenix, which would direct the rover to a safe and precise landing A Canadrill, developed by Sudbury, Ontario s Northern Centre for Advanced Technology that will be able to drill two metres into the surface of Mars (much deeper than any device previously developed for drilling operations in space) A rover arm based on the principles used in constructing the Canadarm, which would guarantee the effective operation of the Canadrill and its ability to reach any designated targets Funding for these projects, however, has yet to be approved by the federal government; no such funding was part of the 2003 federal budget. Until funding becomes available through the Canadian Space Agency, Canadian participation will remain in jeopardy. A group of Canadian scientists, working in conjunction with a U.S. team, is proposing that NASA sponsor another mission in Marvel the Mars Volcanic Emission and Life Scout lost out to Phoenix for the 2007 Scout mission, but remains a strong contender for (A decision will be made in mid-2005.) It would be the first mission to fully survey the atmosphere of Mars, taking its observations from a space orbiter. If Marvel goes ahead, it will carry one entirely Canadian instrument that will detect cloud and aerosol layers in the Martian atmosphere. Two of the other instruments will use Canadian hardware and core technology. The mission will also continue the search for any signs of life on Mars, looking for emissions of any bacteriaproduced telltale gasses, such as methane. Team leader Mark Allen of NASA emphasizes the sophistication of the instruments the mission will carry (Toronto Star, February 1, 2004): If you had just three cows anywhere on Mars, we d be able to detect that amount of methane added to the atmosphere. Discussion 1. Is it important that Canada continue to participate in space exploration missions, including those to Mars? 2. Are there specific benefits to either the public or private sectors from such research? 3. How should such research be funded? CBC News in Review March 2004 Page 54

10 MARS INVASION: EXPLORING THE RED PLANET Earthlings on Mars? Quote We may discover resources on the moon or Mars that will boggle the imagination, that will test our limits to dream. We do not know where this journey will end, yet we know this: Human beings are headed into the cosmos. U.S. President George W. Bush (The Washington Post, January 15, 2004) It seems a given that future robotic missions will seek to force Mars to give up its secrets. Certainly, recent successes by Spirit and Opportunity have thrilled not only scientists and engineers, but a large part of the general public. NASA reported that, after Spirit landed successfully, its Mars Web site (mars.jpl.nasa.gov) received 1.45 billion hits over five days. But what of that great dream of science-fiction writers, a human voyage to Mars? How likely are we to see such an event in the near future? On January 14, 2004, George W. Bush announced a new strategic plan for NASA, the organization that oversees all U.S. space flight. While NASA was basking in the public adulation that came from its successful Mars mission, it has also been dealing with the fallout from and damage to its human space-flight program after the loss of the shuttle Columbia on February 1, Bush announced that the U.S. was backing human space flight in a big way. The key components of his new program include: NASA will begin testing a new Crew Exploration Vehicle (CEV) in This vehicle will be designed to travel both within and outside Earth orbit, and even be capable of interplanetary flight to Mars. The U.S. will also begin a series of lunar robotic missions in Once the shuttle has hauled up the last pieces of the International Space Station in 2010 it will be retired. By 2014, a new launcher will be ready to transport humans in the CEV. In 2015, work will begin on a permanent lunar base, which will be completed by This base will be designed to serve as a launch pad for further exploration, including human exploration of Mars. The U.S. will use the International Space Station only for studying the long-term effects of space on human beings. It will abandon the station completely in Bush s announcement was seen by most observers as an attempt to give NASA a meaningful human space program. The Columbia Accident Investigation Board, in its report, had stated that NASA seemed to lack a compelling mission requiring human presence in space (U.S. News and World Report, January 26, 2004). After Columbia, few people believed that the shuttle missions were worth the risk to life. It was also noted that each launch costs $500-million, and that most activity is devoted to the construction of the International Space Station. It is already four times over its $8-billion budget. Commentators, however, did also point out that the announcement s timing was politically very astute, coming during an obviously popular and successful mission to Mars, and at the beginning of an election year. An editorial in The Washington Post (January 16, 2004) wondered if Bush set a new space agenda without first answering what should have been the fundamental questions: What are desirable space goals for the United States? What are their benefits and costs? What are the best instruments with which to achieve them? CBC News in Review March 2004 Page 55

11 Critics have been quick to pounce on the new plans. Many believe that Bush is not really prepared to fund the new program. Only $1-billion in new money will be available to NASA over the next five years. Another $11-billion is to be reallocated from other NASA programs, and the bulk of that will only become available when the shuttle is retired in Much concern has been expressed over the development of the CEV, the shuttle s replacement. The budget is seen as skimpy, and the process as rushed and, many point out, NASA has a history of spending huge amounts of money on vehicles that never fly. On the other hand, some observers say that the constraints will force NASA to adapt existing rocket technology and update it, and this will contribute to the program s success. Scientists are concerned about other effects of the new NASA program. One of the victims will likely be the Hubble Space Telescope, which will no longer be maintained by shuttle astronauts and will likely fail before its replacement can be launched. Scientists also ask: Why the moon? Is it because the Europeans, Japanese, Indians, and especially the Chinese are all preparing spacecraft to explore it, and the U.S. wants to establish a presence there? Or is it really a good launching point for a Mars mission? Finally, the question remains: Is a Mars mission both desirable and realistic? Robert Zubin, president of the Mars Society, argues that as long as a serious search for life on Mars remains a priority of the space program, humans will need to go there. Only human beings will be able to successfully seek fossil evidence and extant life and answer the real question : The real question is not whether there was ever life on Mars, but whether such life had a common but prior origin from Earth life (The Washington Post, January 11, 2004). Other observers are more cynical, and question the basic purpose of the search for Martian life. Anne Applebaum writes (The Washington Post, January 7, 2004): Also somehow played down is the fact that the search for life on Mars proof, as the enthusiastic have it, that we are not alone in the universe is not a search for sentient beings but rather a search for evidence that billions of years ago there might possibly have been a few microbes. It s hard to see how that sort of information is going to heal our cosmic loneliness, let alone lead to the construction of condo units on Mars. Discussion Much of the impetus to place human beings on Mars is the desire to discover whether it ever did or can support life. Note any other reasons that might motivate future exploration of the planet. CBC News in Review March 2004 Page 56

12 YV MARS INVASION: EXPLORING THE RED PLANET A (Human) Canadian Presence in Space? Further Research To learn more about the Canadian Space Agency go to The United States seems determined to begin a new age of space exploration, one that it hopes will culminate in human exploration of Mars. There is little doubt that Canada, which has participated in the shuttle program, the International Space Station, and robotic missions, will also be asked to take part in this new program. Should Canada commit itself to such a program? In small groups, complete the following organizer. Note arguments for and against Canada s participation in human or robotic missions to explore Mars. Use the first column to focus your ideas. Issues Human Robotic For and Against For and Against Costs and Funding Scientific Advantages Political Advantages (Includes International Relations) Economic Advantages Social Advantages (Includes Public Relations) Safety Once you have completed the organizer, choose the program that you feel would be of greatest benefit to Canada and Canadians. Be prepared to defend your position in a debate. CBC News in Review March 2004 Page 57