jects in near-Earth orbits, to a possible Earth-orbiting 

 space station with military applications, and to mili- 

 tary vehicles supporting the Star Wars program, no 

 effort was made to exploit this infrequent close ap- 

 proach to Mars. The European Space Agency, which 

 expended major resources to rendezvous with Halley's 

 Comet two years ago, also did not plan any project to 

 take advantage of this, but the Russians did. 



In July of last year the Soviet Union launched two 

 spacecraft from their Baikonur Cosmodrome in central 

 Asia. The plan was for these craft to arrive in the vicin- 

 ity of Mars in 200 (Earth) days and go into orbit around 

 it. The orbits would be made circular and synchronous 

 with that of Phobos. During April and May of this year 

 landing vehicles will be deployed and these will make a 

 series of low-velocit flybys of that little moon. The 

 orbiters are expected to be active for at least 140 

 (Earth) days after the landers are released. The Soviets 

 are not running the whole operation by themselves. 

 Participants include scientists from Finland, West 

 Germany, France, East Germany, Bulgaria, Austria, and 

 the United States, which is providing ten scientists. 



After the landers make their flybys they will land on 

 Phobos's surface. The landers are of two types. One 

 kind is to be stationary (called the DAS lander after its 

 name in Russian). It will deploy a series of instruments 

 to measure the chemical and physical features of Pho- 

 bos. The other kind is a mobile vehicle that will move 

 over the surface, making some of the same measure- 

 ments to see if composition and physical features 

 change from place to place. The mobile lander will 

 move in a very odd way compared to the rover vehicles 

 the U.S. sent to the moon years ago. Because Phobos is 

 so small and lumpy, a rover would have serious prob- 

 lems moving about. The lander is this case is called a 

 hopper. It is going to literally hop from place to place. 

 When the hopper completes its measurements in one 

 place, pusher legs will propel it to a new place. Each 

 hop will carry it about 65 feet (20 meters). After a hop 

 is completed, the hopper will bring itself into an up- 

 right position and make a new series of measurements. 

 It is capable of making ten such hops. This kind of 

 vehicle is practical on Phobos, which is so small its 

 gravitational pull is very weak. It doesn't take a lot of 

 energy to propel the hopper. 



The stationary (DAS) landers are instrumented to 

 make a greater variety of physical and chemical 

 measurements. It is expected they will continue to 

 make measurements for about one (Earth) year. The 

 main part of the mission is expected to take about three 

 months. Besides the gathering of chemical and physi- 



cal data, television cameras will scan the surface, send- 

 ing back high-resolution images to Earth. The project, 

 however, isn't without its risks. What the plans are and 

 how it all actually functions may be somewhat dif- 

 ferent. One of the Soviet scientists said recently, "It is 

 worth the gamble, and if things work we should have 

 some fantastic data from what will be the first landings 

 on a small body in the Solar System." 



Many glitches could arise. The DAS landers will be 

 powered by solar panels. If one of these landers ends up 

 landing in the bottom of one of the many craters that 

 pock the Phobos surface it could find itself covered by 

 permanent shadows from the crater rim. The initial 

 power would fade quickly and the solar panels could 

 not recharge the system. So, all data transmission 

 would shut down. Even if a DAS lander happens to land 

 on high ground in full sunlight, it could be oriented in 

 such a way that the data transmission antenna, aimed 

 towards Earth, would cast a shadow across the solar 

 panel, again shutting off all power. Finally, if the land- 

 er finds itself on the side of a hill, the angle of its solar 

 panel to the sun could be so poor that although power 

 might not be cut off, it would be reduced considerably. 



The experiments in this mission sound like some- 

 thing from science fiction. They sport such acronyms 

 as LIMA-D, GRUNT, DION, FREGAT and KRFM-ISM- 

 THERMOSCAN. One of the experiments is of special 

 interest to Chicagoans. It is a device called an alpha- 

 backscatter spectrometer that makes chemical measure- 

 ments on the surface. It was originally developed by 

 Prof. Anthony Turkevich, of the University of Chi- 

 cago's Department of Chemistry. It is designed to func- 

 tion best in high vacuum, and this condition is met on 

 the surfaces of both our moon and Phobos. It was car- 

 ried on many of the early unmanned Surveyor missions 

 that landed on our moon in the middle 1960s. It pro- 

 vided such good analyses of our moon's surface that it 

 was possible to predict some of the rock types that we 

 could expect to find when the Apollo missions finally 

 went to the moon to collect samples. 



It will be fascinating if even a part of all this comes 

 off without too many hitches. Already there has been 

 one major failure. Due to an error by a Soviet ground 

 controller, one of the two spacecraft on the mission 

 was accidentally destroyed last September on its way to 

 Mars. There is, however, still the other spacecraft with 

 its landers and instruments. 



All of us in space research hope that the god Mars 

 will take kindly to this latest incursion into his piece of 

 space and not turn Deimos and Phobos against us puny 

 Earthlings as he did so long ago. Fll 23 



