People's Democracy(Weekly Organ of the Communist Party of India (Marxist) |
Vol. XXXII
No.
42 October 26, 2008 |
India�s Moon Mission
Raghu
DESPITE heavy rain over several previous days, the skies cleared sufficiently early Wednesday (October 22) morning over Sriharikota to enable a textbook launch of India�s historic and first mission to the Moon. At the time of going to press, the Chandrayaan-1 satellite was in orbit around Earth awaiting a series of sling shots that would take it to its destination orbit around the Moon, after which the mission�s scientific studies would start.
Even though many crucial hurdles remain to be crossed, the successful launch itself has been greeted with euphoria in India and significant notice abroad. Chandrayaan (�vehicle to the moon� in Sanskrit) has been widely hailed as showcasing India�s growing and impressive capabilities in space technologies and as a welcome addition to the pool of scientific knowledge about the moon and, indirectly, about the Earth and the wider solar system. But it has also received some criticism, chiefly that such missions yield little tangible benefit, that developing countries like India can ill afford such esoteric experiments and that the considerable sums of money spent of them are incongruous in a nation still plagued by chronic poverty.
This article takes a close look at the goals and tools of the mission, its significance for India both in science and technology and in a broader strategic sense, and also examines the issues raised by critiques of this mission which may also apply to space exploration in general.
Chandrayaan in context
The Mission itself is certainly not pathbreaking within the overall context of international space exploration. Chandrayaan may be India�s first mission to the Moon, but there have been as many as 68 others.
The former USSR conducted the first moon mission on Jan 2, 1959, followed swiftly by the US in March the same year. Japan broke the superpower duopoly in January 1990 by sending a spacecraft to orbit the moon, but with mixed results, followed by the successful Kaguya launch in 2006. The European Space Agency (ESA) launched a lunar probe in September 2003 and China sent its spacecraft Chang-e 1 to orbit the Moon in 2007. India is therefore the sixth nation (counting the EU as one entity) to demonstrate its capability to reach the Moon and, at least nascently, beyond.
After the flurry of unmanned Moon Missions in the 60s, and the dramatic manned missions by the US starting in 1969, interest in the Moon waned, with no lunar missions for almost 15 years during the 80s and 90s. Of late, though, there has been a sharp revival in lunar missions, prompted partly by the arrival of new players in the space, and perhaps more so, by the availability of improved technologies with a promise of richer findings. The USA has announced a $100 billion programme to return to the Moon by 2018, with all-new launcher and lander, the Moon being used here to test technologies for an extensive Mars mission.
So
the question is, is India merely reinventing the wheel in a �me
too� mission?
Chandrayaan basics
The Indian Moon Mission, Chandrayaan, was approved by the government in November 2003 on the basis of a proposal by Indian Space Research Organisation (ISRO) developed over several years of spade work and peer review. Whereas India has launched many a rocket and placed several satellites in orbit around Earth, Chandrayaan is India�s first mission out of the near-Earth environment into deep space, a term nominally used to describe space beyond 100,000 km from Earth. In that sense alone, the Mission marks a significant scaling-up of India�s space programme and of technologies in several fields.
Chandrayaan-1 was launched by an upgraded version of ISRO's work horse Polar Satellite Launch Vehicle (PSLV) with more powerful rockets and more propellant. This was the 14th PSLV launch, with only one failure, and a total of 29 satellites have been put into a variety of Earth orbits by them. The PSLV launch of the Chandrayaan, relatively heavy at 1304 kg, and its accurate placement in transfer orbit, has solidified ISRO�s reputations as a reliable and cost-effective launch service provider, about which more later.
Perhaps the most significant technological up-scaling of India�s space capabilities under Chandrayaan has been the setting up of the Indian Deep Space Network (IDSN) consisting of an 18-m and a 32-m antenna at a new campus in Byalalu near Bengaluru. Whereas existing tracking stations are being upgraded to support the mission during the launch and early Earth Transfer Orbits up to a range of about 100,000 km, the new antennae will perform the tracking and control functions, and real-time downloading of information from the scientific instruments over the much greater distances of over 400,000 km involved in the lunar mission. More importantly, while the 18-m antenna is tailored specifically for Chandrayaan-1 mission, the state-of-art 32-m antenna can also support other planetary missions, for instance to Mars.
Mission & Payloads
So far only the first steps of the Mission have been covered. Chandrayaan was placed in its first orbit around Earth within about 18 minutes from launch and then into a highly elliptical orbit 22,858 km away from Earth at its longest (apogee) and 247 km away at its nearest (perigee). At suitable times, and after sufficient momentum has been gathered, the spacecraft�s motors would undertake a series of �sling-shot� firings to lift the craft to higher and more extremely elliptical orbits, the last with apogee at 3,86,194 km bringing it almost to the moon (see figure).
At around 2,00,000 km from Earth, the satellite will begin to experience significant pull from the Moon�s gravity, increasing as the craft gets closer to the Moon. At roughly 60,000 km from the Moon, the craft would have reached what is called Lagrange Point No.1 when it is ready for �capture� by Moon�s gravity. At this point, the craft is slowed down, allowed to be captured by the Moon, and its orbit further lowered to its ultimate intended 100 km circular orbit around the Moon where it will stay for 2 years.
Following this, the Moon Impact Probe (MIP) would be ejected from Chandrayaan to crash onto the Moon�s surface, conducting various observations mostly on the way down but also after impact. Contrary to a lot of chatter in the media about �planting the Indian flag�, the MIP, having crashed, would be in no position to do this, but has been painted with the Indian tricolour to symbolically register India�s arrival on the Moon.
Chandrayaan carries 11 payloads, 5 Indian and 6 from different international partners, to carry out various tasks together contributing to the main scientific objectives of the Mission, namely to prepare a 3-dimensional atlas of the Moon covering both the bright and dark sides and to conduct detailed studies on the distribution of various important chemicals and minerals, on the existence and availability of water ice (so called to distinguish it from other frozen liquids) and others while also seeking to develop and test different instruments.
Images and information on the composition of the very thin lunar atmosphere and of the fine dust thrown up by the landing impact would be sent back by the MIP throughout its descent and landing, and are expected to be useful in planning future missions especially soft landings. The spacecraft�s Terrain Mapping Camera would send back 3-dimensional images of the lunar surface with high spatial and altitude resolution of 10 metres or lower. All earlier moon missions, including the US and Soviet manned and unmanned lunar missions, have together only looked at a relatively small area of the Moon�s surface, mostly on the bright side, so Chandrayaan�s 3-D atlas of the Moon will be a major new contribution.
The other Indian payloads include a High Spectral Imager (HySI) which will gather and transmit high-resolution mineralogical data of the lunar surface and also about the Moon�s lower crust by looking in craters at material that could have been brought up by crashing meteorites. A Lunar Ranger Laser Instrument (LRLI) will study the Moon�s topography and especially its gravity field about which very little is known, using lasers rarely used on the Moon. Adding significant value to the data, a High-Energy X-Ray (HEX) Spectrometer will conduct so far the highest resolution X-ray studies whose main aim is to examine the possibility of water having traveled to the lunar poles.
The spacecraft carries 6 international payloads selected on the basis of an Announcement of Opportunity by ISRO which has levied no charge thus conveying its commitment to international scientific collaboration.
Chandrayaan is the first partnership of USA�s NASA with India�s space programme. Given the hiatus in American lunar missions, and its declared intention to return to the Moon in 2018, Chandrayaan has given NASA an opportunity to explore and study new potential landing sites through a Miniature Synthetic Aperture Radar (MiniSAR) which will also search for ice deposits near the lunar poles. NASA also has a Moon Mineralogy Mapper (M3) to map the composition and geographical distribution of mineral resources on the lunar surface, particularly on the permanently shadowed north and south polar regions.
The European Space Agency (ESA) has put on board 3 instruments which were also deployed on its earlier SMART-1 (Small Missions for Advanced Research in Technology) lunar probe, but which would study the Moon over greater area and more intensively on Chandrayaan-1. An X-ray Spectrometer would look for and assess quantities of several elements, particularly magnesium and iron, which could give a clue as to the history of the Moon such as whether its surface was earlier molten magma. An Atom Reflecting Analyser would try to track and capture images of atoms taking off due to solar wind activity in the absence of a magnetosphere or atmosphere on the moon, while another near-infrared spectrometer would examine the composition of the Moon�s surface.
A new and interesting experiment is the Bulgarian RADOM or Radiation Dome Monitoring Experiment which will study the effects of radiation in the lunar and near-lunar environments. Such radiation is known to be a hazard to humans during extended stay in space and this study is expected to result in better predictive ability and design of protection gear for future space crews.
Consensus in the global scientific community is that these instruments, along with the infrastructure and methodologies of their deployment, represent a considerable advance over earlier efforts at gathering scientific data on and about the Moon.
Cost and Benefits?
Whenever issues of space exploration are discussed, questions arise as to the benefit to humans of the knowledge or experience generated, and especially whether the cost justifies these benefits. And it is common for such discussions to veer around to the spin-off benefits of space technologies, famous examples being Velcro fasteners, non-stick pans, alternative applications for space suits and so on. Of course, all technology development, especially in unfamiliar or extreme environments (and space is both) will have spin-off benefits. But this writer has always believed that no amount of frying pans can be used to weigh cost-benefits of space science. Science has always advanced through the quest for new knowledge and pushing known boundaries. And practical applications and benefits to human society have always followed, somewhat later, but often in ways that could not have been predicted earlier. Should early humans have asked what benefits could be expected by observing and calculating the movement of planetary bodies?
Of course, society should always weigh the costs and foreseeable benefits of science and of the knowledge that is sought to be generated. In this case, some aspects need to be put in perspective.
It is well known that basic science research is the foundation of advanced technological capabilities of a nation, and that India has lagged far behind what is desirable in this regard for many decades now. The space programme offers one of the unfortunately rare theatres of scientific activity that can give a fillip to basic research in the country. Peer review of the Chandrayaan mission proposal also noted this as one of the important considerations in giving it approval, as did the Parliamentary Standing Committee on Science & Technology.
A lot of comment has been made about the �high cost� of Chandrayaan in a poor country such as India. The total cost of Chandrayaan is Rs 360 crore or about $80 million. This includes about $20m for the Deep Space Network whose infrastructure will be available for all future deep space missions. Europe�s SMART-1 mission cost about $180m which is itself about one-fifth of usual European scientific space missions. Japan�s Kaguya lunar probe cost $487m and even China�s Change-1 cost $180 million.
Chandrayaan�s cost of $80m is roughly equal to that of a medium sized passenger aircraft such as the stretched version of the Boeing 737 which costs $75-80m, while the long-haul Boeing 777 passenger jet required by Air India costs about $240m!
Not only is the Chandrayaan cost effective relative to similar missions by other nations, this relative low cost is itself a tremendous advertisement for Indian space services in a highly competitive launch industry, and will help generate enormous revenues for ISRO and its commercial arm, Antrix.
The big question mark does not belong with Chandrayaan-1 but with the projected manned lunar mission currently spoken of in 2020. There is absolutely no evidence to support any additional benefit of manned lunar landings, as compared to, say, space crew spending extended periods in a space station. The cost would be enormous with little benefit to show for it except for some chest thumping.
Speaking of which, the media coverage of and comments about Chandrayaan have revealed two disturbing trends.
The first was unnecessary jingoism, going far beyond justified national pride. And the second, more seriously, was its extension in projecting national advantage rather than a gain for the common human heritage. Some commentators spoke of the planting of the Indian flag as giving the right to India to extract minerals from the Moon at some future date, reminding one of the worst of colonialism when Europeans went around planting national flags in other peoples� countries and �claiming� these territories as their own to exploit. Even some ISRO spokespersons and retired space scientists have regrettably spoken grandly about the possibility of future extraction of minerals from the Moon. Unfortunately, the international Space Treaty of 1967 and the Moon Agreement of 1979 are both silent on both such exploitation and on militarisation of the Moon. Rather than join the US and some other nations in a race to exploit the Moon or use it for military purposes, India should take the lead in pushing for international agreements to prevent militarisation of the Moon and any use of the Moon, such as national or private exploitation, that does not benefit all of humankind without damaging our planetary neighbour like we have damaged our own planet.
Chandrayaan satellite