Title: Telescopes in India
Author: Mohan Sundara Rajan
Publisher: National Book Trust, India 2009 (First)
ISBN: 978-81-237-5637-0
Pages: 308
Books on the popular science genre are very rare to originate in India, though the country is a hot selling place for good books from England and the U.S. Boasting of the world’s largest English-speaking technical population after the U.S., this is no wonder. Mohan Sundara Rajan is an eminent science writer, with over three decades of experience in media. He is the author of sixteen popular science books including Space Today, Wireless: The Telecom Story. He is the recipient of several awards including the National Award for Outstanding Effort in popular science communication. The current title seeks to bring out the features of various telescopes installed in India as well as carrying out a survey of the field among international institutions and academia. The book is the first of its kind and definitely caters to a crying need for raising awareness of the country’s scientific potential among the future scientists and to instil in them the scientific temper, as enshrined in the Constitution. Coming right from a reputed writer, the book seems to address all the above issues satisfactorily, at first sight.
400th anniversary of the discovery of telescope was celebrated in 2008. Hans Lipperhey of Netherlands patented the device, named spy glass in early 17th century. Galileo Galilei, in Italy, heard of the instrument and devised one, without actually seeing a model in 1608. To commemorate the event, 2009 was declared to be the International Year of Astronomy. Perfect timing for a book on astronomy to come out! Developments in telescopes continued apace in Galileo’s century, as Robert Hooke built a reflecting telescope in 1664 and the Paris Observatory was founded in 1667. The author gives a detailed list of the various developments including principles, types and inventions, which occurred in the field of telescopes which is a good read. Today, computers and fiber optics has taken over the field and it is no longer necessary for a person to be at the eyepiece of a telescope. Remote control methods have helped him to be halfway around the globe and still obtain a glimpse of the heavens through its objective lens. No longer do they need to keep awake in the dead cold of the night. The capability of the instrument is the single factor which puts a limit on the astronomer’s efforts. Atmospheric dust and turbulence cause immense trouble for sky watching, which is compensated by a technique called adaptive optics. It adjusts for distortions in the wavefront by obtaining a reference image from a natural, bright star nearby or by artificially producing a speck of light among the sodium atoms, situated 90 km above earth, by shining a powerful laser beam on it. The data from these measurements are used to mechanically adjust the tiny mirrors on the telescope to compensate for atmospheric blur.
Modern astronomy in India is said to begin when Sir Thomas Roe, Queen Victoria’s representative to the court of Jahangir presented a set of ‘prospective glasses’ (as telescopes were then called) to the emperor in 1616. India was not much behind the world at that time, since the telescope was first used by Galileo only eight years previously. An Englishman, Shakerley observed the transit of mercury in 1651 at Surat. The Indian kings were suitably impressed by the new development that the Rajahs of Jaipur, Awadh and Travancore built observatories. However, the first astronomical observatory with good telescopes was a foreign contribution, which was built in Chennai in 1790. It set the reference meridian in India for timekeeping and that’s why Indian Standard Time is set for 82 deg 30 min east longitude, which is the coordinate of the observatory. Larger telescopes were later installed at Madras (as Chennai was called) and the fixed meridian formed the basis of the Great Trigonometrical Survey of India in 1802. Indians also worked in the observatory, with Chintamani Ragoonathachary discovering the variable star R. Reticuli in 1867, which is the first recorded astronomical discovery by an Indian. The observatory was shifted to cool Kodaikanal in 1899. Other observatories established after independence were at Nainital (1955), Kavalur, Tamil Nadu (1967), Radio telescope at Ooty (1970), Gauribidanur (1979) and Hanle, Ladakh (2000), which is also the highest optical telescope in the world. Kodaikanal Observatory is dedicated for solar observations, documenting the sunspot cycles and analysing possible links to monsoon and among them Kurinji blooms which occur once in 12 years!
Solar observations at Udaipur, Rajastan began in 1975 and later taken over by the government. The institution is ideally located in the middle of a lake, helping to reduce atmospheric turbulence. This is also a part of the Global Oscillations Network Group (GONG), which is an interconnected network of six worldwide telescopes observing the sun and sharing data among each other. Dr. Sampurnanand, the then chief minister of U.P. was instrumental in setting up the observatory at Nainital, with one telescope now named after him. A larger telescope is now being planned at Devastal, near Nainital. Dr. Vainu Bappu, the noted astronomer and space scientist was deeply involved in setting up a 2.3 m optical telescope at Kavalur, in a densely forested area. The need for dark, clear nights prompted the scientific community to seek a suitable place in the Himalayas which they did in setting up the Himalayan Chandra Telescope at Hanle, Ladakh. This telescope can also be controlled remotely from Hoskote, near Bangalore. Another 2 m optical telescope, called National Large Solar Telescope is being planned at the same location.
The 20th century saw more windows opening to observe the sky in the radio, ultraviolet and infrared bands. These waves are not as affected by terrestrial turbulences. Radio telescope was commissioned at Ooty in 1970. Giant Metre Wave Radio Telescope at Khodad, Pune went functional with thirty dishes of 45m diameter, for observing quasars, pulsars and galaxies. Gauribidanur also houses a radio array for observing the sun at short wavelengths. This Radio Heliograph was commissioned in the 1970s. India has potential to observe gamma rays which are high-energy rays coming from deep space, from ground as well as space based telescopes in satellites. AstroSAT, a satellite built by ISRO will carry five telescopes to cover broad X-ray regions as well as UV and optical bands.
The book is endowed with neatly and succinctly laid out illustrations for making the point sink. Also, being the first book of its kind in India carries its own sheen. The glossary given at the end is comprehensive and does its work of explaining the concepts in two or three sentences exceedingly well.
Well, those are the good points which can be shown in favour of the book. On the other side, drawbacks abound. The info boxes which are interspersed throughout the text is slightly distracting the reader from the main topic, even though they are informative. The illustrations are technical and unappealing to the lay reader. The drawings are also intended for science papers rather than a book on popular science. At times, we get the impression that the book is based on outdated data, as in the section on liquid mirron telescopes, where it says, “Liquid mirror telescopes became a reality in recent times (1980s), when CCDs came into use” (p.64). Remember that the book was first published in 2009. Probably, the author copied this sentence as a whole from a reference and didn’t bother to update it. Most of the material on Indian telescopes is rooted on a tone of propaganda, with all good and nothing bad! Extravagant praise for administrators and officialdom don’t give credence to a science book. The language is highly technical, which are not enunciated in detail. It assumes an undignifying pose sometimes, when the author refers to scientists as the American, or like the Germans are building a telescope or the theory was verified by an Australian, with the name of the scientist not even mentioned. A gross error is also suspected in page 174, where the author claims that the most distant stars are the youngest! This is clearly not true. The most distant stars are that much away because the expansion continuing since the big bang has taken them far. Hence, they are the oldest stars in the universe.
Mohan Sundara Rajan also supports unproved hypotheses and unsubstantiated theories as if accepting them at face value and putting doubt on the veracity of long established theories in astronomy. It is true that the long entrenched theories may turn out to be wrong, in light of new evidence to the contrary, but as such, those principles are unassailable with the current state of knowledge. The author says the solar observations have assumed significance on the basis of new theories that the sun has a solid core and nuclear fusion is not the energy source of it. This is outrageously far fetched. Solar observations are significant because of the thorough influence the sun exerts on our planet and not due to some outlandish, unverified theory. He also praises the opinion of an amateur astronomer and telescope maker from Chennai, Prof. P Devadas that lunar craters have igneous and volcanic origins, rather than meteor impacts. Here again, the author relies on authority and not on reason and verification. This is highly unbecoming of an author claiming to be an eminent science writer! He can only pollute young minds at the worst, with this style of science reporting. The book is generally free of printing mistakes, but when they appear, the effect is comic, as in page 283, “In fact, some of the images produced by ground-based telephones were better than the Hubble Space Telescope, the most expensive eye in the sky”. The narration is artificial and uninteresting making the reader suspicious that he has reproduced some paragraphs literally from glossy leaflets supplied along with new products because the author has not made any effort to make them lighter. School students would obviously find the book quite useful for collecting data and pictures on Indian astronomical programs as it abounds in them. Apart from that, a serious reader is made miserable by reading it in full from cover to cover.
The book is recommended for school students on the look out for collecting data for their projects.
Rating: 2 Star
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