Showing posts with label Dava Sobel. Show all posts
Showing posts with label Dava Sobel. Show all posts

Friday, October 19, 2012

Galileo's Daughter



Title: Galileo’s Daughter – A Drama of Science, Faith and Love
Author: Dava Sobel
Publisher:  Fourth Estate, 2000 (First published 1999)
ISBN: 978-0-00763-575-7
Pages: 384

Galileo is considered the father of modern physics, or modern science rather, since the founder of the most basic branch of science may be thought of as the father of modern science as well. However, the endowment of the cherished title is not as a result of a path breaking invention. Rather, Galileo enjoys the pole position due to the vindication of scientific method, the system to test the veracity of a theory by trial and error which survives to this day as the ultimate test to accept or reject a hypothesis. The eminent Italian scientist personified the now famous motto of Royal Society, “Nullius In Verba” (on nobody’s words). He courageously challenged long-held opinions when he found them to be trash, based on his experiments. Religion, which overarched all walks of life during the 17th century, was not prepared to allow a frontal assault on the fabric of their very existence, namely unquestioned faith, go scotfree. The establishment arraigned Galileo of heresy and sentenced him to house arrest. He died while still in custody. Dava Sobel is a renowned science writer, whose work Planets was reviewed earlier in this blog. In this book, Sobel dwells on the biography of the great scientist with recourse to the communications he established with his eldest daughter, Virginia, who was later rechristened Suor Maria Celeste upon becoming a nun. Sobel, true to her stature as a lively author, has lived up to her reputation in making this biography so enchanting, so lucid and so appealing. There is no dearth of biographies of Galileo, but Sobel has did all that were needed to ensure a prominent place for her work in the literature.

Virginia was born out of wedlock, since Galileo never married. Though he had two more children by the same woman, their position in society was always as illegitimate children. They couldn’t hope to be decently married off and Galileo sent both of his daughters to the San Matteo Convent to take up the veil. His real scientific career began at this time, when he refined lens making techniques and made great telescopes for astronomical work. He found four new moons of Jupiter and named them Medicean stars in honour of his patron, the archduke of Tuscany who came from the Medici family, who stood behind their loyal courtier through thick and thin. He also observed sunspots and the periodic fluctuation in Venus’ visible disk, like moon’s cycle.

The publication of details regarding sunspots rekindled the debate whether the sun or earth was moving. The long held view, first propounded by Aristotle and Ptolemy and held dear by the Catholic church was that earth stayed immobile and the other heavenly bodies circled around it. Though Copernicus in 1543 had posited that sun was at the centre, the idea never reached public domain and Copernicus, who was himself a priest, remained silent about it. Now, it fell upon Galileo to claim that the earth moved. The Catholic church might have treated the issue more leniently at some other time, but the 16th century was really a tough one for them, after the Protestant Reformation under Martin Luther. Efforts to reconcile with the breakaways made Vatican convene a series of theological councils, collectively called Council of Trent, which categorically asserted that the Bible must not interpreted by personal choice and it need to be believed as such without question. An ecclesiastical committee called together by Pope Paul V in 1616 stated that Copernicus’ sun-centred theory was heresy and admonished Galileo from adhering to it, to which he readily agreed.

Galileo was pestered with illnesses frequently during the years 1616-23, but it didn’t slow down his intellect. He continued discourse on comets, three of which mysteriously appeared in 1618. In 1623, his star was thought to be in the ascendant, when his long time friend and admirer, Cardinal Barberini ascended papacy as Pope Urban VIII. Galileo immediately started working on his new book, ‘Dialogue on Two Chief World Systems – Ptolemaic and Copernican’ as a comparison between the two. It was structured in the style of a dialogue between three learned men, two supporting Copernicus and one holding on to Ptolemy and the church. The 1616 edict prevented Galileo from coming out in the open in support of his true belief, so he presented it as only a hypothesis. He submitted the completed manuscript to the committee of censors in Rome in 1630, who proposed only minor corrections. The book finally appeared in print in 1632.

Unfortunately, the publication found Urban VIII ill-disposed in general. The Thirty-Years War between German catholics and protestants had engulfed other countries and turned into a European conflagration. The pope was portrayed as a weak one, unable to defend the faith. He grew restless and sleepless over the allegations that he ordered all the birds in his garden killed so as not to be disturbed by their nocturnal calls. Jesuit fathers, who hated Galileo from the start, insinuated against him and his book, making the pope grow into a rage. Pope’s enmity with Galileo’s patron, the Archduke of Tuscany on land issues also precipitated matters. He ordered Galileo to submit in person and explain matters. The inquisition began in April 1633 and met in four sessions in which the 70-year old scientist had to answer gruelling questions about his intentions and true beliefs on the matter. Alert to the imminent punishment, which included torture, Galileo recanted his ideas. On the question of whether he believed Copernican theory, his replay was, “A long time ago, that is, before the decision of the Holy Congregation of the Index, and before I was issued that injunction, I was undecided and regarded the two opinions, those of Ptolemy and Copernicus, as disputable, because either the one or the other could be true in Nature. But after thed said decision, assured by the prudence of the authorities, all my uncertainty stopped, and I held, as I still hold, as most true and indisputable, Ptolemy’s opinion, namely the stability of the Earth and the motion of the Sun” (p.284). Note how cleverly he submitted to authority! Two months later, 7 out of the 10 cardinals in the committee judged that he has committed the offense of heresy and sentenced to imprisonment. He was also forced to kneel before them, and abjure the crime. Stories that Galileo muttered eppur si muove (but it still moves) is probably apocryphal. After a few days in the dungeon in the Holy Office, he was transferred to the Embassy of Tuscany in Rome, then to the archbishop of Siena. The book was properly banned. In 1757, Vatican removed objections to the Copernican theory, but the book remained prohibited. It was finally lifted in 1822 in which year the church could no longer propound its faulty astronomical beliefs.

Galileo was later sent back to his home town of Arcetri near Florence under permanent house arrest. Maria Celeste, his daughter who had looked after his household matters from within the convent, rejoiced at the home coming at last, though her joy was to be short-lived. She was very weak, due to deprivations in the convent and succumbed to an infection from which she never recovered. She died on Apr 2, 1634, four months after her father returned home. She was 33. Galileo laboured on, under immense grief, and completed work on a new manuscript, ‘Two New Sciences’, dealing with mechanics and motion. This was published in 1638 from protestant Holland where the Pope’s writ did not run. By the time he received a copy of his own printed work, Galileo was blind in one eye with cataract. By the next winter, he lost his eyesight completely, while still languishing under house arrest.

The book presents several letters written by the daughter to her father, which are filled with filial piety and attachment. Reading it all together, we wonder whether Galileo was really stone-hearted to send such a loving daughter to the confines of a convent. The book also describes a touching moment when 95 years after Galileo’s death the Church relented a bit and allowed a tomb to be built for him. When his sarcophagus was lifted from the pit, the retrievers were surprised to find a similar one immediately below it. It too contained a skeleton, and they couldn’t identify Galileo’s. Experts were called in, all of them concurred that one skeleton belonged to a woman who had died in her youth, around the same period of the other, aged man’s death. It then dawned on them that they are seeing the remains of the beloved daughter who seemed attached to her father, even in death. Consequently, her remains were also reverently moved to the new tomb.

The book is an excellent one with no blemish to be marked against. It portrays the miserable plight of nuns in contrast to unstained plenty of the higher echelons of clergy. The nuns had to live in self-imposed poverty, couldn’t go out of the four walls of the convent, had their sleep deprived at certain hours for night-time prayers and no recourse to proper medical care in case they fell ill. However, we have to acknowledge with wonder at the things they could handle from inside their convent. Several illustrative diagrams and portraits add interest to the content and are quite engaging. The balance between the emotional and the objective is kept on a razor-sharp knife edge and is kept likewise throughout the narrative.

Plague was a scourge of the ancient world. Many a times it was subjected to the ravages of bubonic plague. The disease, spreading through air, was so contagious and deadly that quarantine was the only effective remedy. Whole families often vanished in a matter of a few days. The lament of poet Francesco Petrarca given in the book when the Black Death robbed him of his beloved wife is worth ruminating on. He exclaimed, “Oh, happy posterity who will not experience such abysmal woe and will look upon our testimony as a fable” (p.209).

The book is highly recommended.

Rating: 4 Star

Sunday, January 9, 2011

The Planets


Title: The Planets
Author: Dava Sobel
Publisher: Harper Perennial 2006 (First published 2005)
ISBN: 978-1-84115-621-7
Pages: 258

Dava Sobel is a famous popular science writer having many titles like Galileo’s Daughter and Longitude to her credit. This is her first book to be reviewed here and from the style of it, I can safely assume that more will follow in due course. Her easy flowing, fluid style has made her a prominent figure in the genre and it is no wonder that an asteroid is named 30935 Davasobel after her. Astronomy is the most stressed aspect of science in many of her works.

The present volume is in essence, a survey of the solar system starting the journey from the hot centre of it all, the sun and ending with the cold extremity, in the Oort Cloud. The author takes each celestial object in turn and explains about them in the context on which that object has enriched popular culture. For Mars, it is science fiction, for Venus it is beauty and for Jupiter, it is astrology! The narration mostly follows this thematic approach proving a great attraction to general audience not well versed in science. On every chapter, the way in which the structures are related to human aspects are carefully laid out.

Mercury is the first of all planets, being closest to the sun. It is associated to the messenger of gods in Greek mythology with Hermes being an alternate name. The perturbations in the orbit of mercury which upset astronomical calculations were long puzzling the scientists as they couldn’t figure out why Newton’s laws are violated in this case. Urbain J J Leverrier, who also found Uranus detected deviations in the perihelion of mercury on every rotation. He proposed that another body, named Vulcan was affecting the orbit due to its gravity, but the painful search by astronomers worldwide failed to locate the elusive body. It was in 1915 that Einstein proposed an answer to the vexing problem in his General Theory of Relativity. He argued that the nature of space-time is different when gravity is very strong like the neighbourhood of the sun and mercury’s orbits were precisely obtained using Einstein’s relativity theory. Spacecraft Mariner 10 flew by the planet in 1974-75 and sent back pictures of its surface full of impact craters, the largest being Caloris Basin. Another mission, christened Messenger is expected to orbit and send pictures later this year.

Venus is the brightest object in the night sky after the moon and reflects 80% of the light it receives due to its cloud cover. The moon would have paled into insignificance if Venus was nearer, as the Moon reflects only 8% of the light it gets from sun. Even though Venus is only second in distance to the sun, it is the hottest planet of the entire system, due to the greenhouse effect of its cloud cover. The atmosphere consists of carbon dioxide, sulphuric acid, hydrochloric acid and hydroflouric acid and the pressure is 90 times atmospheric pressure on earth. Russian crafts Venera and Vega landed there between 1970 and 1984 and pictures were transmitted to earth before the crafts were damaged because of the extreme surface conditions. The craft Magellan circumnavigated the planet for four years from 1990. Radar exploration of the surface features are possible from earth and the largest mountain thus located is named Maxwell Montus in memory of the great Scottish scientist who proposed the theoretical framework of electromagnetic waves of which radar is also a part. All the other surface features are given feminine names to rhyme with the female aspect of the planet of beauty. Many of the characters in womens’ history have found a place there, and even female first names from various countries are chosen.

Describing earth would seem preposterous in a book of astronomy dealing with planets, but the author included it with a prominent theme of exploration of her geography. Attempts on the mapping efforts of its surface, atmosphere and inner parts are given. Earth has a solid core of iron and nickel which rotates at a rate faster than the outer parts by one second a day. Seismologists can hear the sound of the core making upon its contact with the mantle due to this difference in rotating speeds.

The Moon is the only natural satellite of earth and is somewhat larger for a satellite. This causes larger gravitational attraction between the two bodies, making the tidal forces slowing down the rotation of earth by a minute fraction. Meanwhile, the moon drifts away by an inch or two every year. This slowing down and slipping away would end in a stalemate at which earth’s rotation and moon’s recession is stabilized and both would be in a geo-stationary orbit such that moon will be always visible from one hemisphere of earth whereas it would disappear forever from the other.

Mars is smaller than earth, but the early conditions prevailed on the planet allows the possibility of life forms. While all life has been wiped off from the martian soil long ago, the concept of terraforming, the artificial manipulation of the atmosphere is being discussed among the scientific community. Mars is tilted 25 deg about its axis, as compared to earth’s 23.5 deg. This tilt causes seasons as it revolves around the sun, making the polar ice caps consisting of CO2 and water to recede and advance as the seasons change in a martian year of 687 earth days. Crafts Viking 1 and 2 landed there in 1976 and analysed soil samples.

Jupiter is the largest planet and was closely linked to astrology till the time of Galileo. Astronomy and its false brother astrology was separated conclusively, by Galileo’s discovery of the moons of Jupiter which he named Medicean planets to ingratiate himself to his patrons, the Medici family. Astrologers couldn’t assign these new-found objects of anything worthwhile. Astronomy thus proved that it is possible for a planet to have satellites rotating them while at the same time going around the sun as a single system. It conclusively put down earth-centric views on this ground. Jupiter is a gas planet and there is no hard ground to walk on. The Great Red Spot first observed in 1879 is a giant storm raging across the Jovian atmosphere changing colour as time goes on. Scientists believe that the planet has a liquid metallic hydrogen core due to extreme high pressure, is the cause of its magnetic field which is 20,000 times stronger than earth’s. The Jovian magnetosphere even reaches saturn’s orbit, so all of Jupiter’s own satellites are well inside it. A prominent moon, Io, has 150 active volcanoes on the surface due to tidal effects, pouring a constant stream of ions and electrons into the magnetic stream inducing a huge current of several millions of amperes between Io and Jupiter. The space probe Galileo reached Jupiter in 1995 relaying details of its atmosphere.

Saturn was a curious entity for astronomers ever since it was detected to possess concentric rings. The rings containing tiny particles of rock, ice and such space debris may be the remnants of a satellite or planetoid which couldn’t resist the planet’s pull. The spacecraft Cassini flew by the planet in 2004. Close observation of saturn resulted in observing more concentric rings than the three found by telescopic measurements. In fact, it was established that all outer planets starting from Jupiter do possess them.

Uranus and Neptune are similar in many respects. The former was first observed by William Herschel in 1781. Being a long period planet (83.7 years), it was not practical for astronomers to follow it on its course around the sun and obtaining measurements. They tried to extrapolate from previous unintentional observations by other people, but the system failed to obtain correct results. As Mercury’s perturbations were also plaguing the community at that time, it was thought that another planet was deviating Uranus’ path ever so slightly. Very complex theoretical exercises ensued and Urbain J J Leverrier and John Couch Adams did calculations extending over thousands of sheets to pinpoint the location of the planet. The report was published in 1845 and in the very next year, Neptune was observed at the suggested spot by Johann Gottfried Galle. Voyager 2 flew by Uranus in 1986 and by Neptune in 1989. The astronomers were not fully convinced that the deviation of Uranus was due to Neptune alone, as the estimated size of the planet was smaller than the actual. The natural wayout was to look for another planet in the periphery and Pluto was first observed by Clyde Tombaugh in 1930. But later observations from advanced telescopes and probes gave a higher figure for Neptune’s size, obliterating the need for another planet. Compounding on such a revelation was the discovery in 1992 of another Pluto-like object on the fringes of solar system. In 1993, five more planetoids was detected in that area and the fate of Pluto hung in balance. The International Astronomical Union demoted Pluto to a minor planet in the first decade of 21st century. (This fact is not given in the book).

The book provides interesting reading of Columbus on his explorations to the New World. We can deduce the religious zeal affecting the people of those times from Columbus’ self-professed mission statement, “In the name of Our Lord Jesus Christ, sent by the most Christian, exalted, excellent, and powerful princes’ the King and Queen of Spain, to the regions of India, to see the Princes there and the peoples and the lands, and to learn of their disposition, and of everything, and the measures which could be taken for their conversion to our Holy Faith” (p.79).

Even though appealing to readers who are staunch believers, some references in the book equating revelations in scripture with scientific concepts might be grating on the nerves of sceptics. The author has included those portions without any logical basis other than placating a section of her audience. Take for instance that solar eclipse can be total only on earth, because the moon is apparently the same size as the sun because of its shorter distance. The author asks “Is this startling manifestation of the sun’s hidden splendour part of a divine design?”. Superfluous and avoidable argument, really. In another part she says that solar wind is reminiscent of the wind from god mentioned in the Bible. In the chapter on Jupiter, the author examines Galileo’s horoscope and argues that some of the predictions had come true, while several of them failed equally. She then proposes to vindicate even the failed ones, the prediction that he would do foreign travel being one of them. Galileo never set foot outside Italy, but the author asserts that his invention, the telescope has virtually made him go far off places. Such unscientific mumbo jumbo would rather better be omitted from such books. The chapter on Venus is laced with poetry, some of them really amazing, but one gets the impression that it was overdone. Also, the thematic collection of ideas which the author takes pride in, is not as appealing as she might have thought. Saturn’s theme was music, but it was dull and rather short, leaving much to be desired.

The book is recommended.

Rating: 3 Star