Teign u3a great Lives 2014/15


CARL EDWARD SAGAN (1934 – 1996)



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CARL EDWARD SAGAN

(1934 – 1996)


Carl Sagan was one the founders of the modern disciplines of planetary science and exobiology and he was a brilliant educator who was able to inspire public interest in science. A visionary and committed defender of rational scientific thinking, he transcended the usual categories of academia to become one of the world's best known scientists and a true celebrity. Sagan fuelled his careers with a wealth of talent, a slice of good luck, and an intense focused drive to succeed. He made a lifelong study to understand our planetary system, to search for life beyond earth, to further man's exploration of deep space and to communicate the thrill of all scientific discoveries to others. As an advisor to NASA and as an important member of the science teams for the Mariner, Viking, Voyager and Galileo space missions, he was at the centre of the scientific exploration of the solar system. He was also all his adult life a highly popular teacher, taking much pride in passing on his knowledge to a future generation, writing over 600 academic papers on his subjects. His influence reached far beyond the classroom though and he became known throughout the world for his vivid and comprehensible writing, writing/co-writing more than 20 books in an idiom that let scientific thought be understood by those with no more than a passing knowledge. Most especially he became famous for his ground breaking TV series Cosmos, which was at the time the most watched TV show in history, being watched by more than 500 million viewers in 60 countries. Nearly 20 years after his death he remains one of the most well-known and important scientific figures of the 20th century.

He was born in Brooklyn, New York of working class Jewish parents and, whilst not well educated themselves, they encouraged him to read, count and think from an early age. His love of space and stars began early and from the age of 6 he was fascinated by the stars to the extent that as a result of some confusion at his local public library he was presented with a book on Hollywood idols rather than constellations! The librarian couldn't believe that such a young person would be requesting a book on space and stars. He is quoted as saying that the only thing he ever wanted to do from childhood was learn about the planets and the stars. He also believed that everyone is born a scientist, but kids get put off by adults telling them it isn't practical, something however his own parents didn't say to him.


Education


After High School he went to Chicago University and in 1954 received a BA in Arts with General and Special Honours after following a broadly based 'Great Books' programme as the University didn't allow early specialisation on the basis that if you arrived there you were confessing ignorance, because if you knew stuff you wouldn't be there and if you were ignorant you were in no position to say what you wanted to specialise in! In the end he always said that he was grateful for the opportunity to study things he had never considered before, such as art, architecture, music, Greek playwrights, and cultural anthropology. In 1955 he gained a BSc in Physics and his Masters in Physics the following year. In 1960 he was awarded a PhD in Astronomy and Astrophysics, working under Gerald Kuiper, the leading astronomer at the time in the new speciality of Planetary Science (the Kuiper Belt and its Objects take their name from him).




Some important theories he formulated




Nature of Venus – Sagan's doctoral thesis resolved the argument in the scientific community regarding the nature of Venus and whether it had a cool surface (as generally believed at the time) or a hot one (as Sagan theoretically proved). His theory brought the notion of greenhouse gas effects into common currency and although controversial at first, his theory was confirmed by both the Russian Venera and American Mariner spacecraft missions when they succeeded in landing on Venus. With his long term collaborator James Pollock he refined his thesis into a series of papers written between 1965 and 1976 that have become definitive studies of the 'run-away greenhouse effect'.

Seasonal changes on Mars and Nuclear Winter – Before Mars had been reached by spacecraft the dominant theory was of surface conditions that whilst harsh, still might support life. This was based on telescope observations that showed seasonal waves of darkening widely believed to be vegetation changes. Between 1966 and 1970 Sagan and Pollack worked on a theory that this could be caused by wind-blown dust responding to seasonal wind patterns. Observations had already shown that Mars had a low atmospheric pressure and apparently large differences in elevation to develop realistic models of the Martian atmospheric circulation. These indicated that the planet would be swept periodically enormous dust storms. When Mariner 9 and Vikings 1 and 2 reached Mars they revealed vast planet wide dust storms driven by seasonal winds (in 1971when Mariner 9 reached Mars it found the entire surface completely obscured by one such storm, except for the tops of four enormous volcanoes). Sagan and his team refined the data to develop highly sophisticated dust transport and planetary circulation models for Mars and then applied them to earth like conditions, initially to better understand high altitude spread of aerosols from volcanic eruptions and their climate effects. This led Sagan, a life-long opponent of nuclear weapons, to define the concept of “Nuclear Winter” a concept that whilst considered overblown today did trigger a continuing huge scientific controversy.

Complex Organic Molecules – the origin of life – With colleague Bishun Khare he built on the earlier work of Stanley Miller to show that the gases present on the early earth (mostly methane, ammonia and hydrogen sulphide) when subjected to ultra–violet light and charged particles produced sulphur containing amino acids and the chemical building blocks of DNA and a dark red substance they named Tholin (Greek for mud). Once deeper space exploration took place it was shown that this substance is widely present throughout the solar system, including Saturn's moon Titan and comets and asteroids. The tholins on Titan when added to water produce further amino acids and as there is frozen water on Titan it may just need warming up to produce life.


Space Exploration


Sagan never flew in space but he will always be associated with four major space flights for as long as the spacecraft survive.



Pioneers 10 and 11 – These craft were launched in 1972 and 1973 respectively to explore the asteroid belt between Mars and Jupiter and then Jupiter itself with its cohort of moons. After this they were accelerated by Jupiter's gravity to head out of the solar system in opposite directions. Neither has been aimed at any nearby objects. Pioneer 10 was deliberately aimed at a point on the boundary of the constellations of Orion and Taurus where there are no nearby objects. If either are to be found they will have to be encountered by an advanced space-going civilization. Sagan's interest in extra-terrestrial life was triggered and at very short notice (three weeks) before the launch of Pioneer 10 convinced NASA to attach a gold-anodized aluminium plaque to the spaceship. The plaque was designed by Sagan, his wife Linda and the scientist Frank Drake. The expected erosion rate in interstellar space is sufficiently small that the message on the plaque should remain intact for hundreds of millions of years. The plaque shows the position of the earth in its solar system and also shows the human form.

Voyagers 1 and 2 – These craft were launched in August and September 1977 to achieve a “Grand Tour” of the outer solar system before heading out into interstellar space, although in the end only Voyager 2 got to Uranus and Neptune as Voyager 1 was diverted to have a look at Titan. This time Sagan and his colleagues had longer to plan a suitable message to accompany the crafts. Affixed to each craft is a gold plated record, complete with cartridge and stylus enclosed within an aluminium record sleeve on which is printed (in scientific notation) the instructions for playing. The record contains, amongst other things: greetings in 59 human languages and one whale language; a 12 minute sound essay including a kiss and a baby's cry; 116 encoded pictures; and 90 minutes of recorded music up to the mid-1970s. Sagan recognised that there was virtually no chance of that either of the Voyagers would ever enter another solar system, even if every star had a planetary system. He believed that the craft themselves was a potent message. He said that “Perhaps no-one in 5 billion years will come upon them. 5 billion years is a long time. By then all humans will be extinct....none of our artefacts will have survived on Earth, if the planet is still in existence....more likely the evolution of the Sun will have burned the Earth to a crisp or reduced it to a whirl of atoms. Far from home, untouched by these remote events, the Voyagers, bearing the memories of a world that is no more will fly on.”

As a final salute to the Earth and the solar system, Sagan persuaded NASA to turn Voyager 1’s camera back towards the Earth as it was speeding away beyond Neptune and take a family photo of the solar system. The picture of Earth from the depths of space showed a barely visible pale blue dot against a background of stars. By accident because of sunlight reflecting of the spacecraft, Earth is sitting in a beam of light. Sagan used the image to show the smallness and fragility of our home planet in the immensity of space. That little dot contains the whole of human history, everyone and everything that we have known. That's home – a mote of dust suspended in a sunbeam.



Cosmos – The Television Series – Sagan believed that science should be disseminated to as wide an audience as possible and by the mid-1970s he was frustrated by the waning of public interest in space and the increasing questioning of the value of the American space programme. Following some success on TV due to his flawless ability to explain in easily accessible language and his quick and witty delivery which captured the audience's attention, he decided that a dedicated series on astronomy and cosmology could be delivered to the general public. By 1980 he had succeeded in interesting the Public Broadcasting Service to produce an ambitious 13 part TV series looking at these subjects, but presented with a very broad human perspective, aimed at the popular audience and designed to be visually and musically stunning. The result was Cosmos, a blockbusting 13 hour series. There is no short way to describe all the topics covered, you'll just have to watch it for yourselves. Today some of the special effects may be a little dated but the clarity and enthusiasm of Sagan's presentation make it compulsive viewing and better than the recent re-make! It won both Emmy and Peabody awards and the accompanying book was on the New York Times best-seller list for 70 weeks.

Later Work – Following the success of the Cosmos series Sagan went back to teaching at Cornell and continued to write, winning a Pulitzer Prize for his book The Dragons of Eden: Speculations on the Evolution of Human

Intelligence. His popularity and ability to make science interesting and understandable led to repeated invitations to write fiction as well as non-fiction. After resisting for a while he succumbed and wrote a science fiction novel Contact in 1985, because he felt that this was a further way of presenting the search for extra-terrestrial intelligence to a broader audience. The book was made into a film with Jodie Foster in 1997.

He continued to work for NASA on the Voyager programme and the Galileo mission to Jupiter, launched in 1990. He suggested calibrating the craft for its task by doing a research fly-by of Earth after launch. Pleasingly the fly-by was able to deduce an oxygen atmosphere, water, clouds, oceans, polar ice, life and intelligence. Sagan is said to be have commented that he doubted the last result!

Sagan received many awards and honours, including the NASA Distinguished Public Service Medal (twice), The Rittenhouse Medal of the Franklin Institute, The Orsted Medal of the American Physics Teachers Association and the Annenberg Foundation Prize for astronomy education. In 1994 he was awarded the Public Welfare Medal from the National Academy of Science.



Marriages, Family and Death – He was married three times. In 1957 he married Lynn Margulis, a fellow student, with whom he had two sons. His marriage broke down in 1963 and he was divorced. In 1968 he married Linda Salzman, an artist, with whom he had a son. During the work he undertook leading up to the making of Cosmos this marriage also failed and he began a relationship with, and eventually married, Ann Druyan, a writer, lecturer, and television/film writer and producer. She was a co-writer on Cosmos and had also been one of the creative directors on the Voyager record project. This third marriage produced a son and a daughter and survived to the end of his life.

In 1995 he was diagnosed with myelodysplasia, a rare disease that often leads to leukaemia, and despite two bone marrow transplants he died as a result of complications from the disease on 20th December 1996.

So why is his a Great Life? When he was awarded the Public Welfare Medal in 1994, the citation read:

“No one has ever succeeded in conveying the wonder, excitement and joy of science as widely as Carl Sagan and few as well.....His ability to capture the imagination of millions and to explain difficult concepts in understandable terms is a magnificent achievement.”

For all his purely scientific works and achievements it's this quality of inspiring communications that makes his an unmistakably Great Life.

EDWARD PELLEW 1ST VISCOUNT OF EXMOUTH


Born, April 1757, a twin he had 4 other siblings. His father, commander of a Dover packet died in 1764. The family returned to their maternal grandparents in Penzance and 10 years later their mother remarried and deserted her children. At 13 years old Edward ran off to sea.

His background gave him no sponsors for a naval career. Boxing Day 1770 he boarded the frigate Juno. He was a strong and energetic boy. Moving the following year to another frigate, Alarm, he was an Able Seaman but by 16 he had risen to the rank of Master’s Mate.

1776 saw war with America. Aboard the Blonde captained by Philemon Pownoll, a large influence on Pellew, they sailed to Canada as part of a convoy of 20 transport ships and troops led by General Burgoyne. He wanted to drive the Americans from Canada and move his troops the 120 miles to Lake Champlain. Pellew was sent with 15 others known as The Lake Service under the command of Lt. John Schank. A shipyard was established 30 miles south east of Montreal but as it was cut off by rapids for the last 12 miles everything had to carried. The ship Inflexible and 2 schooners were dismantled and man handled over the rapids together with 24 pounder guns. Lt. Schank made Pellew his right-hand man and became his lifetime friend. On 9th October the Carlton sailed from St. Johns. Pellew took over as commander after injury to the captain and the death of the first officer. Winter was setting in with harsh conditions with temperatures of -20 degrees. After the hostilities they sailed south. A barge carrying two thirds of their total supplies had been captured. A party of small boats crossed the Hudson and re-captured it but the towing line broke. Pellew dived in with another line, secured it, so it was safely brought back. Unique for a sailor he was commended for gallantry for a battle on land. He returned home to many accolades and was promoted to Lieutenant in 1778.

While he was in Plymouth a brand new frigate anchored, captained by Pownoll. Re-acquainting himself with his old captain, Pellew joined Apollo just before his 23rd birthday. In a squad of 4 frigates they patrolled the English Channel hunting French prizes. On 15th June the ship they were chasing ran for Ostend. Pownoll and Pellew were on deck together when the Stanislaus fired a broadside hitting and killing Pownoll. For the second time in his career Pellew took command. Stanislaus was eventually grounded off Ostend claiming the neutrality of the port under the Dutch. Pellew was devastated at the loss of his friend and patron. Lord Sandwich sympathised with him over Pownoll’s death. He was made a Master and Commander. In the winter of 1782 the American war was over, peace treaties were signed with France and Spain. This peace would last for 10 years. The number of commissioned ships were reduced, captains were sent home on half pay including Pellew.

1783 he married. He was 26 she was 18. They lived in Flushing opposite Falmouth harbour where they had 6 children, his eldest son named Pownoll. During his time at home he became a Burgess, Alderman and a magistrate. Four years later he returned to sea.

He became highly respected as a frigate captain, not only for his sailing prowess but for the way he trained his crew into an efficient fighting force. He was always prepared to do anything that he asked his men to do. Sailors were known not to be swimmers, at least five were rescued by Pellew diving overboard.

1793 French declared war. In June after a bloody battle lasting fifty minutes in which he captured a French ship Pellew was knighted. One of the ships he commanded and which his name would always be associated with was the Indefatigable.

26th January 1796 on the way home for lunch he came across a dis-masted ship below the citadel in Plymouth. The Dutton was carrying 500 troops and families to the West Indies. There was fever on board. Hauling himself out on a rope through a bitter cold sea battered by flotsam Pellew took charge. He organised a lifeline with a cradle to take all off the ship. The rescue lasted well into the night and later Dutton completely broke up. Pelew spent a week in bed recovering. Tributes followed, King George made him a baronet.

Another event which caught the public attention was the defeat, in rough seas, of the Droit de l’Homme. The Times reported on Pellew 32 times, Nelson only 3. Pellew made the equivalent of £3 million pounds from his prizes.

Pellew began to make demands on the Admiralty, mainly to promote his family who were nowhere near his competency. The Admiralty preferred a more diplomatic captain, Nelson. On paper Pellew was promoted but it was more of a punishment. In 1799 the crew was paid off. This time he entered Parliament for Barnstable in 1803. His only speech in the Commons was on the shortages in the Navy but this set up antagonism against him with many influential figures in Parliament and the Admiralty. There was a lot of friction when he was sent to take over the Indies command, ending with a former friend now a rival losing his life at sea. Upset by all that went on Pellew nevertheless returned home a very wealthy man. His next 6 years were as Commander in Chief in the

Mediterranean working with Wellington. At 58 years old he was awarded the Order of the Bath and ennobled as Lord Exmouth of Canonteign.

At home his wife bought West Cliffe House (now called Bicton House) in Teignmouth for her and Pellew and the grand estate of Canonteign where Canonteign House was built for his eldest son.

After 6 months back home Bonaparte escaped and 2 days later Pellew was sent to the Barbary Coast. The Prince Regent had taken up the cause of the Barbary slaves held by the ruler or Day of Algiers. Pellew with much difficulty negotiated the release of 2500 slaves but the British Ambassador was put under house arrest. Five weeks later Pellew returned home to hear that the Dey had imprisoned various British subjects plus 300 seamen from Sicily. Getting a crew to return with him to Algiers proved difficult. Fifty smugglers and 6 poachers, none of whom had been to sea, were sent to his ship. He had 4 weeks to train his motley crew. Commanding a fleet of 21 ships he made them practise firing at targets and to compete with each other. 5 Dutch ships joined them at Gibraltar.

Having made note of the defences at Algiers Pellow made daring plans. He had noted the walls that protected the mole which in turn protected the harbour were high. The Algerians thought them impregnable. Pellew mounted carronades aloft. The Dey ignored a letter to discuss the situation. So Pellew stood on the poop deck and, with his fleet positioned to his orders, he sailed into the most exposed position in the mole. Waiting to be fired on first his crew fired off 3 broadsides in 6 minutes. The walls turned to dust with about 500 defenders killed. There were also many casualties in the fleet. 3 boats were sent into the harbour to set fire to a frigate which spread to the other ships and a warehouse on shore. They returned to the bay at midnight. Next day the Dey capitulated. The Ambassador and 18 seamen who had been taken hostage were released. Later 1000 slaves were also released some of whom had sent 35 years in captivity. Arriving back at Spithead 600 men cheered Pellew who was leaving his ship for the very last time.

Of the previous 46 years he had spent 36 years 3 months 2 weeks and 4 days at sea on a total of 23 ships. The Prince Regent made him a Viscount. Many other countries showered him with honours. He was welcomed back to Teignmouth with parades and celebrations.

Pellew died in January 1833 aged 75 years. His wife refused a London funeral instead he was buried at Christow where the people of Canonteign worshipped.




BRIAN STONEHOUSE, M.B.E.


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