Thomas Harriot and the first moon maps

Thomas Harriot
1560 to July 2nd 1621

First drawing of the moon.

A later drawing via telescope observation.

It is really satisfying to know that some 400 year old drawing has survived relating to the early history of astronomy. These items are truly priceless.

"History Corrected by 400-year-old Moon Map"

January 14th, 2009

space.com

Galileo Galilei is often credited with being the first person to look through a telescope and make drawings of the celestial objects he observed. While the Italian indeed was a pioneer in this realm, he was not the first.

Englishman Thomas Harriot made the first drawing of the moon after looking through a telescope several months before Galileo, in July 1609.

Historian Allan Chapman of the University of Oxford details that 400-year-old breakthrough in astronomy in the February 2009 edition of Astronomy and Geophysics, a journal of the Royal Astronomical Society.

Chapman explains how Harriot preceded Galileo and went on to make other maps of the moon's surface that would not be bettered for decades.

The story

Harriot lived from 1560 to 1621. He studied at St Mary's Hall (now part of Oriel College), Oxford, achieving his BA in 1580.

He then became a mathematical teacher and companion to the explorer Sir Walter Raleigh. In the early 1590s Raleigh fell from royal favor and was imprisoned in the Tower of London. Harriot was passed to the patronage of Henry Percy, the Ninth Earl of Northumberland who was himself imprisoned as one of the Gunpowder Plotters in 1605 but continued to support Harriot in his residence at Sion (now Syon) Park, in what is now west London.

Harriot became a leading force in mathematics, Chapman explains, working on algebraic theory and corresponding with scientists across Europe.

By 1609, Harriot had acquired his first "Dutch trunke" (telescope), which had been invented in The Netherlands in 1608. He turned it on the moon on July 26, becoming the first astronomer to draw an astronomical object after viewing it through a telescope. The crude lunar sketch shows a rough outline of the lunar terminator (the line marking the division between night and day on the moon, as seen from the Earth) and includes a handful of features like the dark areas Mare Crisium, Mare Tranquilitatis and Mare Foecunditatis.

Harriot went on to produce more maps from 1610 to 1613, Chapman said in a statement released today. Not all of these are dated, but they show an increasing level of detail. By 1613 he had created two maps of the whole moon, with many identifiable features such as lunar craters that crucially are depicted in their correct relative positions.

The earliest telescopes of the kind used by Harriot (and Galileo) had a narrow field of view, meaning that only a small portion of the moon could be seen at any one time and making this work all the more impressive. No better maps would be published for several decades.

Cush job

Despite his innovative work, Harriot remains relatively unknown. Unlike Galileo, he did not publish his drawings. Unlike Galileo, Harriot is not being widely celebrated during 2009, dubbed the International Year of Astronomy as a commemoration of the telescope's 400th year.

Chapman attributes this to his comfortable position as a "well-maintained philosopher to a great and wealthy nobleman" with a generous salary, said to be "several times the level of the Warden of Wadham College, Oxford." Harriot had comfortable housing and a specially provided observing chamber on top of Sion House, all of which contrasted with Galileo's financial pressures.

Galileo, interestingly, was unable to buy a telescope. So he figured out the optics of it and built his own. He also examined the moon, and then found that the Milky Way was composed of individual stars. Galileo also discovered four moons around Jupiter and spent much time observing and drawing sunspots.

"Thomas Harriot is an unsung hero of science," Chapman said. "His drawings mark the beginning of the era of modern astronomy we now live in, where telescopes large and small give us extraordinary information about the universe we inhabit."

Professor Andy Fabian, President of the Royal Astronomical Society, agrees.

"As an astrophysicist of the 21st century, I can only look back and marvel at the work of 17th century astronomers like Thomas Harriot," Fabian said. "The world is right to celebrate Galileo in the International Year of Astronomy – but Harriot shouldn't be forgotten!"

Thomas Harriot

Double star observations--Galileo Galilei

Galileo Galilei Demonstrates His Astronomical Theories to a Monk

This is somewhat unusual...that earlier observations of double stars negated the conclusions written in Galileo Galilei's Dialogue Concerning the Two Chief World Systems [1632]...such is the hypothesis in Christopher M. Graney's "Regarding the Potential Impact of Double Star Observations on Conceptions of the Universe of Stars in the Early 17th Century".

ABSTRACT:

Galileo Galilei believed that stars were distant suns whose sizes measured via his telescope were a direct indication of distance -- fainter stars (appearing smaller in the telescope) being farther away than brighter ones. Galileo argued in his Dialogue that telescopic observation of a chance alignment of a faint (distant) and bright (closer) star would reveal annual parallax, if such double stars were found. This would provide support both for Galileo's ideas concerning the nature of stars and for the motion of the Earth. However, Galileo actually made observations of such double stars, well before publication of the Dialogue. We show that the results of these observations, and the likely results of observations of any double star that was a viable subject for Galileo's telescope, would undermine Galileo's ideas, not support them. We argue that such observations would lead either to the more correct idea that stars were sun-like bodies of varying sizes which could be physically grouped, or to the less correct idea that stars are not sun-like bodies, and even to the idea that the Earth did not move.

REGARDING THE POTENTIAL IMPACT OF DOUBLE STAR OBSERVATIONS ON CONCEPTIONS OF THE UNIVERSE OF STARS IN THE EARLY 17TH CENTURY


Signores Salviati, Sagrfdo, and Simplicio--cosmology debate by Galileo

Signores Salviati, Sagrfdo, and Simplicio--cosmology debate by Galileo

Galileo Galilei

This is wonderful material written by Galileo Galilei in the Socratic style--including the traditional "strawman". It concerns the Ptolemaic vs the Copemican systems and a revolutionary cosmological shift to a more scientific approach to an understanding of the universe.

"Yesterday we resolved to meet today and discuss as clearly and in as much detail as possible the character and the efficacy of those laws of nature which up to the present have been put forth by the partisans of the Aristotelian and Ptolemaic position on the one hand, and by the followers of the Copemican system on the other."

The players are Salviati, Sagrfdo, and Simplicio.

"Dialogue Concerning the Two Chief World Systems"

by

Galileo Galilei

Translated by Stillman Drake

Annotated And Condensed by S. E. Sciortino

Copyright Dartmouth College 1999

TO THE DISCERNING READER

Several years ago there was published in Rome a salutary edict which, in order to obviaie the dangerous tendencies of our present age, imposed a seasonable silence upon the Pythagorean opinion that the earth moves There were those who impudently asserted that this decree had its origin not injudicious inquire, but in passion none too well informed Complaints were to be heard that advisers who were totally unskilled at astronomical observations ought not to clip the wings of reflective intellects by means of rash prohibitions.

Upon hearing such carping insolence, my eal could not be contained Being thoroughly informed about that prudent determination, I decided to appear openly in the theater of the world as a witness of the sober truth. I was at that time in Rome; I was not only received by the most eminent prelates of that Court, but had their applause; indeed this decree was not published without some previous notice of it having been given to me. Therefore I propose in the present work to show to foreign nations that as much is understood of this matter in Italy, and pariicularly in Rome, as transalpine diligence can ever have imagined Collecting all the reflections thai properly concern the Copernican system, I shall make it known that everything was brought before the attention of the Roman censorship, and that there proceed from this clime not only dogmas for the welfare of the soul, but ingenious discoveries for the delight of the mind as well.

To this end I have taken the Copernican side in the disco urse, proceeding as with a pure mathematical hypothesis and striving by every artipee to represent it as superior to supposing the earth motionless–not, indeed absolutely, but as against the arguments of some professed Peripatetics. (note 1) These men indeed deserve not even that name, for they do not walk about; they are content to adore the shadows, philosophizing not with due circumspection but merely from having memorized a fow ill-understood principles.

Three principal headings are treated First, I shall try to show that all experiments practicable upon the earth are inszyfficient measures for proving its mobility, since they are indiferently adaptable to an earth in motion or at rest. I hope in so doing to reveal many observations unknown to the ancients. Secondly, the celestial phenomena will be examined strengthening the Copernican hypothesis until it might seem that this must triumph absolutely. Here new reflections are adjoined which might be used in order to simplfy astronomy, though not because of any necess ire importeded by nature. In the third place, I shall propose an ingenious speculation. It happens that long ago I said that the unsolved problem of the ocean tides might receive some light from assuming the motion of the earth. This assertion of mine, passing by word of mouth, found loving fathers who adopted it as a child of their own ingenuity. Now, so that no stranger may ever a who, arming himself with our weapons, shall charge us with want of attention to such an important matter, I have thought it good to reveal those probabilities which might render this plausible, given that the earth moves.

I hope that from these considerations the world will come to know that if other nations have navigated more, we have not theorized less. It is not from failing to take count of what others have thought that we have yielded to asserting that the earth is motionless, and holding the contrary to be a mere mathematical caprice, but (if for nothing else) for those reasons that are supplied by piety, religion, the knowledge of Divine Omnipotence, and a consciousness of the limitations of the human mind I have thought it most appropriate to explain these concepts in the form of dialogues, which, no! being restricted to the rigorous observance of mathematical laws, make room also for digressions which are sometimes no less interesting than the principal argument.

Many years ago I was often to be found in the marvelous city of Venice, in discussions with Signore Giovanni Francesco Sagredo, a man of noble extraction and trenchant wit. Prom Florence came Signore Filippo Salviati, the least of whose glories were the eminence of his blbod and the magnfficence of his fortune. His was a sublime intellect which fed no more hungrily upon any pleasure than it did upon fine meditations. I often talked with these two of such matters in the presence of a certain Peripatetic philosopher whose greatest obstacle in apprehending the truth seemed to be the reputation he had acquired by his interpretations of Aristotle. (note 2)

Now, since bitter death has deprived Venice and Florence of those two great luminaries in the very meridian of their years, I have resolved to make their fame live on in these pages, so far as my poor abilities will permit, by introducing them as interlocutors in the present argument. (Nor shall the good Peripatetic lack a place; because of his excessive affection toward the Commentaries of Simplicius, (note 3) I have thought fit to leave him under the name of the author he so much revered, without mentioning his own) May it please those two great souls, ever venerable to my heart, to accept this public monument of my undying love. And may the memory of their eloquence assist me in delivering to posterity the promised reflections.

It happened that several discussions had taken place casually at various times among these gentlemen, and had rather whetted than satisfied their thirst for learning. Hence very wisely they resolved to meet together on certain days during which, setting aside all other business, they might apply themselves more methodically to the contemplation ofthe wonders of God in the heavens and upon the earth. They met in the palace of the illustrious Sagredo; and, after the customary but brief exchange of compliments, Saiviati commenced as follows.

note 1--i.e. Aristoteleans: literally "those who walk around." Aristotle used to walk about the Lyceum.

note 2--Sagredo was, in fact, a close friend of Galileo, and represents in the dialogue the neutral position of an open-minded man of letters: Salviati is the man of science, Galileo himself; the philosopher, who will be called Simplicio is a fictitious, a straw man. steeped in Aristotelian philosophy.

note 3--Simplicius wrote a sixth century commentary on Aristotle.


Galileo dialogue--Part I

Galileo dialogue--Part II

Galileo dialogue--Part III

Galileo Galilei...revolutionary

Galileo Galilei
1564-1642

Bye, bye Ptolemy...the great Galileo Galilei.

The Galileo Project