Tag Archives: Astronomy

November 11, 1572

Tycho Brahe

On this date, the Danish nobleman, astrologer, and alchemist Tycho Brahe observed (from Herrevad Abbey) a very bright star, now named SN 1572, that had unexpectedly appeared in the constellation Cassiopeia.  Since it had been maintained since antiquity that the world beyond the orbit of the moon, i.e., the world of the fixed stars, was eternal and unchangeable (a fundamental axiom, known as “celestial immutability”, of the Aristotelian world view), other observers held that the phenomenon was something in the Earth’s atmosphere.  Tycho, however, noticed that the parallax of the object did not change from night to night, suggesting that the object was far away.  He argued that a nearby object should appear to shift its position with respect to the background.  Tycho published a small book, De Stella Nova (1573), thereby coining the term nova for a “new” star (we now know that Tycho’s star in Cassiopeia was a supernova 7500 light years from Earth).  He knew the cosmological ramifications of his discovery and was strongly critical of those who dismissed the implications of the astronomical appearance, writing in the preface to De Stella Nova: “O crassa ingenia. O caecos coeli spectatores” (“Oh thick wits.  Oh blind watchers of the sky”).

August 25, 1835 (a Tuesday)

On this date, the the first in a series of six articles announcing the supposed discovery of life on the moon appeared in the New York Sun newspaper (subsequent installments appeared on August 26, 27, 28, 29, and 31). It bore the headline:

GREAT ASTRONOMICAL DISCOVERIES
LATELY MADE
BY SIR JOHN HERSCHEL, L.L.D. F.R.S. &c.
At the Cape of Good Hope
[From Supplement to the Edinburgh Journal of Science]

"A View of the Inhabitants of the Moon" Illustration from an 1836 English pamphlet, publisher unknown. Note the biped beavers on the right.

The article began by triumphantly listing a series of stunning astronomical breakthroughs that the famous British astronomer, Sir John Herschel, had apparently made “by means of a telescope of vast dimensions and an entirely new principle.” Herschel, the article declared, had established a “new theory of cometary phenomena”; he had discovered planets in other solar systems; and he had “solved or corrected nearly every leading problem of mathematical astronomy.” Then, almost as if it were an afterthought, the article revealed Herschel’s final, stunning achievement: he had discovered life on the moon!

The article continued on and offered an elaborate account of the fantastic sights viewed by Herschel during his telescopic observation of the moon. It described a lunar topography that included vast forests, inland seas, and lilac-hued quartz pyramids. Readers learned that herds of bison wandered across the plains of the moon; that blue unicorns perched on its hilltops; and that spherical, amphibious creatures rolled across its beaches. The highpoint of the narrative came when it revealed that Herschel had found evidence of intelligent life on the moon: he had discovered both a primitive tribe of hut-dwelling, fire-wielding biped beavers, and a race of winged humans living in pastoral harmony around a mysterious, golden-roofed temple. Herschel dubbed these latter creatures the Vespertilio-homo, or “man-bat”.

1835 lithograph of the lunar "Ruby Amphitheater" and moon men, described in the New York Sun's moon hoax.

The article, of course, was an elaborate hoax. Herschel had in fact traveled to Capetown, South Africa, in January 1834 to set up an observatory with a powerful new telescope. But Herschel had not really observed life on the moon, nor had he accomplished any of the other astronomical breakthroughs credited to him in the article. In fact, Herschel was not even aware until much later that such discoveries had been attributed to him. Furthermore, the Edinburgh Journal of Science had stopped publication years earlier, and Grant was a fictional character. However, the New York Sun managed to sell thousands of copies of the article before the public realized that it had been hoaxed.

The articles were most likely written by Richard Adams Locke, a Sun reporter educated at Cambridge University. Intended as satire, they were designed to poke fun at earlier, serious speculations about extraterrestrial life, particularly those of Reverend Thomas Dick, a popular science writer who claimed in his bestselling books that the moon alone had 4.2 billion inhabitants.

However, Locke never publicly admitted to being the author of the hoax, and rumors have persisted that others were also involved in the production of the story. Two men in particular have been mentioned in connection with the hoax: Jean-Nicolas Nicollet, a French astronomer who was travelling through America at the time (though he was in Mississippi, not New York, when the moon hoax appeared), and Lewis Gaylord Clark, editor of the Knickerbocker Magazine. However, there is no real evidence to suggest that anyone but Locke was the author of the hoax.

“New Inhabitants of the Moon” from Delle Scoperte Fatte Nella Luna del Dottor Giovanni Herschel, Napoli, 1836 (Italian edition of the Moon Hoax).

Readers were completely taken in by the story, however, and failed to recognize it as satire. The craze over Herschel’s supposed discoveries even fooled a committee of Yale University scientists, who traveled to New York in search of the Edinburgh Journal articles. After Sun employees sent them back and forth between the printing and editorial offices, hoping to discourage them, the scientists returned to New Haven without realizing they had been tricked.

Despite the intense public speculation about the moon story, the Sun never publicly conceded that it was a hoax. On September 16, 1835 the Sun did publish a column in which it discussed the possibility that the story was a hoax, but it never confessed to anything. Quite the contrary. It wrote that, “Certain correspondents have been urging us to come out and confess the whole to be a hoax; but this we can by no means do, until we have the testimony of the English or Scotch papers to corroborate such a declaration.” This is the closest the Sun ever came to an admission of guilt.

People were generally amused by the whole thing, and sales of the paper didn’t suffer.

References:

  • Michael J. Crowe. The Extraterrestrial Life Debate, 1750-1900. (Cambridge University Press, 1986) pp. 202-15.
  • David S. Evans. “The Great Moon Hoax.” Sky and Telescope. September, 1981 (196-198); October, 1981 (308-311).
  • William N. Griggs (ed.). The Celebrated “Moon Story,” its origin and incidents; with a memoir of the author, and an appendix containing, I. An Authentic description of the moon; II. A New Theory of the Lunar Surface, in relation to that of the earth. (New York, 1852).
  • Frank M. O’Brien. The Story of The Sun. (New York: D. Appleton and Company, 1928). Chapters 1-6.
  • Edgar Allan Poe. “Richard Adams Locke,” from “The Literati of New York City No.VI,” October 1846, Godey’s Lady’s Book, pp.159-162.
  • Gibson Reaves. “The Great Moon Hoax of 1835.” The Griffith Observer. November, 1954. Vol. XVII, No. 11, pp. 126-134.
  • Ormond Seavey (ed.). The Moon Hoax, Or, A Discovery That The Moon Has A Vast Population of Human Beings. (Boston: Gregg Press, 1975).

August 25, 1609 (a Tuesday)

Bell Tower in St. Mark’s Square

On this date, the Italian mathematician Galileo Galilei marched the Doge of Venice (Leonardo Donato), his counsellor, the Chiefs of the Council of Ten, and the Sages of the Order, who commanded the Venetian navy, up the Bell Tower (Campanile) in St. Mark’s Square in Venice, Italy. Once at the top, Galileo showed them views of distant cities, ships on the horizon, and parishioners entering a church on the island of Murano – all of which had been invisible to the eye alone – with the aid of his first telescope. The Doge was awestruck. The military had a powerful new secret weapon. Venice was confirmed again as a triumph. Galileo presented the Doge with the telescope on his knees and received a doubled salary, a lifetime appointment, and a bonus amounting to a year’s wages.

Throughout the the rest of 1609, particularly during the winter, Galileo made many astronomical studies. On January 7, 1610 Galileo observed with his telescope what he described at the time as “three fixed stars, totally invisible by their smallness,” all close to Jupiter, and lying on a straight line through it. Observations on subsequent nights showed that the positions of these “stars” relative to Jupiter were changing in a way that would have been inexplicable if they had really been fixed stars. On January 10 Galileo noted that one of them had disappeared, an observation which he attributed to its being hidden behind Jupiter. Within a few days he concluded that they were orbiting Jupiter. He had discovered three of Jupiter’s four largest satellites (moons): Io, Europa, and Callisto. He discovered the fourth, Ganymede, on January 13. Galileo named the four satellites he had discovered Medicean stars, in honor of his future patron, Cosimo II de’ Medici, Grand Duke of Tuscany, and Cosimo’s three brothers. [Later astronomers, however, renamed them the Galilean satellites in honor of Galileo himself.] On March 12, 1610 Galileo published the results of his studies in a brief treatise entitled Sidereus Nuncius (Starry Messenger).

These observations over a six night period, from January 7 through January 13, provided a view to Galileo that revealed that perhaps not everything orbited the Earth (geocentric model), as Ptolemy as well as the Catholic Church had adopted. And, if these small, but bright points of light went around Jupiter and not the Earth, perhaps there were other objects that did not orbit the Earth. His findings allowed him to confirm the Sun-centered theory of Copernicus. This short period of time from the summer of 1609 through to March of 1610, when Siderius Nuncius was published, had a revolutionary impact on astronomy almost overnight and it catapulted Galileo into the scientific spotlight and into the fire and wrath of the Catholic Church.

The Catholic Church condemned Galileo for his theories on June 22, 1633. He was forced to disown them and to live on his own for the rest of his life. In the following century the Vatican began changing its attitude. A mausoleum was built in 1734 to honor him. In 1822 Pope Pius VII gave permission for Galileo’s theory to be taught in schools. In 1968 Pope Paul VI had the trial against Galileo reassessed, then Pope John Paul II took the final step in the Church’s rehabilitation of the scientist in 1984 when he formally acknowledged that the Catholic Church had erred when it condemned the Italian astronomer for maintaining that Earth revolved around the Sun.

August 6, 1996 (a Tuesday)

The ALH84001 Meteorite

On this date, NASA Administrator Daniel Goldin announced the discovery of evidence of a primitive bacterial life form on Mars. The evidence came from a tiny putative fossil found on a meteorite in Antarctica thought to have come from Mars billions of years ago. The meteorite, called ALH84001, was found in 1984 in Allan Hills ice field, Antarctica, by an annual expedition of the National Science Foundation’s Antarctic Meteorite Program. It was preserved for study in JSC’s Meteorite Processing Laboratory and its possible Martian origin was not recognized until 1993.

The indication of life hinges on three important pieces of evidence, all discovered within mineralized fractures in the meteorite in close proximity to each other:

  1. hydrocarbons which are the same as breakdown products of dead microorganisms on Earth,
  2. mineral phases consistent with by-products of bacterial activity, and
  3. tiny carbonate globules which may be microfossils of the primitive bacteria.

Based on age dating of the meteorite, the following scenario has been proposed:

  1. The original igneous rock solidified within Mars about 4.5 billion years ago, about 100 million years after the formation of the planet (based on isotope ages of the igneous component of the meteorite).
  2. Between 3.6 and 4 billion years ago the rock was fractured, presumably by meteorite impacts. Water then permeated the cracks, depositing carbonate minerals and allowing primitive bacteria to live in the fractures.
  3. About 3.6 billion years ago, the bacteria and their by-products became fossilized in the fractures (based on isotope ages of the minerals in the fractures).
  4. 16 million years ago, a large meteorite struck Mars, dislodging a large chunk of this rock and ejecting it into space (based on the cosmic ray exposure age of the meteorite).
  5. 13,000 years ago, the meteorite landed in Antarctica.
  6. The meteorite, ALH84001, was discovered in 1984 in the Allan Hills region of Antarctica.

References:

  • S. McKay, E. K. Gibson Jr., K. L. Thomas-Keprta, H. Vali, C. S. Romanek, S. J. Clemett, X. D. F. Chillier, C. R. Maechling and R. N. Zare. “Search for past life on Mars: Possible relic biogenic activity in Martian meteorite ALH84001D, Science 273 (5277): 924-930 (16 August 1996).

June 30, 1908 (Julian calendar/old style: a Tuesday)

The above picture was taken by a Russian expedition to the Tunguska site in 1927, finding trees littering the ground like toothpicks.

On this date, a large rocky asteroid or perhaps an icy comet entered the atmosphere traveling at an estimated speed of about 33,500 miles per hour and then detonated in the sky near the Podkamennaya Tunguska (Stony Tunguska) River in remote Siberia, Russia (60° 54′ 59″ N, 101° 57′ 0″ E). During its quick plunge, the 220-million-pound space asteroid/comet heated the air surrounding it to 44,500 degrees Fahrenheit. At 7:14:28 AM (local Siberia time), at a height of about 28,000 feet, the combination of pressure and heat caused the asteroid/comet to fragment and annihilate itself, producing a fireball and releasing energy equivalent to about 185 Hiroshima bombs. The aerial explosion explains why there was no impact crater – the great majority of the cosmic object was consumed in the explosion.

Reconstruction of the Tunguska Event. (William K. Hartmann)

The massive explosion packed a wallop. The resulting seismic shockwave registered with sensitive barometers as far away as England. Dense clouds formed over the region at high altitudes which reflected sunlight from beyond the horizon. As a result, night skies glowed, and reports came in that people who lived as far away as Asia could read newspapers outdoors as late as midnight. Recent studies of so-called night-shining clouds sometimes linked to space shuttle launches suggest that it was, in fact, a comet that caused Tunguska.

Locally, hundreds of reindeer, the livelihood of local herders, were killed, but there was no direct evidence that any person perished in the blast. Locals believed the blast was a visitation by the god Ogdy, who had cursed the area by smashing trees and killing animals.

Due to the remoteness of the blast and the chaotic conditions prevailing inside Russia at the time, the first scientific expedition to the area would have to wait for 19 years. In 1921, Leonid Kulik, the chief curator for the meteorite collection of the St. Petersburg museum, led an expedition to Tunguska. But the harsh conditions of the Siberian outback thwarted his team’s attempt to reach the area of the blast. In 1927, a new expedition, again lead by Kulik, reached its goal.
____________________________________________________

This is rare, raw footage from the 1921 Tunguska expedition as well as modern day footage showing the aftermath of the huge Tunguska explosion in 1908.
____________________________________________________
While testimonials may have at first been difficult to obtain, there was plenty of evidence lying around. Eight hundred square miles of remote forest had been ripped asunder. Eighty million trees lying on their sides in a radial pattern acted as markers, pointing directly away from the blast’s hypocenter. When the team arrived at ground zero, they found the trees there standing upright – but their limbs and bark had been stripped away. They looked like a forest of telephone poles.

Tunguska Event location (click for larger image).

Such “debranching” requires fast moving shock waves that break off a tree’s branches before the branches can transfer the impact momentum to the tree’s stem. Thirty seven years after the Tunguska Event, branchless trees would be found at the site of another massive explosion – Hiroshima, Japan.

References:

June 22, 1633 (a Wednesday)

Galileo

On this date, the Florentine-Italian astronomer Galileo Galilei was compelled by the Roman Inquisition to recant the theory he held that  Earth travels around the sun.

June 21: 4,599,997,988 B.C.E.

The image above shows an example of what happens during the June solstice. Illustration is not to scale

On this date (approximately), the first June solstice occurred on Earth. It has happened with each revolution of the Earth around the Sun since then.

The solstice happens at the same instant for all of us, everywhere on Earth. To find the time of the solstice in your location, you have to translate to your time zone.

The June solstice occurs because Earth doesn’t orbit the Sun upright. Instead, our world is tilted on its axis by 23-and-a-half degrees, and as a result, Earth’s Northern and Southern Hemispheres trade places in receiving the sun’s light and warmth most directly. If the Earth’s rotation was at right angles to the plane of its orbit around the sun, there would be no solstice days and no seasons.

At the June solstice, Earth is positioned in its orbit so that our world’s North Pole is leaning most toward the sun. As seen from Earth, the sun is directly overhead at noon 23 1/2 degrees north of the equator, at an imaginary line encircling the globe known as the Tropic of Cancer – named after the constellation Cancer the Crab. This is as far north as the sun ever gets.

All locations north of the equator have days longer than 12 hours at the June solstice. Meanwhile, all locations south of the equator have days shorter than 12 hours.

The varying dates of the solstice are mainly due to the calendar system – most western countries use the Gregorian calendar, which has 365 days in a year, or 366 days in a leap year. As for the tropical year, it is approximately 365.242199 days, but varies from year to year because of the influence of other planets. A tropical year is the length of time that the sun takes to return to the same position in the cycle of seasons, as seen from Earth. The exact orbital and daily rotational motion of the Earth, such as the “wobble” in the Earth’s axis (precession), also contributes to the changing solstice dates.

Sunrise over Stonehenge on the summer solstice, 21 June 2005.

For us in the modern world, the solstice is a time to recall the reverence and understanding that early people had for the sky. Some 5,000 years ago, people placed huge stones in a circle on a broad plain in what’s now England and aligned them with the June solstice sunrise.

We may never comprehend the full significance of Stonehenge. But we do know that knowledge of this sort wasn’t isolated to just one part of the world. Around the same time Stonehenge was being constructed in England, two great pyramids and then the Sphinx were built on Egyptian sands. If you stood at the Sphinx on the summer solstice and gazed toward the two pyramids, you’d see the sun set exactly between them.

Cultures universally have had markers, holidays, and alignments – all related to the solstice. It has been universal among humans to treasure this time of warmth and light.

June 14, 1822 (a Friday)

Photo of the 1832 Fragment of a Difference Engine

On this date, British mathematician and philosopher Charles Babbage announced completion of his first “difference engine” in a paper entitled Note on the application of machinery to the computation of astronomical and mathematical tables read to the Royal Astronomical Society. Difference engines are strictly calculators. They crunch numbers the only way they know how – by repeated addition according to the method of finite differences. Babbage had embarked on an ambitious venture to design and build mechanical “computers” (a term in those days that referred to humans employed to perform calculations by hand) – vast machines of unprecedented size and intricacy – to eliminate the risk of human error.

On 13 July 1823, Babbage received a gold medal from the Astronomical Society for his development of the difference engine. He then met the Chancellor of the Exchequer to seek public funds for the construction of a large difference engine. His initial grant was for £1500 and he began work on a large difference engine which he believed he could complete in three years.

In 1834, work on the difference engine stopped because the government could not decide whether to continue to fund the project; eight years later, in 1842, it finally decided not to proceed.

By 1834 Babbage’s work on the difference engine had led him to a much more sophisticated idea; he had completed the first drawings of the “analytical engine”. The Analytical Engine is much more than a calculator and marks the progression from the mechanized arithmetic of calculation to fully-fledged general-purpose computation – the forerunner of the modern electronic computer. Although the analytic engine never progressed beyond detailed drawings, it is remarkably similar in logical components to a present day computer.

Babbage ultimately failed to build a complete machine despite independent wealth, social position, government funding, a decade of design and development, and the best of British engineering. The reasons are still debated and the cocktail of considerations is a rich one. Babbage was a prickly character, highly principled, easily offended and given to virulent public criticism of those he took to be his enemies. Runaway costs, high precision, a disastrous dispute with his engineer, fitful financing, political instability, accusations of personal vendettas, delays, failing credibility and the cultural divide between pure and applied science, were all factors.

[My favorite Babbage quote – Ed.:]

The whole of the developments and operations of analysis are now capable of being executed by machinery. … As soon as an Analytical Engine exists, it will necessarily guide the future course of the science.

Passages from the Life of a Philosopher, ch. 8 “Of the Analytical Engine” (London 1864)

May 28, 585 B.C.E.

A Total Solar Eclipse over Turkey

On this date, the Battle of Halys, also known as the Battle of the Eclipse, took place at the Halys River (present-day “Kızılırmak” river in Turkey) between the Medes and the Lydians. The final battle of a fifteen-year war between Alyattes II of Lydia and Cyaxares of the Medes, the battle ended abruptly due to a total solar eclipse. The eclipse was perceived as an omen, indicating that the gods wanted the fighting to stop. Since the exact dates of eclipses can be calculated, the Battle of the Halys is the earliest historical event of which the date is known with such precision.  (This date is based on the proleptic Julian calendar.)

According to Herodotus (Histories, 1.74):

In the sixth year a battle took place in which it happened, when the fight had begun, that suddenly the day became night. And this change of the day Thales the Milesian had foretold to the Ionians laying down as a limit this very year in which the change took place. The Lydians however and the Medes, when they saw that it had become night instead of day, ceased from their fighting and were much more eager both of them that peace should be made between them.

References:

  • Herodotus, translated by Robin Waterfield, (1998). The Histories. New York: Oxford University Press.

May 18, 1910 (a Wednesday)

On this date, thousands of people took to their roofs, huddling for comfort and praying for salvation. Many believed the end of the world was near. The source of their anxiety was the return of Halley’s Comet from its 75-year odyssey through space.

Comet Halley

Many scientists were excited by the opportunity to increase the knowledge of astronomy. By late 1909, several of the world’s major observatories had geared up for Halley’s appearance. The public, too, eagerly awaited the moment when the comet became visible to the naked eye. Scientists had calculated it would appear between May 18 and 19, predicting that Halley’s tail would possibly sweep across Earth.

The tabloids jumped in, and discussed the catastrophic effects of the gaseous comet on the Earth’s atmosphere, causing many to panic. Despite a number of previous documented appearances having caused no deaths, the 1910 return of Halley’s Comet was widely perceived as a threat to mankind, allegedly due to noxious vapors emanating from its tail. This may be the first apocalyptic panic founded on a scientific, rather than religious misapprehension. In actual fact, the tail of Halley’s Comet never came any closer than 400,000 km to the Earth’s surface, and would not have been harmful at any distance.

May 14, 1864 (a Saturday)

A fragment of the Orgueil meteorite.

On this date, a carbonaceous chondrite disintegrated and fell in fragments near the French town of Orgueil. One specimen was immediately examined by the French scientist S. Cloëz, who commented that its content “would seem to indicate the existence of organized substances in celestial bodies.” Subsequently, several eminent chemists of the time, including Gabriel-Auguste Dubrée and Marcellin Berthelot, analyzed samples and confirmed the existence of organic materials in the rock. However, hopes of discovering actual living matter in the meteorite were dashed by the experiments of Louis Pasteur, as recounted by Carl Sagan:

[He] caused a special drill to be constructed, which, he hoped, would remove samples from the interior of the meteorite without contaminating them with microorganisms from outside. Using sterile techniques, Pasteur inoculated an organic medium to search for growth of any indigenous microorganisms which the meteorite interior might contain. The results were negative, and have relevance today: Pasteur extracted his sample shortly after the fall of the meteorite, and was, of course, a very careful experimentalist.

A fragment of the Ivuna meteorite (Tanzania, Africa, 1938).

Virtually all meteorites scientists have studied are former parts of asteroids. However, recent determination of the amino acid signatures within the Orgueil meteorite and Ivuna meteorite suggest that these compounds were likely synthesized from components such as hydrogen cyanide, which have been recently observed in the comets Hale-Bopp and Hyakutake. This suggests that the organic material in Orgueil and Ivuna is the product of reactions that once took place in the nucleus of a comet, which, if true, would make these meteorites the first to be identified as having come from a cometary nucleus. This would add to the evidence that the amino acids that helped generate life on Earth may have been delivered by meteorites that were derived from the remnants of comets.

April 15, 1857 (a Wednesday)

On this date, a 3-kg carbonaceous chondrite fell at Kaba, near Debrecen, Hungary. The arrival of this meteorite was described as follows in the book The Geologist (1859) by Samuel Joseph Mackie (pp. 285-6):

About 10 pm an inhabitant of Kaba, sleeping in the open air, was awakened by a noise, different from that of thunder, as he described it, and perceived in the serene sky a luminous globe, of dazzling brightness, following a parabolic course during four seconds. This phenomenon was observed by several inhabitants of the same place. As one of them was riding out the next morning, his horse was frightened by the sight of a black stone, deeply bedded in the soil of the road, the ground around it being depressed and creviced. When dug out the meteorite weighed about 7 pounds. The finder broke off some fragments, and the remainder, weighing 5-1/4 lbs., was deposited in the Museum of the Reformed College at Debreczin.

Samples of the Kaba meteorite and the Cold Bokkeveld meteorite were examined and found to contain organic substances by Friedrich Wöhler, who inferred a biological origin. Ironically, it was Wöhler who had shown that it was possible to make organic chemicals by inorganic means. However, it was only later appreciated that complex carbon molecules can be manufactured in space by purely chemical processes.

April 15, 1452

Leonardo's self portrait

On this date, Leonardo da Vinci was born at Anchiano near Vinci in the Florence area of Italy. It is well known that in one of his unpublished notebooks, Leonardo concluded that some fossil sea shells were the remains of shellfish.

Although “fossil” is now a common and widely used word, whose meaning is known to practically everyone, the general acceptance of the idea that fossils are the remains of ancient organisms required millennia to achieve. One reason for this is that the great age of Earth also was not widely appreciated until relatively recently. Without an Earth eons old the idea of ancient life and the idea of fossils are meaningless.

The use of fossils in understanding the distant past can be traced back to at least the sixth century B.C.E., when Xenophanes of Colophon lived. Xenophanes described the occurrence of clam shells in rocks outcropping in mountainous parts of Attica. He recognized that these lithified clam shells were closely similar to clams that were then living along the coastline of the Aegean Sea. To account for the occurrence of these lithified clam shells far from the present sea, he argued that they were the preserved remains of clams that had lived at an earlier time when Attica was covered by an ocean. Hippolytus of Rome (c. 170 – c. 236) in his Refutation of all Heresies (1.14.5-6) records that Xenophanes studied the fossils to be found in quarries:

Xenophanes declared that the sea is salty because many mixtures flow together in it… He believes that earth is being mixed into the sea and over time it is being dissolved by the moisture, saying that he has the following kind of proofs, that sea shells are found in the middle of the earth and in mountains, and the impressions of a fish and seals have been found at Syracuse in the quarries, and the impression of a laurel leaf in the depth of the stone in Paros, and on Malta flat shapes of all marine life. He says that these things occurred when all things were covered with mud long ago and the impressions were dried in the mud.

However, in 750 BCE there were no quantitative methods for verifying this hypothesis, and so Xenophanes’ rather modern-sounding explanation for these clams could not be tested, and disappeared from view. This interpretation of fossils did not reappear in history until Leonardo da Vinci, although he did not contribute to the understanding of fossils since his views were never published.

March 15, 1806 (a Saturday)

The Alais meteorite.

The Alais meteorite.

On this date, a 6-kg carbonaceous chondrite – a type of meteorite carrying carbon-based, organic chemicals – was unequivocally identified for the first time. Its arrival on Earth was noted at 5:30 pm, outside Alais, France. The organic chemicals it carried suggested the possibility of life on whatever body was the source, somewhere in the universe. According to the observations of the Swedish chemist Jöns Jakob Berzelius and a commission appointed by the French Academy of Sciences, it “emits a faint bituminous substance” when heated. Berzelius analyzed the Alais meteorite and reported in 1833 that destructive distillation yielded a blackish substance, indigenous water, carbon dioxide gas, a soluble salt containing ammonia, and a blackish-brown sublimate, which Berzelius confessed was unknown to him.

March 5, 1616 (a Saturday)

Cardinal Robert Bellarmine

On this date, the Copernican theory was declared “false and erroneous” by the Decree of the Holy Congregation of the Most Illustrious Lord Cardinals in charge of the Index (more commonly known as the Decree of the Index) written by Cardinal Robert Bellarmine, and issued by the Catholic Church in Rome. Further, no person was to be permitted to hold or teach the theory that the Earth revolves around the sun. When Galileo subsequently violated the decree, he was put on trial and held under house arrest for the final eight years of his life.

February 17, 1600 (a Thursday)

The statue of Bruno in the place where he was executed.

On this date, the Italian philosopher and Dominican friar Giordano Bruno was brought to the Campo de’ Fiori, a central Roman market square. His tongue in a gag, tied to a pole naked, Bruno was burned at the stake as a heretic.

The Fraternity of St. John the Beheaded recounted Bruno’s burning in this account which is considered authoritative by the Catholic Church:

But he insisted till the end always in his damned refractoriness and twisted brain and his mind with a thousand errors; yes, he didn’t give up his stubborness, not even when the court ushers took him away to the Campo de’ Fiori. There his clothes were taken off, he was bound to a stake and burned alive [e quivi spogliato nudo e legato a un palo fu brusciato vivo]. In all this time he was accompanied by our fraternity, who sang constant litanies, while the comforters tried till the last moment to break his stubborn resistance, till he gave up a miserable and pitiable life.

Bruno’s execution followed his lengthy imprisonment and trial that had begun on 27 January 1593 under the Roman Inquisition.

Bruno was born at Nola, near Naples, in 1548. Originally named Filippo, he took the name Giordano when he joined the Dominicans, who trained him in Aristotelian philosophy and Thomistic theology. Independent in thinking and tempestuous in personality, he fled the order in 1576 to avoid a trial on doctrinal charges and began the wandering that characterized his life.

In his book De l’Infinito, Universo e Mondi (On the Infinite Universe and Worlds), which was published in 1584, Bruno argued that the universe was infinite, that it contained an infinite number of worlds, and that these are all inhabited by intelligent beings:

Innumerable suns exist; innumerable earths revolve around these suns in a manner similar to the way the seven planets revolve around our sun. Living beings inhabit these worlds.

In Cena de le Ceneri (The Ash Wednesday Supper), also published in 1584, Bruno defended the heliocentric theory of Copernicus, but it appears that he did not understand astronomy very well, for his theory is confused on several points.

In still another book published in 1584, De la Causa, Principio et Uno (On Cause, Prime Origin, and the One), Bruno seemed to anticipate Einstein’s theory of relativity when he wrote:

There is no absolute up or down, as Aristotle taught; no absolute position in space; but the position of a body is relative to that of other bodies. Everywhere there is incessant relative change in position throughout the universe, and the observer is always at the center of things.

Closeup of the statue of Bruno in the Campo de’ Fiori.

Some say that Bruno was executed because of his Copernicanism and his belief in the infinity of inhabited worlds, but it may have been for theological errors, such as denying the divinity of Christ. In fact, no one knows for certain the exact grounds on which he was declared a heretic because the volume or volumes of his Roman trial is missing from the Vatican archives. The only remaining record is a summary of the trial, rediscovered on November 15, 1940 and published in 1942. Some abstracts of Giordano Bruno’s works, his interrogations, some of the records of an earlier Venetian trial in 1592 against him, and some other documents copied from the original Roman trial converge in the summary, which was probably used by the Assessor of the Holy Office of that period. In this document, Bruno is quoted in one of the last interrogations by the judges of the Holy Office (maybe in April 1599) before his execution. He defended his theories as scientifically founded and by no means against the Holy Scriptures:

Firstly, I say that the theories on the movement of the earth and on the immobility of the firmament or sky are by me produced on a reasoned and sure basis, which doesn’t undermine the authority of the Holy Sciptures […]. With regard to the sun, I say that it doesn’t rise or set, nor do we see it rise or set, because, if the earth rotates on his axis, what do we mean by rising and setting[…].

Interestingly, while there is no definitive documentary evidence of Bruno’s sexual orientation, his homosexuality has long been assumed, principally on the basis of his association with figures such as Marlowe, the accusations of “immoral conduct,” and his authorship of Il Candelaio (1582). The latter is a satiric comedy for the stage whose very title, “The Candleholder,” is a homosexual slang word of the time, perhaps best rendered in contemporary English as “The Fudgepacker” or “The Butt-bandit.” The play presents three characters who are often seen as three of Bruno’s alter egos, or three facets of Bruno himself: Manfurio, a pedantic scholar who speaks tortured Latin and loses his glasses; Bonifacio, the “candleholder” homosexual who finally ends up in his wife’s bed; and Bartolomeo, the scientist and alchemist who tries to transmute base metals into gold but fails. The final words of Bruno’s introduction to Il Candelaio tell the reader, above all, Godete dumque, e si possete state sana, et amate chi v’ama (Therefore take pleasure in things, stay as healthy as you can, and love all those who love you).

Moreover, there is no evidence of any interest on Bruno’s part in opposite-sex sexual relations.

Both historian John Addington Symonds and aesthete Walter Pater discuss Bruno in detail. Each refers to Bruno’s homosexuality as a known, if covert, fact hidden in sly innuendo. Symonds devotes an entire chapter of his groundbreaking Renaissance in Italy to the philosopher, while Pater comments in an 1889 essay that for a man of the spirit, Bruno possessed “a nature so opulently endowed [it] can hardly have been lacking in purely physical ardours.” Symonds adds that his own development as a man was due to his readings of Walt Whitman, Goethe, and Giordano Bruno: they “stripped my soul of social prejudices [so that]… I have been able to fraternise in comradeship with men of all classes and several races.”

Italian gay activist and literary historian Giovanni dall’Orto cites Bruno in his 1988 survey, “Sodomy as Phoenix: Being Homosexual in the Italian Renaissance.” In a discussion of “unnatural” desires, he notes that part of the philosopher’s offense against the Church was to ascribe the Copernican world outlook to nature itself: whatever comes from within a man is by definition within nature. Hence, Bruno’s scientific outlook challenges the very notion of “natural law” and “crime against nature.” Again quoting Bruno from De la Causa, Principio et Uno (1584):

All things are in the Universe, and the Universe is in all things: we in it, and it in us; in this way everything concurs in a perfect unity.

On August 7, 1603, the Church placed all his works on the Index Librorum Prohibitorum (List of Forbidden Books). Four hundred years (!) after his execution, official expression of “profound sorrow” and acknowledgement of error at Bruno’s condemnation to death was made during the papacy of John Paul II.

Following the 1870 Capture of Rome by the newly created Kingdom of Italy and the end of the Church’s temporal power over the city, the erection of a monument to Bruno on the site of his execution became feasible. In 1885, an international committee, including Victor Hugo, Herbert Spencer, Ernest Renan, Ernst Haeckel, Henrik Ibsen, and Ferdinand Gregorovius, was formed for that purpose. The monument was sharply opposed by the clerical party, but was finally erected by the Rome Municipality and inaugurated in 1889.

A memorial to Giordano Bruno.

On March 2, 2008, a 6-meter-tall statue of an upside-down figure, evocative of flames, was unveiled in Berlin’s Potsdamer Platz station as a memorial to Giordano Bruno and as a new reminder of the value and cost of free thought [Science 319(5869): 1467 (14 March 2008)]. The sculpture is by Alexander Polzin. Ernst Salcher of the Giordano Bruno Foundation, which helped fund the project, said the sculpture is designed to “irritate” the viewer into reflecting on the role of human reason in making the world a better place.

Also, the SETI League (not to be confused with the SETI Institute) has established “an award honoring the memory of Giordano Bruno, the Italian monk burned at the stake in 1600 for postulating the multiplicity of inhabited worlds.” It was first suggested by sociologist Donald Tarter at a SETI dinner held at the American Association for the Advancement of Science meetings in Atlanta on 17 February 1995 (coincidentally the 395th anniversary of Bruno’s death). The Bruno Award is presented annually to a person or persons making significant technical contributions to the art, science, or practice of amateur SETI.

References:

February 15, 1564 (Julian calendar/old style: a Tuesday)

Galileo

On this date, the Florentine-Italian astronomer Galileo Galilei was born in Pisa, Italy. Galileo made a good discovery great. Upon hearing at age 40 that a Dutch optician had invented a glass that made distant objects appear larger, Galileo crafted his own telescope and turned it toward the sky. He quickly discovered that our Moon has craters, that Jupiter has its own moons, that the Sun has spots, and that Venus has phases like our Moon. Galileo, who lived to 1642, made many more discoveries. He claimed that his observations only made sense if all the planets revolved around the Sun, as championed by Aristarchus and Copernicus, and not around the Earth, as was commonly believed then. The powerful Roman Inquisition made Galileo publicly recant this conclusion, but today we know he was correct.

February 13, 1633 (a Sunday)

Galileo facing the Roman Inquisition.

On this date, Italian philosopher, astronomer and mathematician Galileo Galilei arrived in Rome to face charges of heresy for advocating Copernican theory, which holds that the Earth revolves around the Sun. Galileo officially faced the Roman Inquisition in April of that same year and agreed to plead guilty in exchange for a lighter sentence. Put under house arrest indefinitely by Pope Urban VIII, Galileo spent the rest of his days at his villa in Arcetri, near Florence, before dying on January 8, 1642.

Today, Galileo is recognized for making important contributions to the study of motion and astronomy. His work influenced later scientists such as the English mathematician and physicist Sir Isaac Newton, who developed the law of universal gravitation. In 1992, the Vatican formally acknowledged its mistake in condemning Galileo.

January 20, 1633

Galileo

On this date, Galileo, at age 68, left his home in Florence, Italy to face the Inquisition in Rome. After two weeks quarantine (because of the plague) just outside Rome, he arrived there on 13 February.

By 22 June 1633, he had buckled under the threats and interrogation by the Inquisition, and renounced his “belief” that the Earth revolved around the Sun.

Aside from his theoretical works, Galileo made several contributions to “technology” such as an improved telescope, a thermometer, a military compass and many many others. So great was his legacy that he was called by Einstein the “father of modern science.”

January 9, 1998 (a Friday)

Models

The story of how Dark Energy was discovered is a classic case of nature confounding expectations.

Ever since astronomers had accepted the idea of the Big Bang, they had been out hunting for its subsequent cosmic deceleration.

The idea was simple.

While the Big Bang blows space apart (it literally stretches all points of space-time away from each other), the gravitational pull of matter should, over time, slow down that initial burst of cosmic expansion. Two research groups, one at Berkeley and the other at Harvard, were racing to find the magnitude of deceleration in the universe. It was a critical project since the rate of cosmic braking is directly related to the total density of mass (and energy) in the universe.

Things didn’t go quite as planned. As data was gathered and analyzed, both the Harvard and Berkeley groups were stunned to find no evidence for deceleration. Instead, according to observations, the expansion of the universe was speeding up — it was accelerating. After exhaustively checking and rechecking their data, both groups bit the bullet and announced their results on this date (9 January 1998) at a meeting of the American Astronomical Society in New York City.

“All the indications from our observations of supernovas spanning a large range of distances are that we live in a universe that will expand forever,” said the leader of one team, Dr. Saul Perlmutter of Lawrence Berkeley National Laboratory in California. “Apparently there isn’t enough mass in the universe for its gravity to slow the expansion, which started with the Big Bang, to a halt.”

Dr. Peter Garnavich of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., a leader of the other team, said the low deceleration of the expansion rate means that the universe is much older, about 15 billion years old, than had been calculated by some astronomers, whose estimates had ranged as low as 8 billion years. If the universe was not expanding at a faster rate earlier, then it has taken longer for it to reach its present size.

In an independent study of the expansion rates of 14 distant radio galaxies, Dr. Ruth A. Daly, a Princeton University astronomer, said “our results are basically almost identical” to those of the Berkeley and Harvard-Smithsonian supernova observations. “We are 95 percent confident that the universe is going to expand forever,” Dr. Daly said.

Remarking on the close agreement of the different studies, Dr. Neta A. Bahcall, a Princeton astrophysicist, said this reinforced confidence that the conclusions are correct, or else everyone has overlooked some hidden flaw.

Where does Dark Energy appear in all this? As Newton showed 400 years earlier, accelerations need forces. And, as the physicists of the eighteenth and nineteenth centuries demonstrated, forces need energy. The discovery of cosmic acceleration meant that space was being forced apart and must, therefore, be pervaded by a new form of energy acting as “anti-gravity.” While Newtonian gravity only produces attractions, Einstein’s more complete description of gravity — as the shape of space-time — demonstrated that repulsion and gravity could go hand-in-hand.

The discovery of cosmic acceleration and Dark Energy upended cosmology almost overnight. In spite of the community’s incredulity, further studies, including studies of cosmic geometry, gave new support (multiple lines of evidence) for the reality of Dark Energy. Like it or not, this unanticipated form of anti-gravity was now a powerful actor on cosmology’s stage.

“Like it or not” is the key phrase. The history of science is stacked high with ideas and discoveries nobody was expecting, or even wanted. From the discovery of the muon (“who ordered that?” asked physicist I.I. Rabi) to climate change (the ultimate inconvenient truth), we don’t get to dictate to nature how it should behave. The greatest and strangest beauty of science is, in fact, this constant reminder of just how wrong we can be.

References:

January 2, 1960 (a Saturday)

John H. Reynolds

On this date, John Hamilton Reynolds, University of California/Berkeley physicist, announced that a meteorite which fell near Richardton, North Dakota in 1919 had yielded evidence that the Solar System is 4.95 billion years old. The age was determined by measuring the amount of the xenon isotope of mass 129 (or 129Xe), a rare radioactive gas, in the meteorite. The sample contained more of this rare gas than any other natural substance previously analyzed, Reynolds said.

Reynolds inferred that the 129Xe must have been produced from the radioactive decay of iodine-129 (or 129I), which was trapped in the meteor when the meteor formed.  Iodine-129 has a half-life of about 17 million years, meaning that half of any given quantity of it will turn into 129Xe in that time.  Then half of the remainder will turn into 129Xe in another 17 million years, and so on until the 129I is essentially all gone.  For most practical purposes, a radioactive material is no longer present after 10 or 20 of its half-lives. This is because 210 is about a thousand, and 220 is about a million.  So, after 20 half-lives, only one millionth of the original amount remains, too small to measure; twenty half-lives for 129I would be approximately 350 million years.

Four Possible Protoplanetary Disks in the Orion Nebula Revealed by the Hubble Telescope

Most elements were formed at the birth of the Universe, some 15 to 25 billion years ago, but 129I is produced in quantity in nature only by supernova explosions.  As the half-life of 129I is comparatively short in astronomical terms, the discovery of meteoritic 129Xe demonstrated that only a short time had passed between the supernova and the time the meteors had solidified and trapped the 129I. These two events (supernova and solidification of gas cloud) were inferred to have happened during the early history of the Solar System, as the 129I isotope was likely generated before the Solar System was formed, but not long before, and seeded the solar gas cloud isotopes with isotopes from a second source. A shock wave from such a supernova source may also have caused collapse of the solar gas cloud.

Since it was known that Earth was 4.6 billion years old, as measured with the uranium-lead technique by Clair Patterson, Harrison Brown, George Tilton, and Mark Inghram in 1953, it was only necessary to add 350 million years to estimate the age for formation of the solid bodies of the Solar System.

Letters in support of Reynolds’ discovery were glowing: “His work on meteorites…has revolutionized much of cosmological theory. His latest result is the most important single event in the whole field” (Willard Libby). “Reynolds has made an exceedingly important discovery, namely that there is a variation in the abundance of the isotopes of xenon in meteorites. The nature of this variation is two-fold: first, there is a special anomaly due to the decay of iodine-129 which shows that the meteorites were formed within a couple of hundred million years after the last important synthesis of the elements; and second, there is a general anomaly which indicates that nuclear processes of some kind were different for the meteorites than they were for the material of the Earth…I regard this as a very important discovery” (Harold Urey). “One can point to one particular accomplishment in his investigation of the xenon content of meteorites. The isotopic composition of xenon has led to most striking conclusions concerning the conditions under which our planetary system must have formed” (Edward Teller).

December 30, 1924 (a Tuesday)

Andromeda (seen here in ultraviolet).

Andromeda (seen here in ultraviolet).

On this date, Edwin Hubble announced his findings: “We are not alone”. Previously, the Milky Way Galaxy was considered the extent of the starry universe, but Hubble discovered that the spiral nebula Andromeda is actually a galaxy and that the Milky Way is just one of many galaxies in the universe. His discovery revolutionized the field of astronomy.

Hubble not only found a number of stars in Andromeda, he found Cepheid variable stars, which brighten and dim on a regular basis. Their brightness and periodicity had enabled a bright Harvard scholar, Henrietta Leavitt, twelve years earlier to figure out how to calculate their distances from Earth. Hubble used Leavitt’s formula to calculate that Andromeda was approximately 860,000 light years away. That’s more than eight times the distance to the farthest stars in the Milky Way. This conclusively proved that the nebulae are separate systems and that our galaxy is not the universe.

Hubble’s advances led to finding many more galaxies and the fact that they are moving away from ours – that the universe is still expanding.

Before Copernicus and Galileo, humans thought our world was the center of creation. Then (except for a few notable stragglers) we learned that the sun and planets did not revolve around the Earth, and we discovered that our sun — though the center of our solar system — was not the center of the universe or even an important star in our galaxy.

But we still grandiosely thought our own dear Milky Way contained all or most of the stars in existence. We were about to be knocked off our egotistical little pedestal once again.