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1609 - Galileo Galilei aimed his telescope at the Moon. While not being the first person to observe the Moon through a telescope (English mathematician Thomas Harriot had done it four months before but only saw a "strange spottednesse"), Galileo was the first to deduce the cause of the uneven waning as light occlusion from lunar mountains and craters. In his study, he also made topographical charts, estimating the heights of the mountains.
1610 - Galileo Galilei becomes the first to observe Saturn's rings with his 20-power telescope. He thought the rings were "handles" or large moons on either side of the planet. He said "I have observed the highest planet [Saturn] to be tripled-bodied. This is to say that to my very great amazement Saturn was seen to me to be not a single star, but three together, which almost touch each other".
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 10 January, 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 moons. He discovered the fourth on 13 January. Galileo named the group of four the Medicean stars, in honour of his future patron, Cosimo II de' Medici, Grand Duke of Tuscany, and Cosimo's three brothers. Later astronomers, however, renamed them Galilean satellites in honour of their discoverer. These satellites were independently discovered by Simon Marius on 8 January 1610 and are now called Io, Europa, Ganymede, and Callisto, the names given by Marius in his Mundus Iovialis published in 1614.
1610 - Galileo observed that Venus exhibits a full set of phases similar to that of the Moon. The heliocentric model of the Solar System developed by Nicolaus Copernicus predicted that all phases would be visible since the orbit of Venus around the Sun would cause its illuminated hemisphere to face the Earth when it was on the opposite side of the Sun and to face away from the Earth when it was on the Earth-side of the Sun.
In Ptolemy's geocentric model, it was impossible for any of the planets' orbits to intersect the spherical shell carrying the Sun. Traditionally, the orbit of Venus was placed entirely on the near side of the Sun, where it could exhibit only crescent and new phases. It was also possible to place it entirely on the far side of the Sun, where it could exhibit only gibbous and full phases.
After Galileo's telescopic observations of the crescent, gibbous and full phases of Venus, the Ptolemaic model became untenable.
In the early 17th century, as a result of his discovery, the great majority of astronomers converted to one of the various geo-heliocentric planetary models, such as the Tychonic, Capellan and Extended Capellan models, each either with or without a daily rotating Earth. These all explained the phases of Venus without the 'refutation' of full heliocentrism's prediction of stellar parallax. Galileo's discovery of the phases of Venus was thus his most empirically practically influential contribution to the two-stage transition from full geocentrism to full heliocentrism via geo-heliocentrism.
Source: https://en.wikipedia.org/wiki/Galileo_Galilei
Galileo's telescope.
This is the reality of what can be ssen through a telescope with the specifications of the telescope held in the Galileo Museum and allegedly used by Galileo.
The image is tiny, blurred and without a modern tripod, the telescope is easily moved and the image lost.
Source: https://www.youtube.com/watch?v=7W-i6nn7esU&t=14s
This is the reality of what can be seen of the Moon. It is impossible to view the entire Moon; only a part of it.
The image is tiny, blurred and without a modern tripod, the telescope is easily moved and the image lost.
1655 - Huygens discovered the first of Saturn's moons, Titan, and observed and sketched the Orion Nebula using a refracting telescope with a 43x magnification of his own design. Huygens succeeded in subdividing the nebula into different stars (the brighter interior now bears the name of the Huygenian region in his honour), and discovered several interstellar nebulae and some double stars. He was also the first to propose that the appearance of Saturn, which have baffled astronomers, was due to "a thin, flat ring, nowhere touching, and inclined to the ecliptic”.
More than three years later, in 1659, Huygens published his theory and findings in Systema Saturnium. It is considered the most important work on telescopic astronomy since Galileo's Sidereus Nuncius fifty years earlier. Much more than a report on Saturn, Huygens provided measurements for the relative distances of the planets from the Sun, introduced the concept of the micrometer, and showed a method to measure angular diameters of planets, which finally allowed the telescope to be used as an instrument to measure (rather than just sighting) astronomical objects. He was also the first to question the authority of Galileo in telescopic matters, a sentiment that was to be common in the years following its publication.
In the same year, Huygens was able to observe Syrtis Major, a volcanic plain on Mars. He used repeated observations of the movement of this feature over the course of a number of days to estimate the length of day on Mars, which he did quite accurately to 24 1/2 hours. This figure is only a few minutes off of the actual length of the Martian day of 24 hours, 37 minutes.
Source: https://en.wikipedia.org/wiki/Christiaan_Huygens
All done with a totally inadequate telescope design.
1671 - Cassini observed and published surface markings on Mars (earlier seen by Christiaan Huygens but not published), determined the rotation periods of Mars and Jupiter, and discovered four satellites of Saturn: Iapetus and Rhea in 1671 and 1672, and Tethys and Dione (1684). Cassini was the first to observe these four moons, which he called Sidera Lodoicea (the stars of Louis), including Iapetus, whose anomalous variations in brightness he correctly ascribed as being due to the presence of dark material on one hemisphere (now called Cassini Regio in his honour). In addition he discovered the Cassini Division in the rings of Saturn (1675). He saw the Great Red Spot on Jupiter. Around 1690, Cassini was the first to observe differential rotation within Jupiter's atmosphere.
Source: https://en.wikipedia.org/wiki/Giovanni_Domenico_Cassini
All done with a totally inadequate telescope design.
1676 - Danish astronomer Ole Rømer allegedly made the first measurement of the speed of light.
The key phenomenon that Rømer observed was that the time elapsed between eclipses was not constant. Rather, it varied slightly at different times of year. Since he was fairly confident that the orbital period of Io was not actually changing, he deduced that this was an observational effect. The orbital paths of Earth and Jupiter being available to him, he noticed that periods in which Earth and Jupiter were moving away from each other always corresponded to a longer interval between eclipses. Conversely, the times when Earth and Jupiter were moving closer together were always accompanied by a decrease in the eclipse interval. This, Rømer reasoned, could be satisfactorily explained if light possessed a finite speed, which he went on to calculate.
By timing the eclipses of the Jovian moon Io, Rømer estimated that light would take about 22 minutes to travel a distance equal to the diameter of Earth's orbit around the Sun. Using modern orbits, this would imply a speed of light of 226,663 kilometres per second, 24.4% lower than the true value of 299,792 km/s. In his calculations Rømer used the idea and observations that the apparent time between eclipses would be greater when the Earth relatively moves away from Jupiter and lesser while moving closer.
Source: https://en.wikipedia.org/wiki/Ole_R%C3%B8mer
All done with a totally inadequate telescope design.
The Copenhagen Fire of 1728 was the largest fire in the history of Copenhagen, Denmark. It began on the evening of 20 October 1728 and continued to burn until the morning of 23 October. It destroyed approximately 28% of the city (measured by counting the number of destroyed lots from the cadastre) and left 20% of the population homeless. The reconstruction lasted until 1737. No less than 47% of the section of the city, which dates back to the Middle Ages, was completely lost, and along with the Copenhagen Fire of 1795, it is the main reason that few traces of medieval Copenhagen can be found in the modern city.
Although the number of dead and wounded was relatively low compared to the extent of the fire, the cultural losses were huge. In addition to several private book collections, 35,000 texts including a large number of unique works were lost with the University of Copenhagen library, and at the observatory on top of Rundetårn, instruments and records made by Tycho Brahe and Ole Rømer were destroyed.
Instruments and records made by Tycho Brahe and Ole Rømer were destroyed.
How very convenient!
The University of Copenhagen library was without a doubt the greatest and the most frequently mentioned of such. 35,000 texts and a large archive of historical documents disappeared in the flames. Original works from the historians Hans Svaning, Anders Sørensen Vedel, Niels Krag, and Arild Huitfeldt and the scientists Ole Worm, Ole Rømer, Tycho Brahe and the brothers Hans and Caspar Bartholin were lost. Atlas Danicus by Peder Hansen Resen and the archive of the Diocese of Zealand went up in flames as well. The archive of the diocese had been moved to the university library the very same day the fire started.
Source: https://en.wikipedia.org/wiki/Copenhagen_Fire_of_1728#Thursday
Fires are a recurring event when researching 'history' and they do allow the past to be wiped out and lies made up.
Equipment used at the Sobral, Brazil site. The metal telescope is on the left and the wooden telescope is on the right. The circular reflecting mirrors (coelostats) are in front of the telescopes.
Albert Einstein published his theory of Special Relativity in 1905 and his General Theory in 1915. One of the predictions of the General theory, is that the Sun will displace the images of nearby stars. The light rays will be bent by the Sun's gravitaional field. He predicted a displacement of 1.75 arcseconds (1" .75).
In 1917, in response to the publication of Einstein’s theory, Frank Dyson, the Astronomer Royal and director of the Royal Observatory Greenwich, published a paper reporting his failure to measure a significant displacement for the few stars visible on eclipse plates taken in 1905. He predicted that the total eclipse in 1919 would provide a much better chance of success, as the Sun would be situated in the richer star field of the Hyades.
A British expedition was organised under the direction of Dyson. It was decided that two groups of two observers would be sent. One group, consisting of staff from the Royal Observatory, Greenwich, went to Sobral in Brazil. The second group, from the Cambridge Observatory, went to the Island of Principe, a small volcanic island 220 km off the West African coast. The Greenwich group consisted of Andrew Crommelin and his more junior colleague Charles Davidson. The Cambridge group consisted of the Observatory’s Director, Arthur Eddington, and Edwin Cottingham who looked after the Observatory’s clocks. The expeditions were supported and partially funded by the joint standing eclipse committee of the Royal Society and Royal Astronomical Society.
There were many problems with the glass photographic plates, blurred images due to the heat of the sun warping the mirror and cloud covering the sun.
These are quotes from the official report:
“May 30, 3 a.m., four of the astrographic plates were developed and when dry examined. It was found that there had been a serious change of focus, so that, while the stars were shown, the definition was spoilt. This change in focus can only be attributed to the unequal expansion of the mirror through the sun’s heat. The readings of the focussing scale were checked the next day, but were found unaltered at 11.0 mm. It seems doubtful whether much can be got from these plates.”
“In summarising the results of the two expeditions, the greatest weight must be attached to those obtained with the 4-inch lens at Sobral.”
Here, Dyson, Eddington and Davidson are stating in the report that the photographs taken with the borrowed wooden telescope used by Crommelin were superior to those taken with a metal astrographic telescope.
The reults obtained by Andrew Crommelin using the astrographic lens and metal tubes, was 0.93 arcseconds (0" . 93) displacement.
It is clear from reading the report that in order to get the desired 1.75 arcseconds (1” . 75) displacement of observed stars, and confirm the theory put forth by Einstein, Eddington cherry-picked data and ignored the 0” . 93 results obtained by Crommelin.
Quote:
“There remain the Sobral astrographic plates which gave the deflection 0” . 93 discordant by an amount much beyond the limits of accidental error. For the reasons already described at length not much weight is attached to this determination.”
In other words, these results will be totally ignored!
Source: http://www.royalobservatorygreenwich.org/articles.php?article=1283
Source: https://www.nature.com/articles/d41586-019-01172-z
A copy of one of the original photographic glass plates showing the eclipse. None of the original plates from either expedition have survived!
Eddington’s plates were lost after he died in 1944 — his sister might have thrown them away when she was forced to move out of the Cambridge home they had shared.
Crommelin’s plates seem to have disappeared in the course of successive reorganizations at the Royal Observatory.
Again, how very convenient that vital evidence has been lost!
How do we know that the originals and subsequent copies were not subject to photo manipulation?
The ghost of Abraham Lincoln stands over his widow, Mary Todd Lincoln.
William Mumler’s famous image and an example of photographic manipulation using equipment and processes available in the 1800's.
William H. Mumler (1832–1884) was an American spirit photographer who worked in New York and Boston. His first spirit photograph was apparently an accident—a self-portrait which, when developed, also revealed the "spirit" of his deceased cousin. Mumler then left his job as an engraver to pursue spirit photography full-time, taking advantage of the large number of people who had lost relatives in the American Civil War. His two most famous images are the photograph of Mary Todd Lincoln with the ghost of her husband Abraham Lincoln and the portrait of Master Herrod, a medium, with three spirit guides.
Mumler was eventually taken to court and tried for fraud and larceny. Noted showman P. T. Barnum testified against him. He was later acquitted by a judge, and his photography career continued. Today, Mumler's photographs are recognized as fakes but they circulated widely during the last quarter of the 19th century and were marketed as objects of belief and visual curiosities both within and beyond the spiritualist movement. He later discovered a process, called the "Mumler Process", by which photo-electrotype plates could be produced and printed more easily.
https://en.wikipedia.org/wiki/William_H._Mumler
The Michelson–Morley experiment was an attempt to detect the existence of the luminiferous aether, a supposed medium permeating space that was thought to be the carrier of light waves. The experiment was performed between April and July 1887 by American physicists Albert A. Michelson and Edward W. Morley at what is now Case Western Reserve University in Cleveland, Ohio, and published in November of the same year.
The experiment compared the speed of light in perpendicular directions (at right angles to each other) in an attempt to detect the relative motion of matter through the stationary luminiferous aether ("aether wind"). The result was negative, in that Michelson and Morley found no significant difference between the speed of light in the direction of movement through the presumed aether, and the speed at right angles.
The expected speed was 30 kilometers per second as this is the alleged speed of Earth around the Sun. The actual speed measured was only 1 - 10 kilometers per second. It was described as a null result.
The Earth was apparently stationary.
Source: https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment
The apparatus is solidly built, is mounted on a stone slab that floats in an annular trough of mercury.
Lorentz was one of few scientists who supported Einstein's search for general relativity from the beginning – he wrote several research papers and discussed with Einstein personally and by letter.
He wrote in 1919:
“The total eclipse of the sun of May 29, resulted in a striking confirmation of the new theory of the universal attractive power of gravitation developed by Albert Einstein, and thus reinforced the conviction that the defining of this theory is one of the most important steps ever taken in the domain of natural science.”
George Francis FitzGerald was an Irish academic and physicist who served as Erasmus Smith's Professor of Natural and Experimental Philosophy at Trinity College Dublin from 1881 to 1901. He is known for his work in electromagnetic theory and for the Lorentz–FitzGerald contraction, which became an integral part of Albert Einstein's special theory of relativity.
In a letter to the editor of ‘Science’ in 1889, he proposed that the best way to explain the null result of the Michelson - Morley experiment was to assume that the length of an object was not constant. Objects moving through the aether with a velocity v were contracted by a factor of v2/c2 where c is the speed of light.
In order to falsify the results of the Michelson and Morley experiment and rescue Einstein's theories, the concept of 'length contraction' was invoked.
This involved the 'Lorentz -Fitzgerald contraction theory (length contraction).
This meant that the part of the interferometer which faced West was subject to length contraction as it woud be travelling against the 'ether wind'. The arm which faced North would not suffer any length contraction. This would explain the slight differences in the recorded speed of light beam travelling North and the light beam travelling West.
A mile long pipe made from corrugate, galvanised steel was erected on the grounds of the Irvine Ranch, Orange County in America.
In 1931, Michelson set up an experiment to determine the speed of light and prove the theories of Albert Einstein regarding the fixed speed of light and of Relativity.
Since 1929, Michelson and Mount Wilson staff were actively looking to “borrow” some sort of existing pipeline for their experiments. They approached a number of gas companies, as well as water districts, seeing if there were any pipelines available for their use. Not surprisingly, the answer they received was “NO”!
While looking for locations in Orange County, Mount Wilson staff happened to speak at length with the Engineer for the Irvine Ranch, C.R. Browning. He told them that while they didn’t have a pipeline Michelson could use, his boss, James Irvine, might be interested in letting Michelson temporarily install a surface pipeline on Irvine Ranch. Since Michelson had at his disposal $67,500 (Rockefeller funding of $30,000, a Carnegie Grant of $27,500 and University of Chicago money of $10,000), at that point it appeared the only way he would have his pipeline was if he built it himself. So on July 20, 1929, Adams wrote James Irvine formally asking permission to use part of the Irvine Ranch for the next round of Michelson’s speed of light experiments. On July 24th, Irvine replied in the affirmative, and work began.
https://www.otherhand.org/home-page/physics/historical-speed-of-light-measurements-in-southern-california/irvine-ranch-measurements-1929-1933/
The main reflecting mirrors were 22″ diameter flat mirrors at each end of the evacuated tube. Between these two mirrors was reflected a collimated beam from an arc lamp. This was very similar to what Michelson had done with his early tests, but there was a new twist here. In order to get the maximum length possible of the light path, the light made multiple trips up and down the length of the pipe, for a total of either 8 or 10 miles. There was the usual rotating, faceted mirror, but this time it had 32 facets and was spun by compressed air at 1,000 revolutions per second (60,000 RPM!).
During the operational life of the apparatus, from February 1931 until February 1933, a total of 233 measurements were made, roughly divided into fourths. Michelson died on May 9, 1931 when the first 36 measurements had been completed. The balance of the measurements were taken by Francis Pease and Fred Pearson.
The results were not as satisfactory as the San Antonio experiments. Much of it was due to the vacuum, or lack thereof. Michelson originally thought a vacuum of 2″ (50 mm of Mercury) would be adequate for good seeing. However it was found that to get sharp images in the tube, vacuum levels had to be brought down to 1 to 2 mm of Mercury. Given the many pipe joints, method of sealing and power of the pumps, this was almost impossible to achieve.
During the operational life of the apparatus, from February 1931 until February 1933, a total of 233 measurements were made, roughly divided into fourths. Michelson died on May 9, 1931 when the first 36 measurements had been completed. The balance of the measurements were taken by Francis Pease and Fred Pearson.
The results were not as satisfactory as the San Antonio experiments. Much of it was due to the vacuum, or lack thereof. Michelson originally thought a vacuum of 2″ (50 mm of Mercury) would be adequate for good seeing. However it was found that to get sharp images in the tube, vacuum levels had to be brought down to 1 to 2 mm of Mercury. Given the many pipe joints, method of sealing and power of the pumps, this was almost impossible to achieve.
All of the sections of pipe were riveted. Such joints are not airtight and will not sustain a vacuum.
The sections are all riveted together and this method is not airtight.
The cast metal sections are stich welded together and this method is not airtight and will not support a vacuum. To the left of Michelson is the small opening used to send and recieve the light beam from an arc light. How do we know that this opening was actually sealed duringthe tests? It would have to have thick glass fitted and effectively sealed.
The stitch welds have been highlighted. How is the round opening sealed off? There doesn't appear to be any means of fixing thick glass to it.
The speed of light in vacuum, commonly denoted c, is a universal physical constant that is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour).
It is exact because, by a 1983 international agreement, a metre is defined as the length of the path travelled by light in vacuum during a time interval of 1⁄299792458 second. This particular value was chosen to provide a more accurate definition of the metre that still agreed as much as possible with the definition used before.
According to the special theory of relativity, c is the upper limit for the speed at which conventional matter or energy (and thus any signal carrying information) can travel through space.
In theoretical engineering and physics, a vacuum refers to a perfect vacuum devoid of all matter.
In engineering and applied physics, a vacuum refers to any space in which the pressure is considerably lower than atmospheric pressure.
The absolute speed of light in a perfect vacuum is a theory not a fact.
All tests and measurements are carried out in a situation where the vacuum is defined as a pressure lower than atmospheric.
All measurements are approximations and are therefore one chosen variable from a set of measured variables; usually this is the average value.
The fixed speed of light in a perfect vacuum is a theory not a fact and has never been measured.
299,792,459 meters per second is the average variable from a range of data that has been agreed upon by a consensus to be put forth as an absolute.
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