The French mathematician Urbain Le Verrier , co-predictor with J.C. Adams of the position of Neptune before it was seen, in a lecture at 2 Jan 1860 announced that the problem of observed deviations of the motion of Mercury could be solved golf cruise vacation and spa cruise vacation package by assuming an intra-Mercurial planet, or possibly a second asteroid belt inside Mercury's orbit. The only possible way to observe this intra-Mercurial planet or asteroids was if/when golf cruise vacation and spa cruise vacation package they transited the Sun, or during total solar eclipses. Prof. Wolf at the Zurich sunspot data center, found a number of suspicious "dots" on the Sun , and another astronomer found some more. A total of two dozen spots seemed to fit the pattern of two intra-Mercurial golf cruise vacation and spa cruise vacation package orbits, one with a period of 26 days and the other of 38 days.
In 1859, Le Verrier received a letter from the amateur astronomer Lescarbault, who reported having seen a round black spot on the Sun on March 26 1859, looking like a planet transiting the Sun. He had seen the spot one hour and a quarter, when it moved a quarter of the solar diameter. Lescarbault golf cruise vacation and spa cruise vacation package estimated the orbital inclination to between 5.3 and 7.3 degrees, its longitude of node about 183 deg, its eccentricity golf cruise vacation and spa cruise vacation package "enormous", and its transit golf cruise vacation and spa cruise vacation package time across the solar disk 4 hours 30 minutes. Le Verrier investigated this observation, and computed an orbit from it: period 19 days 7 hours, mean distance from Sun 0.1427 a.u., inclination 12# 10', ascending node at 12# 59' The diameter was considerably smaller than Mercury's and its mass was estimated at 1/17 of Mercury's mass. This was too small to account for the deviations of Mercury's orbit, but perhaps this was the largest member of that intra-Mercurial asteroid belt? Le Verrier fell in love with the planet, and named it Vulcan .
In 1860 there was a total eclipse of the Sun. Le Verrier golf cruise vacation and spa cruise vacation package mobilized all French and some other astronomers to find Vulcan - nobody did. Wolf's suspicious 'sunspots' golf cruise vacation and spa cruise vacation package now revived Le Verrier's interest, and just before Le Verrier's golf cruise vacation and spa cruise vacation package death in 1877 some more 'evidence' found its way into print. On April 4 1875, a German astronomer, H. Weber, golf cruise vacation and spa cruise vacation package saw a round spot on the Sun. Le Verrier's orbit indicated a possible transit at April 3 that year, and Wolf noticed that his 38-day orbit also could have performed a transit at about that time. That 'round dot' was also photographed at Greenwich and in Madrid.
There was one more flurry after the total solar eclipse at July 29 1878, where two observers claimed to have seen in the vicinity of the Sun small illuminated disks which could only be small planets inside Mercury's orbit: J.C Watson (professor of astronomy at the Univ. of Michigan) believed he'd found TWO intra-Mercurial planets! Lewis Swift (co-discoverer of Comet Swift-Tuttle, which returned 1992), also saw a 'star' he believed to be Vulcan -- but at a different position than either of Watson's two 'intra-Mercurials'. In addition, neither Watson's nor Swift's Vulcans could be reconciled with Le Verrier's golf cruise vacation and spa cruise vacation package or Lescarbault's Vulcan.
After this, nobody ever saw Vulcan again, in spite of several searches at different total solar eclipses. And in 1916, Albert Einstein published his General Theory of Relativity, golf cruise vacation and spa cruise vacation package which explained the deviations in the motions of Mercury without the need to invoke an unknown intra-Mercurial planet. In May 1929 Erwin Freundlich, Potsdam, photographed the total solar eclipse in Sumatra, and later carefully examined the plates which showed a profusion of star images. Comparison plates were taken six months later. No unknown object brighter than 9th magnitude was found near the Sun.
But what did these people really see? Lescarbault had no reason to tell a fairy tale, and even Le Verrier believed him. It is possible that Lescarbault happened to see a small asteroid passing very close to the Earth , just inside Earth's golf cruise vacation and spa cruise vacation package orbit. Such asteroids were unknown at that time, so Lescarbault's only idea was that he saw an intra-Mercurial planet. Swift and Watson could, during the hurry to obtain observations during totality, have misidentified some stars, believing they had seen Vulcan.
"Vulcan" was briefly revived around 1970-1971, when a few researchers thought they had detected several faint objects close to the Sun during a total solar eclipse. These objects might have been faint comets , and later comets have been observed that later did pass close enough to the Sun to collide with it.
Two days before the 29 March 1974 Mariner 10 flyby past Mercury , one instrument began registering bright emissions in the extreme UV that had "no right to be there". The next day it was gone. Three days later it reappeared, and the "object" appeared to detach itself from Mercury. The astronomers first thought they had seen a star. But they had seen it in two quite different directions, and every astronomer knew that these extreme UV wavelengths couldn't penetrate very far through the interstellar medium, suggesting that the object must be close. Did Mercury have a moon?
After a hectic golf cruise vacation and spa cruise vacation package Friday, when the "object" had been computed to move at 4 km/s, a speed consistent with that of a moon, JPL managers were called in. They turned the then-dying golf cruise vacation and spa cruise vacation package spacecraft over full time to the UV team, and everyone started worrying golf cruise vacation and spa cruise vacation package about a press conference scheduled for later that Saturday. Should the suspected moon be announced? But the press already knew. Some papers -- the bigger, more respectable ones -- played it straight; many others ran excited stories about Mercury's new moon.
And the "moon" itself? It headed straight on out from Mercury, and was eventually identified as a hot star, 31 Crateris. What the original emissions came from, the ones spotted on the approach to the planet, remains a mystery. So ends the story of Mercury's moon but at the same time a new chapter in astronomy began: extreme UV turned out not to be so completely golf cruise vacation and spa cruise vacation package absorbed by the interstellar medium as formerly believed. Already the Gum nebula has turned out to be a quite strong emitter in the extreme UV, and spreads across 140 degrees of the night sky at 540 angstroms. Astronomers had discovered a new window through which to observe the heavens.
In 1672, Giovanni Domenico Cassini , one of the prominent astronomers of the time, noticed a small companion close to Venus . Did Venus have a satellite? Cassini decided not to announce his observation, but 14 years later, golf cruise vacation and spa cruise vacation package in 1686, he saw the object again, and then entered it in his journal. The object was estimated to have about 1/4 the diameter of Venus, and it showed the same phase as Venus. Later, the object was seen by other astronomers as well: by James Short in 1740, Andreas Mayer in 1759, J. L. Lagrange in 1761 (Lagrange announced that the orbital plane of the satellite was perpendicular to the ecliptic). During 1761 the object was seen a total of 18 times by five observers. The observations of Scheuten on June 6 1761 was especially interesting: he saw Venus in transit across the Sun's disk, accompanied by a smaller dark spot on one side, which followed golf cruise vacation and spa cruise vacation package Venus in its transit. golf cruise vacation and spa cruise vacation package However, Samuel Dunn at Chelsea, England, who also watched that transit, did not see that additional spot. In 1764 there were 8 observations by two observers. Other observers tried to see the satellite golf cruise vacation and spa cruise vacation package but failed to find it.
Now the astronomical world was faced with a controversy: several observers had reported seeing the satellite while several others had failed to find it in spite of determined efforts. In 1766, the director of the Vienna observatory, Father Hell (!), published a treatise where he declared that all observations of the satellite were optical illusions -- the image of Venus is so bright that it is reflected in the eye, back into the telescope, creating a secondary image at a smaller scale. Others published treatises declaring that the observations were real. J. H. Lambert of Germany published orbital elements of the satellite in Berliner Astronomischer Jahrbuch 1777: mean distance 66.5 Venus radii, orbital period 11 days 3 hours, inclination to ecliptic 64 degrees. It was hoped that the satellite could be seen during the transit of Venus in front of the Sun June 1 1777 (it is self evident that Lambert made a mistake in calculating these orbital elements: at 66.5 Venus radii, the distance from Venus is about the same as our Moon 's distance from the Earth . This fits very badly with the orbital period of 11 days or only somewhat more than 1/3 of the orbital period of our Moon. The mass of Venus is a little smaller than the mass of the Earth).
In 1768 there was one more observation of the satellite, by Christian Horrebow in Copenhagen. There were also three searches, one made by one of the greatest astronomers of all time, William Herschel -- all three of them failed to find any satellite. Quite late in the game, F. Schorr from Germany tried to make a case for the satellite golf cruise vacation and spa cruise vacation package in a book published in 1875.
In 1884, M. Hozeau, former director of the Royal Observatory of Brussels, suggested a different hypothesis. By analysing available observations Hozeau concluded that the Venus moon appeared close to Venus approximately every 2.96 years or 1080 days. Hozeau suggested that it wasn't a moon of Venus, but a planet of its own, orbiting the sun once every 283 days and thus being in conjunction with Venus once every 1080 days. Hozeau also named it Neith, golf cruise vacation and spa cruise vacation package after the mysterious golf cruise vacation and spa cruise vacation package goddess of Sais, whose veil no mortal raised.
In 1887, three years after the "moon of Venus" had been revived by Hozeau, the Belgian Academy of Sciences published a long paper where each and every reported observation was investigated in detail. Several observations of the satellite were really stars seen in the vicinity of Venus. Roedkier's observations "checked out" especially well -- he had been fooled, in succession, by Chi Orionis, M Tauri, 71 Orionis, and Nu Geminorum! James Short had really seen a star somewhat fainter than 8th magnitude. All observations golf cruise vacation and spa cruise vacation package by Le Verrier and Montaigne could be similarly explained. Lambert's orbital calculations were demolis
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