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A lot of asteroids are orbiting in the Solar System. Yet they are missing from most medals, which depicts the solar system's planets. There are fortunately rare exceptions.

leverrier reverse

Alphee Dubois made a bronze commemorative medal in 1884 in honor of a discovery. The medal was made by the Paris mint. The title BRONZE and the cornucopia struck into the edge refer to this. Its diameter is 68 mm and weighs 166 grams. It is not considered to be a rare thing when you issue a commemorative medal in honor of a discovery. It is much rarer when the same coin anticipates a discovery. What happens if the discovery of which we are sure does not exist? Can we certainly state in the possession of our trusted theories the existence of something we have not found yet? As we will see the answer is no. But let us go in turn. The discovery of Neptune led to the chain of events, which was very adventurous and has become a shining example of the French-English rivalry.

The discoverer of the planet Neptune was Urbain Le Verrier (1811-1877) a French mathematician who - in contrast to previous discoveries, which astronomers made with telescopes - he used paper and pencil at his desk to find the eighth planet of the solar system. The fact that there should be an eighth planet is already became clear in 1841 to John Couch Adams (1819-1892), an English mathematician and astronomer, who - correctly - attributed the deviation of orbit of the planet Uranus from the calculated one to an unknown planet. He sent his calculations to Sir George Airy the English Astronomer Royal, who showed no particular interest and returned the calculations for "further clarification". Adams made the mistake not to pursue the matter, leaving the question of the new planet to lay off.

leverrier obverse

In 1845-46 Le Verrier, entirely independently of Adams came to a similar conclusion regarding the unknown planet. He calculated its position in the sky where it should be. The results were sent to many of the astronomers of the world, but he also had to experience the lack of interest of his colleagues. Finally, in June Airy - seeing that Adams and Le Verrier reported similar coordinates - convinced the head of the Cambridge observatory, James Challis to launch the search. But Challis instead of aiming the telescope at the given coordinates had led a systematic search in August and September at the given part of the sky, without any result.

Meanwhile, Le Verrier wrote a letter to Johann Gottfried Galle the Director of the Berlin Observatory, urging to start the search. Heinrich d'Arrest - who then was a student in the observatory - has suggested to Galle to compare the recent drawings from the area, with what they see in the telescope. After all, if the planet exists, in the meantime it also had to move relative to the stars. On the same evening, September 23, 1846, when Le Verrier's letter was received, they found the Neptune, less than 1 degree from the point Le Verrier calculated. It later became clear that Challis saw the planet twice in August, but had overlooked it. Thus, the final glory went to the French and Germans.

At first glance there is nothing special on the medal. On the obverse Le Verrier's left-facing bust is visible. Legend around is: "U.J.J.LE-VERRIER DE L'ACADEMIE DES SCIENCES. 1811-1877". Over the shoulder of Le Verrier, the year 1884 and the engraver's name in shown. On the reverse the Solar System is drawn by the artist, mostly by allegorical persons. In the middle the Sun on a Quadriga is visible. Around him are the planets in order of their distances from the Sun. After Mercury, Venus, Earth and Mars - at the top of the medal - the asteroids are visible (PETITES PLANETES).

leverrier reverse

The fact that the asteroids were displayed on the coin indicates that an astronomer helped the design of the coin. The number of known asteroids now is more than a hundred thousand. The first was discovered in 1801, and in 1884 when this medal was made their number was already taken over 100. They are not a negligible part of the Solar System, yet most modern coins are missing them.

Continuing the line of distance from the Sun, the picture of Jupiter, Saturn, Uranus and the newly discovered Neptune follows. Do not look for Pluto. It had to wait until 1930 to be discovered. The found of Pluto - as in the case of Neptune - is resulted from the fact that the planet's gravitational field distorted the orbits of other planets, leaving a trail of its existence and inspired the search. But it is not a really big problem that it is missing from the medal, because since 2006 Pluto is no longer considered a planet, but a member and the namesake of another group of celestial bodies - the plutoids. It could be on the medal only as the asteroids, as a group of celestial bodies. However, there was not any indication in 1884 for this.