It was the brightest and most observed comet of the 20th century. It was visible to the naked eye for a record 18 months, twice as long as the previous record holder, the Great Comet of 1811.
The discovery of Comet Hale-Bopp happened on 23 July 1995, when it was still in a great distance from the Sun, raising expectations that the comet would brighten considerably by the time it passed close to Earth. Two independent American observers discovered it, Alan Hale and Thomas Bopp. In spite of that more German medals were struck than American.
The only medal from US was made of 925 fine sterling silver, with a standard crown diameter, 38.6 mm, 23.5 grams weight and a high gloss proof finish. On the obverse a large comet over the countryside landscape is observed by two men, father and son. On the reverse the orbits of the comet and the solar system's inner planets are located. It can be seen that the comet's orbit is almost perpendicular to the plane of ecliptic. As legend the names of the planets, the fineness of the coin's material, and the mintmark is visible. The medal was struck by the Franklin Mint. Legend around: "HALE-BOPP COMET", and "The biggest & brightest of the 20th century". The date was left out from the coin.
The other medals were issued in German-speaking countries. Also labels Hale-Bopp as the comet of the century a nickel medal with a diameter 35.3mm, on obverse with the comet hanging over a small-town landscape. On the sky are stars, arranged into constellations. Recognizable are Cassiopeia, the Swan, the Pegasus and Andromeda. Below the comet is named "HALE-BOPP." On the reverse is a - yet unknown - observatory. The issuer of the coin has not been identified yet. Legend around is: "WIR HABEN DEN » JAHRHUNDERT - KOMETEN « GESEHEN", that is we have seen the comet of the century, and 1997.
The next pair of medals have the same design, only they have of different sizes. The larger 999-silver medal is 50mm in diameter and weighs 50 grams. On the obverse the nucleus of the comet is gilt. The constellations Cassiopeia, Andromeda and Perseus are identified by name. On the bottom the geographical network map of the Earth was placed. Legend above: "HALE-BOPP DER JAHRTAUSEND-KOMET", that is this coin states Hale-Bopp as the comet of the millennium. Below: "ERDNÄCHSTE POSITION 196.6 MIL. KM - 23.3.1997", gives the perigee distance and time. On the reverse is the so-called "Flammarion engraving" by an unknown artist, actually it appeared for the first time in Flammarion's book published in 1888. Legend around: "EIN MENSCHHEITSTRAUM DIE ENTDECKUNG DES UNIVERSUMS IM MITTELALTER", that is, a man's dream to explore the universe in the Middle Ages.
The smaller coin is only 35mm in diameter and weighs 20 grams. The picture of the medal is the same as the larger piece except that the comet's core is not gilt.
On the obverse of the the next German medal also the Globe's geographical network is visible, but some trees appear in the distance. The path of the comet on the sky among the stars is marked by a thick arrows. The constellations Swan (Schwan), Cassiopeia and Pegasus are identified. On the reverse side the Globe, the Sun and the comet can be seen, while the legend also calls Hale-Bopp as the comet of the millennium. The medal is made of 999 silver, in 40mm diameter and 30 grams weight.
On the obverse of the following silver medal people traveling away from the light pollution of the city observe the comet flying among the stars. The legend:"KOMET HALE -BOPP 1997" and "EROBERUNG DES WELTRAUMS", that is the conquest of outer space text can be read. On the reverse the map of Germany and German provinces with their coat of arms are pictured. Below 999 indicates the fineness of silver, form which this 20 grams weight and 40 mm diameter coin was made of. The legend: "DEUTSCHLAND" és "EINIGKEIT RECHT UND FREIHEIT" is the non official motto of Germany, means "Unity, Justice, Freedom".
Extremely interesting is the next copper medallion, that was jointly issued by two cities, Zuffenhausen and La Ferte-sous-Jouarre for 20 year anniversary of their partnership, which happened actually in 1997. On the obverse is the town hall of Zuffenhausen, with the town hall square statue. Over the building is the comet. Maybe even the comet was visible from the city center or just an enthusiastic amateur astronomer alderman thought that the two events are linked. The Hale-Bopp returns next time in 4380 and the people at that time – even if the comet will be similarly spectacular - probably will find other cityscape. Legend around: "1872 - 1987 IM JAHRE DES KOMETEN HALE-BOPP", that is in the year of comet Hale-Bopp. Below: "125 JAHRE GEWERBE - U. HANDELSVEREIN", refers to the formation of business alliances in 1872.
On the revers the coat of arms of the two brother cities, their names and the year 1997 is shown. Legend around: "90 JAHRE STADTERHEBUNG", that is, became a city 90 years ago, at the bottom: "20 JAHRE PARTNERSCHAFT", that is partnership for 20 years.