Beatles in Outer Space?

With the advent of the year 2000, I thought I would look up the name of the minor planet numbered 2000 and see if there was anything special about it. There certainly is for it was named for William Herschel, the discoverer of the first telescopic major planet. Minor planet (1000) Piazzi also has some special significance as it is named in honour of Guiseppe Piazzi who discovered the first minor planet. The Times magazine’s "person of the century" , Albert Einstein has been honoured by having minor planet (2001) named for him. Minor planet studies go back almost 200 years.

The object (1) Ceres was discovered on January 1st 1801. Number 7039 (unnamed) was discovered on April 14th 1996. In the 10 years up to 1996 as many minor planets were discovered as in the previous 185 years. And since then thousands more have been discovered, many by amateurs with small backyard telescopes. It is estimated that there may be as many as 300,000 objects out there in the region of our solar system lying roughly between the orbits of Mars and Jupiter.

The history of the naming of minor planets is quite interesting. Until the middle of the nineteenth century the convention was to use names from classical Greek mythology - following on from "Uranus", and "Neptune", the "modern" planets ( Pluto was to come much later),. The major planets were often referred to by symbols, those ones we sometimes see on astrological charts these days. Inventing symbols that were universally recognisable for the newly discovered minor planets was a huge problem and so a numbering system was adopted. Ceres, Pallas, Juno and Vesta were mentioned in scientific literature without associated numbers. They were handled in the same way as the major planets of the time. Ferguson in 1852 initiated the use of ordinal numbers instead of symbols with (16) Psyche. He used an encircled number rather than setting the number in parentheses as is practised today. By the end of the year 1857 some 50 planets had been discovered.

Ceres, Pallas, Juno and Vesta are names taken from classical mythology. The name given to minor planet (12) Victoria was the first of many to initiate a long controversy. It was thought to have been chosen to honour the reigning monarch, queen Victoria, and was thus rejected in some quarters. The use of non classical names was severely criticised. After about 400 minor planets had been discovered the supply of classical names became exhausted and astronomers resorted to a new convention - that of using female names. Why female names is not clear.

The BAJ (British Astronomical Journal) requested that " there is reason to ask the discoverers not to deviate from the rule of choosing female names . Male names will not be accepted by the BAJ". The one exception to this rule seems to have been the naming of the "Trojan" planets.

Objects involved with the Jovian triangular libration points are named in accordance with the traditions of honouring heroes of the Trojan war, the Greek besiegers and their Trojan counterparts. They were given male names in contrast to the normal female planets

The Trojan planets move in an orbit around the sun at about the same distance as Jupiter but 60 degrees ahead of and 60 degrees behind Jupiter.

Discoverers sought to get round the restriction of only using female names by adding the feminine suffix ‘-a’ or ‘-ia’ to non-feminine names. Thus cities and male names were transformed in this way to follow the rule. And so you have, for example, (416) Vaticana and (434) Hungaria. This convention seems to have ended around World War II.

After the end of World War II the rule of assigning names with female endings was finally changed and today you have very relaxed naming rules. There is one rule however that seems to be applied quite strictly - names glorifying people or events that had primarily a political or military nature will not be accepted until at least 100 years after the death of the person or the occurrence of the event.

Although there are many numbered minor planets that have not yet received names there is only one minor planet that received a name but not a number. It is Hermes, discovered October 28th 1937 at Heidelberg in Germany. It was very near earth, moving quite quickly, at an hourly rate of 20 minutes of arc, on the night of discovery. It passed from opposition to conjunction in only 2 days and passed 0.005 a.u. from Earth on October 30. Unfortunately the planet was lost soon after this and has not been seen since.

146 minor planets were discovered at the Observatory in Johannesburg. The first one was number (715) Transvaalia found on April 22nd 1911 by H E Wood. It is interesting to speculate what instrument was used at the time. One possibility is the Franklin-Adams camera/telescope which is now at Broederstroom. Two more were discovered in 1912, (790) Pretoria and (758) Mancunia (the Latin name for the city of Manchester, Wood’s home town). There was then quite a gap to the next discovery on May 21 1922 when (982) Franklina was found. It is named after John Franklin-Adams, whose one telescope, the 6-inch/7-inch refractor, we use in the Papadopoulos dome. His other telescope was a 10-inch F4.5 refractor, designed for photography, which was used extensively at the Union observatory. The observatory itself is honoured by the naming of minor planet (1585) Union , discovered in 1947 by E L Johnson at Johannesburg. Minor planet (1925) Franklin-Adams also honours our benefactor.

And then I saw the reference to minor planets (4147), (4148), (4149), (4150). They are named Lennon, Macartney, Harrison and Starr. We used to know these guys as John, Paul, George and Ringo and rock ‘n roll to their music all night. Now you can spend all night looking for these little rocks that roll around space, named after them.

Brian Fraser