THE SUPERMOON: LUNAR SEA ON A GRAND SCALE
A supermoon is “the coincidence of a full moon or a new moon with the closest approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth”. These huge, bright moons are not particularly rare, but they are undoubtedly spectacular. The most recent occurrence was on July 12, 2014 and generated many wonderful images around the world, such as the header image (AP / D Mail) which cannily shows a shot from World Cup Land. The moon also brought a flurry of good photos from Abaco, for example these from Char Albury and Rhonda Pearce that were posted on FB. The visible detail of the moon’s surface is amazing – craters, seas, mountain ranges, lines and all. The source of radiance oddly appears to be a large crater I’d never heard of, called Tycho.
The event was a dream for selenologists (lunar scientists) and selenographists – those who study the surface and physical features of the Moon, and are involved in mapping and naming the lunar seas, craters, mountain ranges etc. A surprising amount of detail of the moon’s surface was visible even to the naked eye. Nowadays, orbiting spacecraft have made the scientific tasks much easier, and even the moon’s backside has been thoroughly charted (not to be confused with the frequent charting of The Dark Side of the Moon). In the UK we also noticed the phenomenon – a large, heavy moon hanging brightly in the sky. I took a few shots in the countryside where there is gratifyingly little light or air pollution, without thinking that the object I was focusing on was obviously much the same for everyone everywhere… Then I got to wondering what exactly I was looking at. I had a vague memory of some of the seas – Mare Imbrium for example – but I couldn’t remember any crater names at all. So I did a bit of research in an amateur serenographist kind of way and came up with this: This led me on to thoughts of the moon landings, and in particular Apollo 11. Wasn’t there something about touching down in the Sea of Tranquility? But whereabouts exactly on the supermoon? Here’s the answer. The moon below (from SOERFM) is at a different angle, but it can still be compared with the supermoons above. And what of all the other Apollo landings? Did they all aim for the same spot where Neil Armstrong staked his claim for mankind? Or were other landing areas tried by the Apollo moon missions? NASA has the answer: Then I wondered about the names given to the seas and craters. Are they all modern or are some historical? I came across a wonderful map that shows that many names were given and recorded centuries ago. The moon map below is confusing – it is upside down compared with all the ones above. However, it is clear that by the c17, the naming of lunar geographical features was already largely settled. Almost all the names I added to the moon above can be found on this map of 1647. Double-click on it to get an enlarged legible view. It’s worth noting that it was published only 5 years after Galileo’s death.
Photos: Charmaine Albury, Rhonda Pearce, RH, SOERFM, NASA; other credits as noted in text