The International Astronomical Union (IAU) have approved new names for features discovered on the planet Mercury. These newly named features were discovered on the images taken by the MESSENGER spaceprobe during its Mercury flyby in January 2008. Rules for naming exist for the majority of the features on planets, the moons, and the asteroids. The Mercury cliffs are named after the boats of famous explorers. Cliffs discovered by MESSENGER (rupes, Latin for cliffs) have been called Beagle Rupes, after the name of the boat on which the naturalist Charles Darwin sailed around the world. Craters: Apollodorus, Atget, Cunningham, Eminescu, Kertész, Neruda, Raditladi, Sander, Sveinsdóttir, Xiao Zhao Rupes: Beagle Rupes Fossae: Pantheon Fossae Read more
Pantheon Fossae is that spider like feature of crevices along the Mercury surface This is by the way official site of the Messenger probe sent to Mercury: http://messenger.jhuapl.edu/
Check it out: Pantheon Fossae, the spider feature as they call it in Caloris Basin Please Register or Log in to view the hidden image!
they are names from mythology...in future colonists if there are such and astrologers will have an easier time remembering these names because of mythological connections. Also it will add a graphical context to a bleak grotesque nature of some on the planets and moons...especially Mercury that has not much to offer.
I would expect only minimal changes in orbit, an increase equilivant to the mass of Mercury. Remember also the Sun will be less massive at this point. But I would expect a big splash effect which I would not want to be proximal too.