Mond No. Mare Orientale on the Lunar surface
by Detlev van Ravenswaay - Detlev van Ravenswaay - © Detlev Van Ravenswaay/Science Photo Library/Corbis
Moon's surface. At centre is the Mare Orientale, a multi-ring basin formed by a massive asteroid impact that then filled with lava. Its position is half on the lunar near side and half on the lunar far side.
Mare Orientale is a multi-ring basin half the size of the Mare Imbrium. It was formed by a massive asteroid impact which filled with lava. Its position is half on the near side south-west and half on the lunar far side. Estimated impact time - one billion years to several 100 million years.