NASA showed the "piece of the Moon" in Madagascar
NASA has published a space image of the Saririaky massif in southern Madagascar, which covers an area of nearly 100 square kilometers. It consists of anorthosite rock, which forms the bright mountainous regions of the Moon. However, this is not a fragment fallen from the Moon – the massif was formed on Earth itself.
NASA presented a "piece of the Moon" in Madagascar
The image shows a large, light-colored, rounded area among dark brown rocks. This is an outcrop of anorthosite rocks on the Earth's surface.
Anorthosite is an igneous rock formed as a result of the cooling of molten material underground, which preserves large mineral crystals. The Moon also has the exact same type of rocks: they form the bright mountainous regions that can be seen from Earth even without a telescope.
The Saririaky massif is not a new discovery. Geologists studied it long before the new orbital images were taken.
In 1998, researchers led by Lewis Ashwal estimated the crystallization age of the anorthosites in Saririaky and the neighboring Ankafotia massifs to be approximately 660 million years. The margin of error in the calculation was 60 million years.
For this, scientists used the ratio of samarium and neodymium isotopes in the rocks and individual minerals. According to the analysis, the original molten material that formed the rocks originated from the Earth's mantle.
Later, these rocks underwent intense changes under the influence of high temperature and pressure. Researchers associated this process with the collision of the eastern and western parts of Gondwana approximately 630–550 million years ago. This supercontinent included the territories of present-day Africa, India, Madagascar, Australia, and Antarctica.
Traces of ancient deformation are also observed in the elongated rock layers around the massif. In a 2000 study, scientists identified two stages of changes in this area — periods approximately 590–530 and 530–500 million years ago.
The anorthosites on the Moon, however, are much older than those in Madagascar: their age exceeds four billion years. According to the model of the Moon's early magma ocean, light plagioclase crystals floated to the surface of the molten material, accumulated, and formed the outer crust. Heavier minerals sank deeper.
Participants in the Apollo program brought samples of such ancient rocks back to Earth. One of them is sample number 15415, known as the "Genesis Rock," found by the Apollo 15 astronauts on August 1, 1971. Its age was estimated at approximately four billion years.