Lunar and Planetary Institute

Apollo 11 Mission

Lunar Sample Overview

Apollo 11 basalt 10049Apollo 11 basalt 10049. This sample has a mass of 193 grams and is up to 10 centimeters across. (NASA/Johnson Space Center photograph S76-25456.)



Apollo 11 breccia 10018Apollo 11 breccia 10018. This sample has a mass of 213 grams and is up to 8 centimeters across. (NASA/Johnson Space Center photograph S75-30226.)



Apollo 11 carried the first geologic samples from the Moon back to Earth. In all, astronauts collected 22 kilograms of material, including 50 rocks, samples of the fine-grained lunar "soil," and two core tubes that included material from up to 13 centimeters below the Moon's surface. These samples contain no water and provide no evidence for living organisms at any time in the Moon's history. Two main types of rocks, basalts and breccias, were found at the Apollo 11 landing site.

Basalts are rocks solidified from molten lava. On Earth, basalts are a common type of volcanic rock and are found in places such as Hawai'i. Basalts are generally dark gray in color; when one looks at the Moon in the night sky, the dark areas are basalt. The basalts found at the Apollo 11 landing site are generally similar to basalts on Earth and are composed primarily of the minerals pyroxene and plagioclase. One difference is that the Apollo 11 basalts contain much more of the element titanium than is usually found in basalts on Earth. The basalts found at the Apollo 11 landing site range in age from 3.6 to 3.9 billion years and were formed from at least two chemically different magma sources.

Breccias are rocks that are composed of fragments of older rocks. Over its long history, the Moon has been bombarded by countless meteorites. These impacts have broken many rocks up into small fragments. The heat and pressure of such impacts sometimes fuses small rock fragments into new rocks, called breccias. Many fragments can be seen in the breccia photograph shown above. The rock fragments in a breccia can include both mare basalts as well as material from the lunar highlands. The lunar highlands are primarily a light-colored rock known as anorthosite, which consists primarily of the mineral plagioclase. It is very rare to find rocks on Earth that are virtually pure plagioclase. On the Moon, it is believed that the anorthosite layer in the highland crust formed very early in the Moon's history when much of the Moon's outer layers were molten. This stage in lunar history is known as the magma ocean. The plagioclase-rich anorthosite floated on the magma ocean like icebergs in the Earth's oceans.

Collecting Moon Rocks
This document describes the tools and procedures used by the Apollo astronauts to collect lunar samples.