Moon Rocks

The words

1. Anorthosite

   A rock made chiefly of feldspar crystals.

   Light-colored anorthosite helped scientists reconstruct the Moon’s early crust. NASA describes this rock crystallizing from molten material and floating upward, leaving evidence of an ancient ocean of magma.

   NASA: lunar rock types (opens a new tab) · NASA: how lunar rocks inform Moon origins (opens a new tab)

2. Big Bertha

   Big Bertha was Apollo 14 sample 14321, collected near Cone Crater. NASA’s 2021 account described one embedded fragment as possible ancient Earth material carried to the Moon by an impact.

   NASA: sample 14321, Big Bertha (opens a new tab) · NASA: a possible Earth fragment (opens a new tab)

3. Big Muley

   Big Muley was sample 61016, the largest individual rock returned by the Apollo astronauts. NASA compared its size with an American football, giving readers a familiar sense of its scale.

   NASA: sample 61016, Big Muley (opens a new tab)

4. Breccia

   A rock assembled from fragments of earlier rocks.

   Meteorite impacts broke lunar rocks apart and welded fragments into new rocks. Apollo breccias preserved those collisions within their mixed pieces, rather than recording only a single episode of cooling.

   Did you know?

   Big Bertha contained fragments of smaller breccias within the larger rock. Its mixed pieces gave researchers a record of earlier rocks incorporated into a later one.

   NASA: lunar rock types (opens a new tab) · NASA: sample 14321, Big Bertha (opens a new tab)

5. Curator

   NASA’s sample-curation staff preserved lunar material together with its records. They prepared portions for approved research and education, keeping returned research material separate from samples maintained in pristine condition.

   NASA: preserving lunar samples (opens a new tab)

6. Giant Impact

   The giant-impact theory linked the Moon’s origin to a collision with the young Earth. Apollo sample chemistry and evidence of early melting helped scientists investigate how that collision might have formed the Moon.

   NASA: how lunar rocks inform Moon origins (opens a new tab)

7. Glovebox

   Lunar samples were handled inside stainless-steel glove cabinets filled with high-purity nitrogen. Built-in gloves separated human hands from the material, helping preserve the samples for scientific work.

   NASA: preserving lunar samples (opens a new tab)

8. Goodwill Rocks

   In March 1973, President Nixon directed that fragments of Apollo 17 sample 70017 be distributed as goodwill gifts. The recipients included U.S. states and territories and foreign heads of state.

   NASA: Apollo 17’s goodwill gifts (opens a new tab)

9. Lunar Samples

   The six Apollo landing missions returned rocks, soil, pebbles and core samples from different lunar sites. Studying that material on Earth gave scientists evidence about the Moon’s crust, impacts and volcanic history.

   NASA: the Apollo sample collection (opens a new tab)

10. Magma Ocean

    The young Moon was thought to have had a deep layer of molten rock. Anorthosite and other sample evidence helped scientists reconstruct how this magma ocean cooled and formed an early crust.

    NASA: how lunar rocks inform Moon origins (opens a new tab)

11. Rake

    The lunar rake separated pebbles from finer soil. Apollo 17’s geology tools also included scoops for gathering soil and tongs for picking up individual rocks, giving the crew different ways to collect samples.

    Did you know?

    Extension handles attached to the geology tools let astronauts reach the ground while standing. They could collect samples without having to bend all the way down.

    NASA: Apollo’s geology tools (opens a new tab)

12. Touch Rock

    The Smithsonian’s lunar touchrock was cut from a basalt collected during Apollo 17. Prepared as a public exhibit, the slice let visitors feel a piece of material brought back from the Moon.

    Did you know?

    The museum’s touchable Moon-rock exhibit opened in 1976. Its small slice came from the largest rock that the Apollo 17 crew brought home.

    Smithsonian: the lunar touchrock (opens a new tab)

13. Vesicles

    Hollows left by gas bubbles in rock as it solidifies.

    Apollo 17 sample 76015 contained vesicles formed when gas bubbles were trapped in molten rock after an impact. Its cavities recorded that melting history, unlike the tiny impact scars on its surface.

    Lunar Surface Journal: holes in Moon rocks (opens a new tab)

14. Volcanic Glass

    Apollo 17’s orange soil near Shorty Crater contained particles of volcanic glass. Laboratory examination on Earth identified the glass that gave the collected soil its distinctive orange color.

    NASA: orange volcanic glass (opens a new tab)

15. Zap Pits

    Tiny particles striking exposed lunar rocks blasted small craters called zap pits into their surfaces. On sample 76015, pale areas around these pits marked rock shattered by the impacts.

    Lunar Surface Journal: holes in Moon rocks (opens a new tab)