Table of Contents
The Moon’s Formation: Insights from Apollo 17 Samples
Introduction
The crescent Earth rises above the lunar horizon in this undated NASA handout photograph taken from the Apollo 17 spacecraft in lunar orbit during the final lunar landing mission in the Apollo program in 1972.
| Photo Credit: Reuters
During the Apollo 17 mission in 1972 – the last time people walked on the moon – U.S. astronauts Harrison Schmitt and Eugene Cernan collected about 243 pounds (110.4 kg) of soil and rock samples that were returned to Earth for further study.
A half century later, crystals of the mineral zircon inside a coarse-grained igneous rock fragment collected by Schmitt are giving scientists a deeper understanding about the moon’s formation and the precise age of Earth’s celestial partner.
The moon is about 40 million years older than previously thought – forming more than 4.46 billion years ago, within 110 million years after the solar system’s birth, scientists said on Monday, based on analyses of the crystals.
Significance of Apollo 17 Samples
The Apollo 17 samples provide invaluable information about the moon’s formation and its relationship to the Earth. By studying the crystals of zircon found in the samples, scientists are able to determine the moon’s age with greater precision.
Features and Objectives
The leading hypothesis for lunar formation is that during the solar system’s chaotic early history, a Mars-sized object called Theia collided with primordial Earth. This impact caused magma, or molten rock, to be ejected into space, forming a debris disk that eventually coalesced to form the moon. The objective of studying the Apollo 17 samples is to confirm the timing and process of this moon formation event.
Effects of the Study
By establishing the moon’s formation date, scientists can better understand the impact it has had on Earth’s rotational speed and stability. The moon’s formation played a crucial role in stabilizing Earth’s axis and creating a habitable environment. Additionally, the moon’s gravitational pull influences ocean ecosystems and helps shape our climate.
Pros and Cons
The study of the Apollo 17 samples and the insights gained from them have several benefits. It allows us to understand our solar system’s history, gain knowledge about the moon’s geology, and lay the groundwork for future deep-space explorations. However, the availability of a limited number of Apollo samples restricts the scope of research and requires scientists to make the most of the available resources.
Fun Fact
All the oldest minerals found on Earth, Mars, and the moon are zircon crystals. Zircon, a durable mineral, provides valuable information about the history of celestial bodies and their formation.
References:
- The Hindu – Moon formed 4.44 billion years ago, 40 million years earlier than thought: Researchers
- NASA – Moon (Natural Satellite)
Mutiple Choice Questions
1. What mission collected soil and rock samples from the moon?
a) Apollo 11
b) Apollo 12
c) Apollo 17
d) Apollo 20
Explanation: The correct answer is c) Apollo 17. During the Apollo 17 mission in 1972, U.S. astronauts Harrison Schmitt and Eugene Cernan collected about 243 pounds of soil and rock samples from the moon.
2. What mineral were scientists able to find inside a rock fragment collected during the Apollo 17 mission?
a) Quartz
b) Zircon
c) Diamond
d) Feldspar
Explanation: The correct answer is b) Zircon. Scientists were able to find crystals of the mineral zircon inside a coarse-grained igneous rock fragment collected by Harrison Schmitt during the Apollo 17 mission.
3. How old is the moon based on the analysis of zircon crystals?
a) Approximately 40 million years old
b) Approximately 4.46 billion years old
c) Approximately 110 million years old
d) Approximately 51 years old
Explanation: The correct answer is b) Approximately 4.46 billion years old. Based on the analysis of zircon crystals found in a rock fragment collected during the Apollo 17 mission, scientists determined that the moon formed more than 4.46 billion years ago, within 110 million years after the solar system’s birth.
4. What is the leading hypothesis for lunar formation?
a) Impact of a meteor
b) Volcanic eruption
c) Collision with another planet
d) Gradual accretion of space debris
Explanation: The correct answer is c) Collision with another planet. The leading hypothesis for lunar formation is that a Mars-sized object called Theia collided with primordial Earth, blasting magma into space. This magma eventually coalesced into the moon.
5. What method was used to confirm the age of the zircon crystals?
a) Atom probe tomography
b) Ion microprobe analysis
c) Radiocarbon dating
d) Carbon-14 analysis
Explanation: The correct answer is a) Atom probe tomography. Scientists used atom probe tomography to confirm the age of the zircon crystals found in the rock fragment collected during the Apollo 17 mission. This method helped determine that there were no complications involving the lead atoms, confirming the age of the crystals.
6. How does the moon stabilize Earth’s axis and rotational speed?
a) By exerting gravitational pulls on Earth
b) By absorbing excess heat from Earth
c) By regulating ocean currents
d) By emitting low-frequency vibrations
Explanation: The correct answer is a) By exerting gravitational pulls on Earth. The moon’s gravitational pulls help stabilize Earth’s rotational axis and slow down its rotational speed. This stabilization is important for maintaining a stable climate on Earth.
7. How does the moon contribute to future deep-space explorations?
a) By providing a stable climate for space travel
b) By serving as a stepping stone for space missions
c) By supplying resources for space missions
d) By supporting human cultures and inspirations
Explanation: The correct answer is b) By serving as a stepping stone for space missions. NASA and other space agencies view the moon as a stepping stone for future deep-space explorations. The moon’s proximity to Earth makes it an ideal location for testing technologies and conducting research before venturing further into space.
Brief Summary | UPSC – IAS
The moon is about 40 million years older than previously thought, forming more than 4.46 billion years ago, according to a study based on an analysis of crystals of the mineral zircon collected by U.S. astronauts during the Apollo 17 mission in 1972. The findings provide scientists with a deeper understanding of the moon’s formation and the precise age of Earth’s celestial partner. The study used atom probe tomography to confirm the age of the zircon crystals, which were found in a rock fragment collected from the moon’s surface. The moon’s formation is believed to have resulted from a giant impact between Earth and a Mars-sized object called Theia.