TOKYO - 'How was the moon born?' Among various hypotheses, the most supported is the 'Giant Impact Hypothesis.' This theory suggests that material from Earth forms part of the moon's interior. To investigate this, Japan's first successful lunar lander, SLIM, deliberately landed in a challenging area near a crater. The special camera onboard captured significant images. What does the analysis of these images reveal about the moon's origin?
The success of SLIM, Japan's first lunar lander, hinged on its landing location. It touched down on a slope near a crater, where rocks are abundant. The challenging landing site was chosen to fulfill the crucial mission of probing the moon's origin. Approximately 4.6 billion years ago, the solar system was formed from gas and dust in space. As the temperature, pressure, and density at the center increased, the sun was born. The remaining gas and dust collided to form planets like Earth. However, the exact formation process of the moon remains unclear.
Four major theories exist regarding the moon's origin. The 'Twin Theory' proposes that the moon and Earth formed simultaneously. The 'Parent-Child Theory' suggests the moon split from a part of Earth. The 'Capture Theory' posits that the moon formed elsewhere and was captured by Earth's gravity. The most supported theory, however, is the 'Giant Impact Hypothesis,' which suggests a Mars-sized body collided with Earth, causing material from Earth's mantle to scatter into space, eventually forming the moon.
To support the Giant Impact Hypothesis, it is crucial to confirm that the moon's internal materials are similar to Earth's mantle. The key is olivine, a mineral formed from cooled mantle material, which is also found around volcanoes on Earth. The presence of similar stones on the moon's surface, particularly around the crater where SLIM landed, is vital for this research. Craters form from meteorite impacts, scattering stones from the moon's interior around the impact site. SLIM was strategically positioned to examine these stones closely.
The research team marked ten stones captured by SLIM's special camera, naming them after dog breeds. The camera analyzes light wavelengths to identify the substances in the rocks. One stone, named 'Dalmatian,' was found to contain olivine. Further analysis of this olivine, comparing it to Earth's, could strengthen the Giant Impact Hypothesis. How close can we get to unraveling the moon's origin?
Source: TBS
