Why in the News?

Scientists long believed that volcanic activity on the moon ceased about a billion years ago.
- However, a study based on China’s Chang’e-5 mission samples has questioned this belief with evidence suggesting the moon had active volcanoes as recently as 120 million years ago.

Chang’e-5 Mission: Overview and Recent Findings

Chang’e-5 is a mission launched in November 2020 as part of the Chang’e lunar exploration program.
It was designed to:
- Collect samples from the moon’s surface and bring them back to Earth for analysis.
- Study the geology and mineral composition of the moon.
It successfully landed on the “Mons Rumker region”, a volcanic complex in the Oceanus Procellarum (the ‘Ocean of Storms’) area on the moon’s near side, and returned about 1.7 kg of lunar material to Earth in December 2020.

Recent studies of samples have revealed evidence of volcanic activity on the moon as recently as 116-135 million years ago.
- It challenges the previous belief that the moon’s volcanic activity ceased about a billion years ago.
The analysis of lunar glass beads collected by Chang’e-5 has provided insights into both volcanic eruptions and asteroid impacts that shaped the moon’s surface.

Lunar glass beads are small, spherical or egg-shaped glass particles found on the moon’s surface.
These beads are formed in two main ways:

- Volcanic Activity: During volcanic eruptions, molten lava fragments are thrown into the air, where they cool rapidly and form glass beads.
- Impact Events: When asteroids or meteorites hit the moon’s surface, the intense pressure and heat melt the surface material. The molten material cools quickly, forming glass beads as it lands back on the surface.

- Provide clues about the moon’s geological history.
- Help scientists determine the age of volcanic eruptions.
- Offer insights into the formation of the moon’s surface and its volcanic and impact events.

Composition: These beads are primarily made of silicon, magnesium, and iron, with trace amounts of other elements such as potassium, titanium, and uranium.
Volcanic vs. Impact Beads: Volcanic glass beads tend to be more uniform, while impact beads may show fractures or deformations caused by high-energy impacts. Volcanic beads often contain more volatile elements like sulphur, which are released during eruptions.

[2012] What do you understand by the term Aitken basin?

(a) It is a desert in the southern Chile which is known to be the only location on earth where no rainfall takes place.

(b) It is an impact crater on the far side of the Moon.

(d) It is a deep hyper saline anoxic basin where no aquatic animals are found.