On Dec. 17, 2020, the Chang'e 5 return capsule was seen at its landing site in Inner Mongolia (China),
According to new research, China's moon-rock treasure trove could be one billion years older than material that the Apollo program brought back decades ago.
In December, China's Chang'e 5 spacecraft returned 3.81 pounds (1.73 kg) of moon rocks from Oceanus Procellarum back to Earth scientists. Scientists who have access to the valuable material have been conducting a variety of experiments since then to discover the mysteries of the solar system and to better understand the rocks.
The spacecraft appears to have found the perfect sample to fill the gap in science's knowledge, according to a new study. Two pieces of newly returned lunar rock have been dated at approximately 1.97 billion years, plus or minus 50 million years.
Brad Jolliff, a NASA planetary scientist and co-author of the new research that was conducted by a Beijing-based team, stated in a statement, "It's the perfect sample to close the 2-billion-year gap."
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This gap spans from approximately 3 billion years ago when most of the rock in the Apollo samples formed to around a billion years before some young, dateable impact craters formed.
Scientists have used these time-stamped samples to determine relative ages using crater dating, in an attempt to unravel the solar system's 4.5 billion-year-old history. "Planetary scientists have discovered that the older a surface is, the more craters it has. The younger the surface, according to crater dating. Jolliff stated that this is a good relative determination. "But, to assign absolute age dates to that, one must have samples from these surfaces."
Scientists could use this approach to determine the number of craters present at Apollo's source. This could be used by planetary scientists to estimate the date of other, just as-battered surfaces on the moon and across the solar system on worlds that scientists have not been able access.
Scientists' crater-dating timeline was missing lunar samples between 3 billion to 1 billion years ago. This long gap meant that scientists could not even estimate the ages of surfaces during this time.
Even with these tiny rocks (0.1 to 0.15 inches in size), Chang'e 5 helped to fill the hole.
Jolliff stated that the study yielded a precise age of 2 billion years plus or minus 50,000,000 years. It's an amazing result. It's a precise determination in terms of planet time.
It is important to know the age of these samples, as they are a kind of rock called basalt. This type of rock forms during volcanic eruptions. Scientists previously had no evidence of lava flowing onto the moon until 3 billion years ago.
Because the lunar crust is thin and rich in elements that generate heat, the scientists expected to find some of the youngest basalts from the region. Researchers aren't sure how the rock was molten to this point.
These results were described in a paper published in Science on Thursday, Oct. 7.
Send Meghan Bartels an email at mbartels@space.com, or follow her Twitter @meghanbartels. Follow us on Facebook and Twitter @Spacedotcom
