Over the past 2.4 billion years, oxygen particles from the Earth's atmosphere have been streaming to the moon, researchers of a new study revealed.
Observations Of Japanese Lunar Orbiter Kaguya
Using data from studies of moon rocks and measurements taken by the Japanese lunar orbiter Kaguya, which was launched to study history, surface, and local gravitational environment of the moon, researchers found evidence that the moon may have materials that were produced by life from Earth as early as when plants started to fill the planet with oxygen.
Kaguya's sensors detected dramatic change in the kinds of oxygen ions that strike it whenever the lunar orbiter and the moon passed into the Earth's plasma sheet, a sheet-like region of denser hot plasma and lower magnetic field in the magnetosphere. It appears oxygen particles from Earth manage to stream to our planet's natural satellite.
Since most of the oxygen in the Earth's atmosphere is biological being produced by plants during photosynthesis, the moon, a dead rock with an environment that cannot support life, is showered with byproducts of life on Earth.
Evidence Oxygen From Earth Get To The Moon
Researchers have found several instances pointing to the presence of oxygen with Earthly origins in the lunar surface. Among this involves the isotope oxygen-16.
The sun produces highly charged material carried by solar winds that bombard the Earth and the moon. The Earth, however, is protected from these charged materials because of its magnetosphere. The moon, on the other hand, is more vulnerable leading to assumptions that the high-energy ions get buried in the lunar soil and thus the moon should have the isotopic signature that match the solar wind.
The Earth's upper atmosphere has relatively little oxygen-16 while the solar wind has more. One of the components of lunar soil is rich in oxygen-16, which means it is from the solar wind. Another component though is poor in oxygen-16.
It was not initially clear where this oxygen-16-poor component comes from until researchers compared this to the ions that are found in the Earth's atmosphere. Researchers said that the isotopic opposition of the oxygen-16-poor component is also quite the same as that of the ozone layer.
Another evidence that proves this oxygen originated from Earth is on how far the ions penetrated into the moon's soil. With about 1,000 electron volts, the ions from Earth fall into the same range as the oxygen ions found on the moon. The ions from the sun carried higher energies so they tend to penetrate deeper.
"We suggest the possibility that the Earth's atmosphere of billions of years ago may be preserved on the present-day lunar surface," study researcher Kentaro Terada of Osaka University, and colleagues wrote in their study, which was published in Nature on Jan. 30.
Researchers suggest that that the earthly oxygen ions may have come from the ozone layer where certain wavelengths of sunlight break apart the ozone into regular oxygen molecules and single atoms. The single atoms later get to the higher layers of the atmosphere where they eventually escape into space.