Lunar water is water that is present on the Moon. It was first discovered by NASA’s Apollo 14 mission in 1971. The Moon as Earth’s satellite has been the focus of space exploration since the dawn of the space age. Man first set foot on the surface of our neighboring planet on july 20th 1969. During the first manned lunar landing of apollo 11 the detection of water is of fundamental importance.
As a building block of life it could have enabled extraterrestrial beings. But also plays an important role in further space exploration as well as in proposed colonies on the moon. This blog gives you information of various research programs over the past decades that led to the detection of water on the Moon.
Research programs of the 20th century
As early as 1961 researchers watson murray and brown of the california institute of technology speculated about the existence of water on the moon. As a result of the apollo program rock samples were collected by astronauts and brought back to earth.
In which investigations revealed traces of water at that time the research assumed the moon rock had been contaminated. Since the surface of the moon was considered at that time completely dry.
In march 1971 during the apollo 14 space mission the first direct evidence of water was detected. When the mass spectrometer of the space capsule registered the emission of water vapor ions from the lunar surface near the landing site of apollo 14.
Scientists Markov, Akmanova and Dementev from the vernaski institute of geochemistry and analytical chemistry published a paper in february 1978 in which they formulated the discovery of water with quite certainty. Their studies were based on lunar rocks brought to earth by the luna 24 spacecraft in 1976. In which a very small amount of water was detected by spectroscopic examination.
Another indication of ice on the moon came in 1994 from the clementine spacecraft, a joint project of nasa and the ballistic missile defense organization. Clementine used radio waves to investigate the regions at the south pole of the moon.
These waves were picked up on earth by the dish antennas of the deep space network.( A global research network of satellite dishes for communication with satellites and space probes). Although the polarization of the waves was characteristic of an icy surface.
The test results remained inconclusive and were therefore questioned. Radio surveys from earth identified an area around the moon’s poles that is permanently in shadow and therefore there is a chance that there are ice deposits in an area of 8700 square miles. The lunar prospector spacecraft launched in 1998 was able to conduct further investigations with its measuring instruments.
It had a neutron spectrometer and was thus able to measure the amount of water vapor in loose lunar rock also called Regolith in the polar regions of the moon. In this way hydrogen in the range of 50 ppm parts per million and an increased hydrogen concentration at the poles of our neighboring planet could be detected.
Researchers interpret the results as evidence for hydrogen bound in minerals or ice in the always overshadowed lunar craters. Nasa researchers estimate the expected amount of ice on the moon at 0.6 to 1.9 cubic miles. And base of their statements on the results obtained by the clementine and lunar prospector probes.
At the end of the lunar prospector’s mission it was allowed to fall purposefully into the shoemaker crater. The scientists hoped for new discoveries in such a way the crater is located near the south pole of the moon and the crash was supposed to release measurable amounts of hydrogen.
The last exploration of the moon satellite in the last millennium was on August 18 1999 during a flyby of the cassini-huygen spacecraft which provided incomplete data and no new information about water on the moon.
Research programs of the 21st century
After the turn of the millennium observation of the moon by the deep impact spacecraft continued in 2005 and experienced a setback due to incomplete data regarding the presence of water on the moon.
Radar investigations by the meanwhile demolished arecibo observatory in Puerto Rico in 2006 showed that the findings by the Clementine probe could not be ice but rock fragments.
This would also put the evidence ofwater vapor from the lunar prospector spacecraftin a different light and suggest a source other than ice for the water vapour. The data from the arecibo observatory nevertheless offers room for interpretation for the existence of water in the craters lying in the shadow of our Moon.
This assumption was confirmed by the measurements of bound hydrogen during the next flyby of deep impact in 2009. Only the probe of the Indian spacecraft Chandrayaan-1 which was brought down in a controlled manner in shackleton crater in november 2008 was able to provide clarity.
On its 25-minute descent the probe’s altitudial composition explorer detected water in the thin atmosphere of the earth’s moonand hydroxyl absorption and reflected sunlight.
NASA confirms the existence of water on the Moon
On september 25th 2009 NASA announced that water is present in large regions on the surface of the moon. The deposits are small concentrations of hydroxyl groups bound in the soil of our neighboring planet.
The findings are based on measurements made by the cassini-huygens and deep impact probes with their spectrometers over the last century and by the moon mineralogy mapper on the Indian spacecraft chandrayaan-1. On images from the Moon mineralogy mapper the spectral signature of hydroxide is indicated by blue areas.
The reflected infrared radiation from the sun shows the brightness of the lunar surface and is indicated by green areas on the imagery. Red areas on the photos taken by the moon mineralogy mapper indicate the existence of the mineral pyroxene.
Although the measuring results are consistent with those of the measuring instruments on board Chandrayaan-1. and show water molecules in the regions around the poles of the Moon. Thick ice layers below the lunar surface cannot be assumed. It is much more likely that they are pieces of ice about four inches thick associated with the loose lunar rock layer the regolith.
Additional results by the moon mineralogy mapper were published by NASAin 2018 and suggest ice deposits around both poles. In addition the moon mineralogy mapper’scapabilities to measure absorption in the overshadowed regions of the moon were used to detect ice on the moon.
The measurement results show that the ice is concentrated in smaller patches at the north pole but is distributed in a larger ice surface at the south pole. In march 2010 radar surveys aboard Chandrayaan-1 detected more than 40 craters lying in shadow in the region around the moon’s north pole that could hold up to 600 million tons of ice.
Read also : The 20 Most Amazing Planets Ever Found!
Circulation of water on the Moon
Scientists believe that water on the moon may have two different origins –
One theory is that water arrived on the moon through comets or other celestial bodies that carried water in the rock layers.
The other view assumes a local origin and sees the protons in the solar winds undergoing a chemical reaction with the hydrogen atoms in the lunar rocks. Which as a result binds small amounts of hydroxyl groups in the minerals. These hydroxyl groups consist of one part water and one part oxygen which are formed by the reaction with a hydrogen proton with oxygen atoms.
They oxidize on the surface and could convert the water molecules by absorption.
Water rights on the Moon
There remains the question of property rights regarding water deposits on the moon. The united nations outer space treaty does not have a clause regarding exploitation of resources on alien planets. However it does not allow a country to claim local resources on planets in our solar system.
Another risk for the plundering of resources comes from the private sector through well-funded companies that seize and exploit the available raw materials in their endeavors inspace. These companies see the resources as aprofit which they obtain at entrepreneurial risk by using their own financial resources.
To counteract this however the moon treaty was created, it aims to prevent the exploitation of the moon’s resources and gives the international communityequal ownership rights without privileging any countries companies or people.
The moon treaty provides for the peaceful use of the celestial bodies and is intended to prevent military presence in space. The treaty was presented to the united nations in 1979 and ratified by only 17 countries in 1984.
The United States of America in particular had been critical of the moon treatyarguing that it jeopardizes the free right to profit.Overall the treaty is considered a failure due to the small number of signatory states. On earth there have been conflicts over raw materials and influence since the existence of mankind.