Ice recently discovered water on the bottom of a crater near the moon's south pole is accompanied by metallic elements such as mercury, magnesium, calcium and trace amounts of silver. Now you can add to the mix also sodium, according to Dr. Rosemary Killen of the NASA Goddard Space Flight Center.
The recent discovery of significant deposits of water on the moon were nothing short of amazing geological view of its troubled history. Heavy bombardment by asteroids in the first phase of his life and because of its weak gravity and the strong solar radiation, has been deprived of almost all of its atmosphere.
This made the lunar surface dry and arid.
However, due to the orientation of the Moon from the Sun, scientists have theorized that the cluster would deep craters in permanent shadow, and then very cold, so as to retain volatile substances like water from cometary impacts or chemical reactions with hydrogen, one of the main components of the solar wind.
On 9 October 2009, NASA's Lunar Crater Observation of the impact and Sensing Satellite (LCROSS) in the region permanently shadowed crater Cabeus confirmed that a surprisingly high number of water ice is present together with small amounts of many other elements, including metal.
LCROSS was launched June 18, 2009 as a mission partner of the NASA Lunar Reconnaissance Orbiter, or LRO, the NASA Kennedy Space Center in Florida. After separating from LRO, LCROSS probe has entered a series of orbits around the Earth.
After driving for about 113 days nearly 5.6 million miles (9,000,000 kilometers), LCROSS and the Centaur rocket split over the impact on the moon and reach the ground and explode, LCROSS and LRO spacecraft observed with their instruments board. Were collected about four minutes of data from the first impact with the LCROSS lunar surface.
Killen and his team looked at the impact of the LCROSS Solar Telescope McMath-Pierce at the National Solar Observatory in Tucson, Arizona. They are
were the only team able to see the results of the impact from the ground.
impacts have vaporized material from the crater floor Cabeus, including water and sodium. After the steam plume rose to about 800 meters (about 2,600 meters) high enough to remove the shadow from the edge of the crater, the sun's light has stimulated the sodium atoms, causing them to issue a yellow-orange glow. A high resolution spectrometer, Echelle, attached to the telescope has detected this unique glow. The instrument separates light into its colors and pressed to identify those materials issued by the colors when excited by radiation or by other events in space.
The spectrometer observed the sky through a narrow slit to separate the colors, but the team then had to assume the shape and temperature of the plume and estimated the total amount of sodium released from the impact. Using a computer model and data from other instruments on LRO and LCROSS, the team calculated that have been issued by one to two kilograms (about 2.2 to 4.4 pounds) of sodium.
"This is the 1-2 per cent of the amount of water released from the impacts," said Killen. "Our oceans have a comparable amount of sodium to water ratio, about one per cent" (The amount of ash depends on the temperature derived from observations taken steam).
The presence of these large amounts of sodium raises the question whether it can be reached on the lunar surface by cometary impacts and then trapped in permanently shadowed regions, where it was then frozen.
The solar wind carries small amounts of sodium, which could have become an integral part of the lunar surface and may have been released from lunar rocks, which own about 0.4 percent sodium. Sodium may also have been released from lunar rocks by impacts of meteoroids. (LCROSS impacts do not have enough energy to vaporize the rock, so it is unlikely that the plume of sodium vapor is just came from rocks at the impact site, according to Killen).
"The two percent sodium water is consistent with the amount of sodium in comets, so maybe most of the sodium and water from cometary impacts," said Killen. Although only a 'hypothesis, it is possible that comes from a different source or even from a variety of sources, including lunar volatiles trapped in the cold by chemical processes with the interaction of the solar wind with the surface. "The best evidence for a cometary origin could only be an analysis of isotopes of hydrogen lunar water, concludes Killen.
Isotopes are versions of an element with different weights, o masse. Ad esempio, un atomo di deuterio è una versione più pesante di un atomo di idrogeno comune, perché ha una particella extra, un neutrone, nel suo nucleo centrale. Il deuterio può essere sostituito con l'idrogeno in una molecola d'acqua, ma è molto meno comune e la sua concentrazione varia nel Sistema Solare. Se il deuterio è nello stesso rapporto con l'idrogeno presente nel ghiaccio delle comete, è possibile l'acqua provenga da impatti cometari.
Dal momento che le comete sono come "palle di neve sporca", vorrebbe dire che gran parte del sodio e di altri composti volatili provengono proprio dalle comete.
Il team prevede di far luce sull'origine delle acque lunar and other volatile compounds using the data of the next mission Lunar Atmosphere and Dust Environment Explorer (LADE), which should be launched in May 2013.
The mission will enter into lunar orbit to observe its tenuous atmosphere (exosphere technically called because it is so thin that atoms rarely collide with each other above the surface).
The research was funded by the NASA Dynamic Response Environment (dream) of the Moon project.
The McMath-Pierce telescope is operated by the National Solar Observatory, which is funded by the National Science Foundation and operated by the Association of Universities for Research in Astronomy. The scientific report on this research was published in Geophysical Research Letters in December 2010.
This made the lunar surface dry and arid.
However, due to the orientation of the Moon from the Sun, scientists have theorized that the cluster would deep craters in permanent shadow, and then very cold, so as to retain volatile substances like water from cometary impacts or chemical reactions with hydrogen, one of the main components of the solar wind.
On 9 October 2009, NASA's Lunar Crater Observation of the impact and Sensing Satellite (LCROSS) in the region permanently shadowed crater Cabeus confirmed that a surprisingly high number of water ice is present together with small amounts of many other elements, including metal.
LCROSS was launched June 18, 2009 as a mission partner of the NASA Lunar Reconnaissance Orbiter, or LRO, the NASA Kennedy Space Center in Florida. After separating from LRO, LCROSS probe has entered a series of orbits around the Earth.
After driving for about 113 days nearly 5.6 million miles (9,000,000 kilometers), LCROSS and the Centaur rocket split over the impact on the moon and reach the ground and explode, LCROSS and LRO spacecraft observed with their instruments board. Were collected about four minutes of data from the first impact with the LCROSS lunar surface.
Killen and his team looked at the impact of the LCROSS Solar Telescope McMath-Pierce at the National Solar Observatory in Tucson, Arizona. They are
were the only team able to see the results of the impact from the ground.
impacts have vaporized material from the crater floor Cabeus, including water and sodium. After the steam plume rose to about 800 meters (about 2,600 meters) high enough to remove the shadow from the edge of the crater, the sun's light has stimulated the sodium atoms, causing them to issue a yellow-orange glow. A high resolution spectrometer, Echelle, attached to the telescope has detected this unique glow. The instrument separates light into its colors and pressed to identify those materials issued by the colors when excited by radiation or by other events in space.
The spectrometer observed the sky through a narrow slit to separate the colors, but the team then had to assume the shape and temperature of the plume and estimated the total amount of sodium released from the impact. Using a computer model and data from other instruments on LRO and LCROSS, the team calculated that have been issued by one to two kilograms (about 2.2 to 4.4 pounds) of sodium.
"This is the 1-2 per cent of the amount of water released from the impacts," said Killen. "Our oceans have a comparable amount of sodium to water ratio, about one per cent" (The amount of ash depends on the temperature derived from observations taken steam).
The presence of these large amounts of sodium raises the question whether it can be reached on the lunar surface by cometary impacts and then trapped in permanently shadowed regions, where it was then frozen.
The solar wind carries small amounts of sodium, which could have become an integral part of the lunar surface and may have been released from lunar rocks, which own about 0.4 percent sodium. Sodium may also have been released from lunar rocks by impacts of meteoroids. (LCROSS impacts do not have enough energy to vaporize the rock, so it is unlikely that the plume of sodium vapor is just came from rocks at the impact site, according to Killen).
"The two percent sodium water is consistent with the amount of sodium in comets, so maybe most of the sodium and water from cometary impacts," said Killen. Although only a 'hypothesis, it is possible that comes from a different source or even from a variety of sources, including lunar volatiles trapped in the cold by chemical processes with the interaction of the solar wind with the surface. "The best evidence for a cometary origin could only be an analysis of isotopes of hydrogen lunar water, concludes Killen.
Isotopes are versions of an element with different weights, o masse. Ad esempio, un atomo di deuterio è una versione più pesante di un atomo di idrogeno comune, perché ha una particella extra, un neutrone, nel suo nucleo centrale. Il deuterio può essere sostituito con l'idrogeno in una molecola d'acqua, ma è molto meno comune e la sua concentrazione varia nel Sistema Solare. Se il deuterio è nello stesso rapporto con l'idrogeno presente nel ghiaccio delle comete, è possibile l'acqua provenga da impatti cometari.
Dal momento che le comete sono come "palle di neve sporca", vorrebbe dire che gran parte del sodio e di altri composti volatili provengono proprio dalle comete.
Il team prevede di far luce sull'origine delle acque lunar and other volatile compounds using the data of the next mission Lunar Atmosphere and Dust Environment Explorer (LADE), which should be launched in May 2013.
The mission will enter into lunar orbit to observe its tenuous atmosphere (exosphere technically called because it is so thin that atoms rarely collide with each other above the surface).
The research was funded by the NASA Dynamic Response Environment (dream) of the Moon project.
The McMath-Pierce telescope is operated by the National Solar Observatory, which is funded by the National Science Foundation and operated by the Association of Universities for Research in Astronomy. The scientific report on this research was published in Geophysical Research Letters in December 2010.
Photo: chamber shows the LCROSS plume emitted about 20 seconds after the impact of the Centaur rocket (Credit: NASA)
Video: Video telling the LCROSS mission with the photographs of the NASA
Video: Video telling the LCROSS mission with the photographs of the NASA
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