Sodium tail of the Moon
Encyclopedia
The Moon
has been shown to have a "tail" of sodium
ion
s too faint to be detected by the human eye
. It is hundreds of thousands of miles long, and was discovered in 1998 as a result of Boston University
scientists observing the Leonid
meteor storm. The Moon is constantly releasing atomic sodium gas from its surface, and solar
radiation pressure accelerates the sodium atoms in the anti-sunward direction, forming an elongated tail which points away from the Sun. The 1998 Leonid meteor shower temporarily tripled the mass of the tail by adding to population of sodium atoms being outgassed by the Moon.
The daily impact of small meteors
and the like produces a constant "tail" on the Moon, but the Leonids had intensified it, thus making it more observable from Earth
than normal.
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
has been shown to have a "tail" of sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
ion
Ion
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
s too faint to be detected by the human eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
. It is hundreds of thousands of miles long, and was discovered in 1998 as a result of Boston University
Boston University
Boston University is a private research university located in Boston, Massachusetts. With more than 4,000 faculty members and more than 31,000 students, Boston University is one of the largest private universities in the United States and one of Boston's largest employers...
scientists observing the Leonid
Leonids
The Leonids is a prolific meteor shower associated with the comet Tempel-Tuttle. The Leonids get their name from the location of their radiant in the constellation Leo: the meteors appear to radiate from that point in the sky. They tend to peak in November.Earth moves through the meteoroid...
meteor storm. The Moon is constantly releasing atomic sodium gas from its surface, and solar
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
radiation pressure accelerates the sodium atoms in the anti-sunward direction, forming an elongated tail which points away from the Sun. The 1998 Leonid meteor shower temporarily tripled the mass of the tail by adding to population of sodium atoms being outgassed by the Moon.
The daily impact of small meteors
Meteoroid
A meteoroid is a sand- to boulder-sized particle of debris in the Solar System. The visible path of a meteoroid that enters Earth's atmosphere is called a meteor, or colloquially a shooting star or falling star. If a meteoroid reaches the ground and survives impact, then it is called a meteorite...
and the like produces a constant "tail" on the Moon, but the Leonids had intensified it, thus making it more observable from Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
than normal.