Core
Several lines of evidence imply that the lunar core is small, with a radius of about 350 km or less. The size of the lunar core is only about 20% the size of the Moon, in contrast to about 50% as is the case for most other terrestrial bodies. The composition of the lunar core is not well constrained, but most believe that it is composed of metallic iron alloyed with a small amount of sulfur and nickel. Analyses of the Moon's time-variable rotation indicate that the core is at least partly molten.
In 2010 reanalysis of the old Apollo seismic data on the deep moonquakes using modern processing methods confirmed that the Moon has an iron rich core with the radius of 330 ± 20 km. The same reanalysis established that the solid inner core made of pure iron has the radius of 240 ± 10 km. The core is surrounded by the partially (10 to 30%) melted layer of the lower mantle with the radius of 480 ± 20 km (thickness ~150 km). These results imply that 40% of the core by volume has solidified. The density of the liquid outer core is about 5 g/cm3 and it can contain as much 6% sulfur by weight. The temperature in the core is probably about 1600–1700 K.
Read more about this topic: Internal Structure Of The Moon
Famous quotes containing the word core:
“In the core of God’s abysm,—
Was a weed of self and schism;
And ever the Daemonic Love
Is the ancestor of wars,
And the parent of remorse.”
—Ralph Waldo Emerson (1803–1882)
“It is possible to have a strong self-love without any self-satisfaction, rather with a self-discontent which is the more intense because one’s own little core of egoistic sensibility is a supreme care.”
—George Eliot [Mary Ann (or Marian)
“Avoiding humiliation is the core of tragedy and comedy.”
—John Guare (b. 1938)