Sunday, June 24, 2007

202)Matter and Energy: two sides of the same coin; how interpreting the light(energy) from the sun gives precise information about the matter in it.

In the very early and very hot Universe, not long after the Big Bang, matter and energy were united in the fabric of the Universe. As the Universe cooled, they then seperated out from each other into particles of matter and particles of the fundamental forces that we find in nature. They are nevertheless two sides of the same coin, as shown by the most famous and well known scientific equation in the world, Albert Einstein's E=MCsquared(Energy equals Mass multiplied by the Speed of Light squared), elucidated in the early part of the 20th century.

The Solar Composition

Although we cannot sample the Sun directly, we can learn a great deal about its composition from the pattern of absorption lines in its spectrum (the Frauenhofer lines). The pattern of these lines serves as a set of fingerprints for the elements that are present in the surface of the Sun, and their intensity serves as a measure of the concentration of these elements.

Solar Elemental Abundances

Element:____ Number %,____ Mass %
Hydrogen: _____92.0, _______73.4
Helium: _______7.8, ________25.0
Carbon: _______0.02, _______0.20
Nitrogen: _____0.008, _______0.09
Oxygen: ______0.06, ________0.8
Neon: ________0.01, ________0.16
Magnesium: ___0.003, _______0.06
Silicon: _______0.004, _______0.09
Sulfur: _______0.002, _______0.05
Iron: ________0.003, _______0.14

The Solar Abundances

Approximately 60 elements have been thus identified in the solar spectrum. The most abundant are listed in the above table, both with respect to the number of atoms or ions present, and with respect to the total mass of the atoms or ions. The Sun is clearly mostly hydrogen and helium, with only a trace of heavier elements. This is also true of the Universe as a whole: most of the Universe is hydrogen, with some helium, and the remainder of the elements occur only in trace concentrations. In that sense the composition of the Earth is highly unrepresentative of the rest of the Universe.

The Discovery of Helium

The element helium is the second most abundant in both the Sun and the Universe, but it is very difficult to find on the Earth. In fact, helium was discovered in the spectrum of the Sun (the name helium derives from helios, which is the Greek name for the Sun). It was postulated that a set of spectral lines observed in the Solar emission spectrum that could not be associated with any known element belonged to a new element (the Sun is too cool to ionize helium appreciably, so absorption lines associated with helium are very weak). Only after this was helium discovered on the Earth and this hypothesis confirmed (helium occurs in certain very deep gas wells on the Earth).


Islam, eminently logical, placing the greatest emphasis on knowledge, purports to understand God's creation:Aga Khan 4(2006)
The God of the Quran is the One whose Ayats(Signs) are the Universe in which we live, move and have our being:Aga Khan 3(1952)
Our interpretation of Islam places enormous value on knowledge. Knowledge is the reflection of faith if it is used properly. Seek out that knowledge and use it properly:Aga Khan 4(2005)