CH. 29.1 – THE SUN Chapter 29 – March 13 th, 2015

CH. 29.1 – THE SUNChapter 29 – March 13th, 2015

VOCABULARY TO KNOW…

Photosphere – Chromosphere – Corona – Convection Zone – Radiative Zone – Nuclear Fusion -

CONTENTS OF THE SUN

The sun is made up of…75% Hydrogen 24% Helium 1% Other Gases

It is powered by FUSION = where lighter nuclei is combine to make heavier ones

Thus, releasing LOTS of ENERGY!

** EACH STEP RELEASES ENERGY **

#1. 2 hydrogens ( protons) fuse, the second p+ is neutralized by emitting a positron…so that proton becomes a neutron (p+ no pair created)

2. Another H proton combines with the first p+no pair…creates a helium isotope (2 p+, 1 no)

3. These helium isotopes, each with 2p+ 1no, fuse and release two protons leaving behind a “common” helium atom.

** EACH STEP RELEASES ENERGY **

ABOUT ENERGY…

Neutrinos (uncharged “electrons”… 1/10,000 the size of an e-) are also released and reach Earth in 8 minutes

Helium (He) product is 0.7% less massive than the Hydrogen (H) that formed it….

--that MASS is converted into ENERGYTHIS energy causes intense shine and heat.

MASS -> ENERGY

1905:Nucleus of atom/fusion unknown…Einstein proposed: small mass yields large energy

This is known as the Theory of RelativityE=mc2

Scientists used E=mc2 to explain the sun’s huge quantities of E.

E = mc²E = energy M = mass of matter changedC = speed of light

SUN’S STRUCTURE

1. Core gaseous25% of sun’s diametertemp 15,000,000 oC)

Super dense (10x that of ironheat & pressure cause atoms to separate into nuclei and e-s. (remember, nuclei are +)

Nuclei try to repel but heat/pressure force them to fuse.

2. Radiative - Outside core 2-7,000,000oC E moving as EM waves3. Convection (30% of Sun) 2,000,000 oC E moving as convection (hot gases move out,

expand, lose E…become dense and sink back down in convective zone…repeats)

Corona is seen during solar eclipses

ATMOSPHERE OF THE SUN…

4. Photosphere gases risen out of convective (6,000oC)

5. Chromosphere color sphere 6-50,000oC g as shoots up from photosphere

6. CoronaTemps. spikes here (above 1,000,000 oC) ions can escape---this is solar wind.