Transcript g9u4c11

Chapter 11
The Sun
average-sized star.
 300 000 times more mass than Earth
 The sun’s mass results in great
pressure and heat at the centre of the
Sun cause a thermonuclear reaction
 Hydrogen is converted to helium
 it has enough hydrogen to last another 5
billion years.

The Sun
contains more than 99 percent of all the
mass in the solar system
 The tremendous radiated energy that is
produced keeps Earth warm enough to
support life

The Sun
Sunspots dark patches on the Sun’s
surface that are slightly cooler, about
3500°C, than surrounding areas
 Occasionally, extremely violent eruptions of
gas called solar flares also occur. These
eruptions can last for a few hours and heat
gases to 11 000 000°C.

The Sun
Sun spots and solar flares are
associated with Solar wind .
 Exposure to solar wind could be fatal for
any organism living on Earth.
 Earth’s magnetic field deflects most of
the solar wind around the planet

The Sun

Some of the high-energy particles in solar
wind enter Earth’s atmosphere at the North
and South Poles, where they collide with
gases in the atmosphere.
aurora borealis and aurora australis
Northern and Southern Lights
The Sun
Questions
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