The Sun
Our solar system is made up of the Sun, eight planets, three
dwarf planets and many asteroids, comets and other space rocks.
The Sun is the largest object in the solar system and is located
right at its centre. The planets, dwarf planets, asteroids and
comets travel around the Sun in an ellipse. Our solar system
was formed about 5 billion years ago, and the surface of the
Sun is about 4.6 billion years old.
Quick Q’s:
1. What are sunspots?
Sunspots are storms on
the surface of the Sun.
These storms appear
as huge, dark spots in
satellite pictures and so
are called sunspots.
2. How hot is the Sun?
The Sun’s surface
temperature is about
5,760 °C (10,400 °F),
while its centre is an
incredible 15 million °C
(28 million °F) –
that is more than
150,000 times hotter
than boiling water!
3. How far is the
Sun from us?
The Sun is about
150 million kilometres
(93 million miles)
away from the Earth.
4. What is the corona?
The corona is the
glowing atmosphere
of the Sun that extends
millions of kilometres
into space. The corona
is 200 times hotter
than the Sun’s surface!
5. Is the sun
worshipped by people?
The sun has been
worshipped as a god
since ancient times by
the Greeks, Romans
and native Americans.
Q How was the Sun created?
A Before it was formed, the Sun and the
rest of the solar system was a huge mass of
hot gas and dust called a solar nebula. This
nebula spun faster and faster until the clouds
of gases, dust and ice particles clumped
together and exploded, forming the sun.
Q Why does the Sun glow?
A The Sun is made up of huge amounts of
hydrogen and helium gases. Nuclear reactions
at the centre of the Sun emit a large amount
of energy that makes the Sun glow. That same
energy travels through space and reaches us
as heat and light.
Q What is a solar eclipse?
A A solar eclipse occurs when the Moon
comes between the Sun and the Earth,
blocking the Sun from our view. In a total
solar eclipse, the Moon blocks out the Sun
from our view completely. In a partial eclipse,
however, a part of the Sun is visible. During
an annular eclipse, we can see a small ring of
the Sun glowing around the Moon. When the
Moon is nearer to the Earth it appears larger
and therefore covers the Sun completely,
although it is actually much smaller than the
Sun. However, in an annular eclipse the
Moon is too far away from the Earth to block
the Sun out totally and therefore a ring of
sunlight is seen.
Q What is a solar flare?
A Sometimes the Sun produces a huge
amount of magnetic energy that sends out
jets of gas into space. These jets of gas are
called solar flares and cause a sudden
increase in the brightness of the Sun. Solar
flares are often followed by the release of
electrically charged particles like protons
and electrons. These are called solar winds
and are known to travel at a speed of about
500 kilometres (300 miles) per second.
Flaring up!
Solar flares on the surface of the Sun. Solar flares were
observed for the first time in 1859.
Blocking the Sun
In an annular (ring-shaped) eclipse, the Moon covers
only the middle portion of the Sun, causing a bright ring
of light to appear around the Moon.
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