The Sun

Topic 10 – Solar astronomy

10.1 - Understand methods of observing the Sun safely, including:
a - telescopic projection
b - H-alpha filter

10.2 - Know the location and relative temperatures of the Sun’s internal divisions, including:
a - core
b - radiative zone
c - convective zone
d - photosphere

10.3 - Understand the role of the Sun’s internal divisions in terms of energy production and transfer

10.4 - Understand the principal nuclear fusion process in the Sun (the proton-proton cycle)

10.5 - Know the location, temperature and relative density of components of the solar atmosphere, including:
a - chromosphere
b - corona

10.6 - Understand the structure, origin and evolution of sunspots

10.7 - Be able to use sunspot data to determine the mean solar rotation period

10.8 - Be able to use sunspot data relating to the solar cycle

10.9 - Understand the different appearance of the Sun when observed using radiation from the different regions of the electromagnetic spectrum

Topic 3 – The Earth-Moon-Sun system

3.8 - Understand the appearance of the Sun during partial, total and annular solar eclipses, including the terms first, second, third and fourth umbral contact

3.9 - Understand the appearance of the Moon during partial and total lunar eclipses, including the terms first, second, third and fourth umbral contact

3.10 - Understand the causes of solar and lunar eclipses

Topic 5 – Solar System observation

5.1 - Understand how to use pinhole projection to observe the Sun safely


The Sun is the largest body in the Solar System, containing over 98% of the total mass of the entire system and mostly consists of hydrogen and helium. The gravitational pull of the Sun is what keeps everything in the solar system in orbit around it.

Find out how to observe the Sun safety, how hot it is, how fast it rotates and what makes it hot.

At the end of this section take the mini quiz to test yourself.


WARNING: Never view the Sun with a telescope or binoculars


Did you know?

The Sun is a star in our galaxy, the Milky Way. It takes 225 million Earth years for the Sun to revolve around the galaxy.

Did you also know?

The Sun is classed as an ordinary G2 medium sized yellow dwarf star.


Nine Planets Sun Information