About the Eclipse

What is a Solar Eclipse?

A solar eclipse occurs when the Moon passes between the Earth and the Sun, blocking all or part of the Sun's light. There are three types of solar eclipses:

Total Solar Eclipse: The Moon completely covers the Sun, and it gets dark as if it were night for a short period.  This is the most spectacular eclipse and is the type we will experience in 2028.

Partial Solar Eclipse: Only part of the Sun is obscured by the Moon.

Annular Solar Eclipse: The Moon covers the centre of the Sun, leaving a ring-like appearance of the Sun's outer edges, often called a "ring of fire."

Solar eclipses can only happen during a new moon, when the Sun and Moon are in line as seen from Earth.  As Earth rotates, the Moon's shadow on Earth – and the view of the eclipse – travels from west to east.

How often does a solar eclipse occur?

There are two to five solar eclipses each year, with a total eclipse taking place every 18 months or so.  Whether you can view that eclipse depends on where you are in the world.  And as 70% of our planet is ocean, most eclipses cannot be seen from land.  Also, because the Moon’s shadow is only about 150 km wide on average, the chance of an eclipse in a specific location is much less.  A total solar eclipse occurs in the same place on the planet once every 366 years on average.

However, calculations show that the last total solar eclipse seen from any location in the South Island of New Zealand was in the year 1163 – before human settlement.  The next eclipse for Dunedin won’t be until 2068.   So, the solar eclipse on 22 July 2028 really is a rare event!

Scientific Significance

Studying solar eclipses is important because it helps scientists understand various aspects of the Sun, the Moon, and Earth's atmosphere. Here are a few key reasons:

Solar Corona Observation:  During a total solar eclipse, the Sun's outer atmosphere (the corona) becomes visible.  This allows scientists to study its structure and behaviour, which is usually hidden by the Sun's bright light.

Solar Physics:  Eclipses provide a unique opportunity to study solar flares, prominences, and other solar phenomena, improving our understanding of the Sun's activity and its effects on space weather.

Testing General Relativity:  Eclipses have been used to test Einstein's theory of general relativity by observing the bending of light from stars passing close to the Sun.

Atmospheric Studies:  Eclipses affect Earth's atmosphere, offering insights into atmospheric conditions and changes.

Human behaviour:  Emerging studies into psychological changes from the experience of observing a total solar eclipse.

Historical Data:  Historical records of solar eclipses help astronomers understand changes in Earth's rotation and orbital dynamics over long periods.

Overall, solar eclipses serve as natural laboratories for advancing our knowledge of both our star and our planet.