This YouTube from Australia is fun watch. This is a replay of the total solar eclipse, as ANU professor of astronomy Dr Charley Lineweaver joins ABC News Breakfast to explain what is going on
"This eclipse occurs near the peak of what is known as Cycle 24, when coronal activity, mass ejections, solar flares are expected to be more energetic," Dr Soria says.
This cycle is the weakest it has been in more than 100 years. The current cycle follows a series of three strong solar cycles that occurred between 1980 and 2000.
"Weaker cycles generally lead to a cooling climate - as was the case in the 1810s and 1880s, with similarly weak cycles – and vice versa," Dr Soria says.
If scientists get a better understanding of temperature, structure and energy processes in the solar corona and the solar wind, they can then make better predictions about the long-term solar variability and the effect it has on the Earth's climate and magnetic field.
For one thing, it would help to make solar flares - the mightiest of explosions in the whole solar system - more predictable.
A solar flare occurs when energy from the core moves slowly outwards, sometimes leaping forth in the lower gaseous layer of the sun's atmosphere - the pinkish-red region known as the chromosphere or colour-sphere. It belches out in an immense jet of fiery flame, sometimes extending tens of thousands of kilometres into space.
Big flares cause power blackouts on Earth. They also affect communications satellites. The sun has an 11-year cycle, with huge flares occurring during peak activity, which we are approaching now. The peak is expected by the end of next year.
Call back the past
Before the dawn of the space age, a solar eclipse was the only way that scientists could study the solar corona.
"It was common for observatories around the world to mount large expeditions to remote parts of the world, carting heavy equipment to record the fleeting details of the corona in the few minutes of totality offered by an eclipse," says John Kennewell, director of the Australian Space Academy.
When it became possible to launch into space solar telescopes that could create artificial eclipses using an instrument called a coronagraph, the need for ground-based eclipse observations decreased.
"The reason for the continuing interest in ground-based eclipse observations was that the images from space, even up until the late 1980s were not all that good," Dr Kennewell explains.
The situation changed with the launch of the solar and heliospheric observatory (SOHO) in 1995. This spacecraft carried a coronagraph called LASCO (Large Scale Coronagraph), which has provided high-resolution images and scientific data on the solar corona.
"Not only has it answered many question about the sun's atmosphere, it revolutionised our knowledge of coronal mass ejections, which are clouds of plasma containing around 5 billion tons of matter that are flung from the sun and which can cause magnetic storms on the Earth," Dr Kennewell says.
Some scientists still study eclipses for the atmospheric effects observed, while some biologists monitor the behaviour of animals during eclipses.
"So while it is true that space based instruments have significantly reduced the interest in total solar eclipses, it has not totally disappeared, and with significantly reduced funding for replacement space observations, it may well be that future interest in ground-based eclipse studies will increase," Dr Kennewell says.
"Apart from the scientific interest, a total solar eclipse is an awe-inspiring event. Everyone should aspire to observe at least one such eclipse in their lifetime."
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