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Watch the sun disappear with AU

AU will be taking a front row seat on 20 March, when Denmark will have a chance to watch the sun disappear behind the moon’s shadow, one of the most spectacular phenomena in astronomy: a solar eclipse.

20 March 2015 is your chance to experience a natural phenomenon that has fascinated people throughout history: a solar eclipse right here in Denmark. Like star-crossed lovers, the sun and the moon become one in an enchanted moment. A solar eclipse is an unforgettable scene in nature’s great drama. For a few minutes, day becomes night. Animals instinctively believe it’s time to go to sleep for the night. Incurable romantics propose, champagne corks fly, and myths and mysteries are born. Everything familiar is made strange. To experience an eclipse is to witness definitive proof that the world is a very tiny part of an unimaginably large solar system.

This fascination with solar eclipses we all feel is particularly strong in astrophysicists. Like the leading astrophysicists at Aarhus University’s Stellar Astrophysics Centre (SAC), who are investigating our own star, the sun, and stars far out in the universe. Over the past three years, researchers at SAC have contributed to identifying several thousand new solar systems and mapping the interior of stars.

Ole J. Knudsen, a researcher at SAC, is one of Denmark’s best-known speakers and communicators when it comes to bringing astrophysics to the general public.

“A solar eclipse is a dramatic astronomical phenomenon. I think it fascinates so many people because it reminds us that we’re part of something much larger.”

Solar eclipses can either be total or partial. The eclipse on 20 March with only be total on Svalbard in northern Norway and on the Faroe Islands. Which means that tickets on the cruise ships and planes to these areas sold out long ago. Knudsen himself made sure to book his ticket in good time.

“During a total solar eclipse, you get to experience what’s called the corona - just at the moment when the moon shadows the sun completely. At this moment, the corona is like a ring of flame around the moon with a completely unreal and indescribable pearly light. No photo can capture it. It has to be experienced,” he explains.

In Denmark, the eclipse will be partial, and we will be able to see the moon covering 80 to 85 per cent of the sun’s surface. The last time we experienced a similar eclipse in Denmark was in 1999 - in fact, we have to go 50 years back in time to find a partial eclipse of the same depth. And we won’t have another chance for many years.

Watch the show - but remember your safety glasses

“I hope that a lot of people will take advantage of this chance to have a truly extraordinary nature experience. And it’s a good idea to prepare carefully. This is an excellent opportunity to learn about the solar system, after all. There are also some safety precautions you need to take. Looking directly at the sun can damage your eyes,” explains Knudsen.

However, there are some persistent myths about this. In particularly, many people believe that the sun is particularly dangerous during an eclipse. In fact, during the 1999 eclipse in Denmark, there were numerous examples of parents who demanded that their children be kept indoors at school during the eclipse. This is unfortunate in Knudsen’s view, and he encourages people not to cheat themselves or their children of the experience of watching a solar eclipse. There is no risk involved in watching an eclipse as long as you protect your eyes with approved solar glasses or filters.

Learn more about how to protect your eyes during a solar eclipse

“The sun is always dangerous for the eyes - it hurts to look directly at the sun, which is why you should never do it - and that includes during a solar eclipse. And without filters, you wouldn’t be able to see anything in any case. But it’ll be a shame if fear makes people to stay indoors. Under safe conditions, it can be an experience that you’ll remember for the rest of your life,” says Knudsen.

Eclipses of the imagination

Throughout the ages, solar eclipses have been shrouded in mystery and fascination. They have always sparked our imaginations.

The Vikings believed that solar eclipses were caused by the wolf Skoll chasing the sun across the sky. Solar eclipses happen when the wolf manages to take a bite out of the sun. And at the end of the world - Ragnarok - the Vikings believed that Skoll would swallow the sun whole.

Famous writers have also used solar eclipses in their work. For example, in Prisoners of the Sun, Hervé used a solar eclipse to save Tintin and Captain Haddock from being burned alive by the Incas with Professor Tournesol. The terrified Incas set the three heroes free because they believe that Tintin has commanded their sun god to bring about the eclipse.

"In ancient and modern times, there are innumerable examples of historical traces of how solar eclipses have fascinated ordinary people and scientists. For example, the figures on the famous Golden Horns of Gallehus have been interpreted as a description of a solar eclipse. The same is true of the Nebra sky disk, one of the most fantastic archaeological finds from the Bronze Age, ” Knudsen explains.

However, solar eclipses are no longer the object of intense scientific interest. At one time, scientists flocked to solar eclipses because this was the only opportunity to study the sun’s corona. Today, telescopes enable scientists to study the sun’s atmosphere at any time. Nonetheless, the sight of the sun being slowly devoured by the moon will always be a unique experience.

Solar eclipses in Denmark

  • The solar eclipse on 20 March 2015 will be partial here in Denmark and total in a belt stretching across the North Atlantic and up to the North Pole. The total eclipse will be visible from the Faroe Islands and Svalbard in northern Norway.
  • In Denmark, the eclipse will start at 9.40 CET and end at 11.58. The climax of the eclipse will occur at 10.48. At this point, 83.45 per cent of the sun’s surface will be obscured as seen from Aarhus. Further south-east, the percentage will be slightly lower (min. 81 per cent), and further north-west slightly higher (max. 85 per cent).
  • The next partial eclipse in Denmark will take place on 10 June 2021. But only 25 per cent of the sun’s surface will be obscured.
  • The next total solar eclipse visible in Denmark will take place on 25 May 2142 at 10.04 CET.
  • The most recent total eclipse took place on 28 June 1851, when the sun was completely obscured in Northern Jutland and Northern Zealand.
  • There have been a number of partial solar eclipses in Denmark in recent years. The deepest of these took place on 15 February 1961, 11 August 1999 and 31 May 2003. The 1999 eclipse covered about 80 per cent of the sun as seen from Denmark.

Source: Stellar Astrophysics Centre (SAC), Aarhus University

What is a solar eclipse?

  • A solar eclipse is what you see when the moon passes between the sun and the earth, and the moon fully or partially blocks the sun’s disk.
  • Eclipses can be total or partial.
  • During a total solar eclipse, the moon obscures the entire surface of the sun’s disk. A total eclipse typically lasts between two and five minutes.
  • During a partial solar eclipse, the sun is reduced to a smiley. You will also notice that shadows change: for example, if you look at the spots of light on the ground that are made by the sun shining through the leaves of a tree, you will notice that they’re crescent-shaped, and not round as they normally would be. You can see this particularly clearly on a sidewalk.
  • Solar eclipses occur quite regularly: approximately twice a year, most often as a partial eclipse.
  • At any given location on earth, a total eclipse will occur approximately once every 370 years.