Changing Planet

Chasing the Total Solar Eclipse

The Sun's corona radiates in this composite view of the 2009 total solar ecilpse over the Marshall Islands. Courtesy Vojtech Rusin


When the Moon slips between the Earth and Sun this week, Slovak astronomer Vojtech Rusin will be ready on a hotel balcony in Cairns, Australia to witness his 19th total solar eclipse.  StarStruck spoke with the National Geographic grantee, part of an international team, about what it takes to follow the stellar phenomenon.

• You’ve traveled around the world to observe solar eclipses. What’s different or special about this trip?

Total solar eclipses happen regularly around 75 times per 100 years.  This eclipse is very important for studying the finest possible structure of the solar corona—the uppermost layer of the Sun’s atmosphere—which influences the Earth and its magnetic field.

• You’ve seen 18 total solar eclipses. Was any one particularly memorable?

My first one, in Africa, in 1973—it was like my first love.  Everyone remembers their first love!  I traveled through the Sahara from what was then Czechoslovakia to Niger.  The eclipse lasted 6 minutes and 45 seconds, one of the longest durations ever observed.

• How have things changed in the four decades you’ve been studying solar coronas? 

It’s changed so much.  One thing is the imaging techniques have become much more

Total solar eclipse, 1980, India. Courtesy Vojtech Rusin

sophisticated, so we don’t have to take very heavy equipment anymore.  Back in 1980 I traveled by truck from Czechoslovakia to near Bangalore, India; it was something like 10,000 kilometers (6,200 miles).

At each border the customs officers wanted to see documents for every item of the very heavy equipment we were carrying.  We lost a lot of time.  Now we have only a tripod and three telescopes that can be put on one mount, plus a laptop computer.

 • You say this total solar eclipse will last 2 minutes and 3 seconds. How do you calculate so precisely how long the eclipse will last?

Everything is governed by the laws of gravity.  If we know things like the exact positions of bodies, how satellites move around them and the distances between the Earth and Sun, the Earth and the Moon, we can make precise calculations.

• What makes the images you get from each total solar eclipse so different?

The shape of the sun’s corona is constantly changing, this change having a period of approximately 11 years (the solar cycle).  It’s mainly affected by random distributions of magnetic fields on the solar surface entangled by the sun’s rotation. The corona features a plethora of remarkable objects like helmet streamers and polar rays.  There are also coronal mass ejections that create rapid shape change lasting a few hours or so.

 • What’s most exciting for you about watching a total solar eclipse?
You’re always worried about whether the observation procedures will go as planned. It’s euphoric when they succeed.
  • emerson miranda

    I has a lot of significant patterns in it

  • Ima Ryma

    There’s a solar eclipse theory
    That Yang and Wang did theorize –
    A pendulum anomaly.
    Way over my head – no surprise.
    So as a solar eclipse came,
    I dragged out my grandfather’s clock,
    With its pendulum and did aim
    It at the sun. It did tick tock.
    The eclipse – all around went dark.
    What would that pendulum now do?
    For science, I would make my mark.
    Perhaps a Nobel prize – who knew!

    I will report to Yang and Wang.
    My grandfather’s clock stopped dead – dang!

  • Wilhelm Carton

    For the Earth as a whole, the average is 66 total solar eclipses per century, not 75.

  • abu-Abuddy

    I’m always worried about whether the observation procedures will go as planned. It’s euphoric when they succeed.

  • cassano

    natgeo is good for education

  • Jeff Hart

    The eclipse is starting real soon, cant wait! check it out,
    See the eclipse live on webstreaming from
    A Cairns hot air balloon
    A Great Barrier Reef island
    from the beach
    With celestial event experts

  • Michael Spears

    when i was a little boy i seen the moon like this one cross with the sun i thought it was cool so i took a photo and i still have that photo to this day i have been wating to see the earhs feiled

  • pradipdas

    one shouldn’t look after the completion of total solar eclipse !

  • Sujit halder

    Inspirite to me to know about science. Thanks all of you.

  • Vimala Jothi. F

    What a lovely and spectacular view of the Solar Eclipse!.. All thanks to Nat Geo Team….

  • Bill Reyna

    I was with a group that drove to a point about 15 miles west of Port Douglas in order to escape the clouds that were coming in off the ocean. We were very successful and I captured some fine images with a Canon 7D and modified Nikon 1000mm lens. This was total solar eclipse #5 for me.

  • anish patwardhan

    what an awesome pic…and good information too provided..must read…

  • Braydon

    All Lies

  • Yulanda Becci

    Good for homework

  • Yulanda Becci

    Good for homework and a very very very very interesting story

  • Yulanda Becci


  • Chirag Agarwal

    very interesting story…i got a lot of knowledge from it

  • ananda santia

    It must be an interesting job ever…
    Rusin is able to witness such a phenomenal happening
    and the photo is super cool, it looks magical
    It’ll be better if there’s a video of the observation 🙂

  • muhammed ismayil

    Useful as no complexities involved thanks

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