Partial eclipse of the sun
This Tuesday, January 4, the sun has an important rendez-vous with the moon! The solar eclipse will be most impressive at 09:10 Lausanne time, and the Callista association is organizing an observation event on the EPFL campus.
Eclipses of the sun are rare. The next total eclipse visible from Switzerland will occur on September 3 . . . 2081! In the meantime, we will have to be content with less spectacular phenomena, though still interesting to observe: partial solar eclipses. And that’s exactly what the celestial movements will be unveiling on the morning of January 4. Around 09:10, the moon will cover the sun to a level of 70%.
From a practical perspective, although the eclipse is only partial, it’s essential to use safe viewing accessories to observe it. The familiar eclipse spectacles, that filter 99.999% of the light, will be available from the Callista association, which is organizing a public observation event at the Place Cosandey (to the west of the Rolex Learning Center). The event will end at around 10:30.
“Scientifically, the eclipses of the 21st century are not particularly interesting”, explains Malte Tewes of EPFL’s Laboratory of Astrophysics. “Whereas in 1919 the eclipse of May 29 enabled the confirmation of Einstein’s relativity theory. During total eclipses of the sun, it’s possible to see the stars in the sky, and the British astrophysicist Arthur Eddington used this event to measure their exact position in the heavens. In doing so, he realized that their light is deviated by the mass of the sun. Einstein was right!”
Today, satellites can emulate solar eclipses by positioning small masks in the optical paths of their telescopes. This technique enables the continued observation of the sun’s outline, and helps us to understand how its corona functions. Scientifically, there won’t be much to learn from the eclipse of January 4, but the event is still worth following.
Link:
http://memento.epfl.ch/cgi-bin/memento/view?manif=19599