Partial solar eclipse over Germany

On March 20th a cosmic game of shadows will take place in the skies over Central Europe: in the late morning, the new moon will slide over the sun and obscure it by up to 80 per cent. Daylight will become noticeably more pale. In Germany, the next partial eclipse of this scale will not take place for another eleven years. What causes this natural phenomenon? And what are the safest ways to view it?

This coming Friday the sky will darken. At around 9:30 AM, the new moon will come into contact with the eastern rim of the sun’s disk. And thus begins a game of shadows, the likes of which we will not be seeing again in our corner of the world until 12 August 2026. This time we will not be treated to a total eclipse, but as the partial phase culminates, the moon will still cover up to 80 per cent of the sun.

General rule of thumb: the further north you are, the greater the degree of totality. While this equates to just about 68 per cent in Munich, observers elsewhere in the country will witness the sun being obscured by a good 75 per cent in Berlin, 79 in Hamburg and more than 80 per cent in Kiel. Even the time of day at which the eclipse is visible fluctuates: here in Germany, the partial eclipse will begin between 9:26 AM (Freiburg in the far south of the country) and 9:41 AM (Stralsund in the far north). The maximum will be reached in both of these locations between 10:34 and 10:49 AM, and the spectacle will end between 11:46 AM and 12 noon respectively.

The sun will already be high in the sky by the time the eclipse occurs. Even if the skies are clouded over, daylight will become dimmer as the eclipse reaches its maximum. Clear skies are ideal for viewing the cosmic spectacle. You can even see it with the naked eye – but only with the right protection! Staring into the extremely bright disk of the sun without taking the necessary precautions can cause irreversible eye damage. Special “eclipse glasses” can be purchased over the Internet or from specialist retailers. If you already own a pair of eclipse glasses, inspect them to make sure that they are not damaged, scratched or punctured.

When viewing the eclipse without an optical instrument, you will see how the pitch-black disk of the new moon gradually “eats away” at the sun. If you use a telescope with suitable magnification, you will notice that the edge of the moon is not completely smooth: here and there, the lunar landscape is revealed in the form of tiny jagged edges or indentations.

It is also possible that the moon occasionally covers one or more sunspots as it travels across our daystar. When contrasted with the inner zone of a sunspot (umbra) and especially with the brighter aureole (penumbra) surrounding the latter, the moon appears even blacker.

If you wish to view the eclipse using an optical instrument, make sure you only use materials that have been approved by the manufacturer. The best option is to use foils or filters that prevent light from entering the instrument in the first place; accessories known as ocular filters, on the other hand, might crack due to the intense heat and are therefore not advisable. The safest viewing method is to project the image of the sun onto a white screen, where it can be viewed without any risk by many people at once.

On March 20th the sun, the new moon and Earth will all be aligned. Due to the fact that the moon’s orbit is tilted at five degrees to the plane on which Earth orbits the sun, this type of constellation is relatively rare. Only when the moon is located close to one of the two “nodes” (the points at which the two orbits intersect) does its shadow reach our planet.

At 10:14 AM on March 20th, the tip of the umbral cone will touch down on Earth’s surface in the North Atlantic, south of Greenland. That is where a total solar eclipse will now begin. The umbral shadow then races across the open sea in a north-easterly direction at several times the speed of sound. Its path leads between the British Isles and Iceland and across the Faeroe Islands towards Spitsbergen before ending in the Artic, just 70 kilometres shy of the North Pole. The eclipse’s totality will last a maximum of 2 minutes and 47 seconds.

Due to the fact that the umbra’s trajectory mostly passes across open waters or uninhabited areas, only a small number of people will be able to view the total phase. The Slooh Community Observatory on the Faeroe Islands plans to broadcast the eclipse over the Internet via live streaming. The European Space Agency (ESA) will also be following the spectacle closely: the mini-satellite Proba‑2, which orbits Earth from 820 kilometres away, will observe the sun, while other satellites from the Proba family will track the moon’s shadow as it travels across Earth’s surface.

Contact

Helmut Hornung
Administrative Headquarters of the Max Planck Society, München
Phone: +49 89 2108-1404

Email: hornung@gv.mpg