Mercury at the front of the Sun

A rare cosmic event even more rare as a solar eclipse takes place next Monday in the skies over EU. The mercury orbit will begin crossing at the front of the sun at 13:12. The transit of mercury cannot be seen without astronomical tools. It is better to visit an Observatory.

In the calendar by astronomers, the next Monday is marked in bold. Because on May 9, 2016, there is to observe a rare transit of mercury. This pushes the Sun closest planet from the Sun. The cosmic event begins at 13:12. Then, mercury touched the solar disk on the left side.

The mercury is a dwarf compared to the Sun, however. It covers only 0.00012% of the Sun’s surface during the pass. It is not possible therefore without astronomical tools to observe the transit.

Telescope allows observation of the transit of mercury with 50-times magnification

The minimal requirements for the observation of the transit of mercury on Monday is a telescope with 50x magnification. This scope must be mounted on a tripod. It is also important that this telescope is equipped with suitable lens filters, or alternatively has a Sun image projection device.

Mercury at the front of the Sun
Pictures of mercury transit in 2006 from the Sun. Photo: Japan Aerospace Exploration Agency

As a rule of thumb: who can well observe sunspots with a telescope, is prepared for the transit of mercury. For all others: who does not want to miss this event, must visit one of the observatories.

“Elementary particles of the solar wind meet freely on the surface”

For Matthias Mallonn of the Astrophysical Institute Potsdam (AIP) the transit of mercury is more than an exciting cosmic spectacle. The mercury has no atmosphere like our Earth, but about an exosphere, who wants to study Mallonn during a transit.

“The elementary particles of the solar wind meet freely on the surface and lead to chemical reactions” explains Mallonn (AIP AstroPhisics).

Variety of chemical elements are removed, which is soon evaporate into space. “As long as they are still in the vicinity of mercury, they form the exosphere”, says Mallonn. “She is very thin, the concentration of atoms and molecules is about what we call high-vacuum here on Earth.”

Observers should plan plenty of time

However, it apply to plan plenty of time to enjoy this rare cosmic spectacle in full length. After the so-called first contact with the touch of the sun disc by mercury at 13:12:07 pm the second contact comes quickly: at 13:15:10, mercury is completely in front of the solar disk.

Representation of the surface of mercury (coloured), which will push the Monday before the Sun. In fact, the mercury is blacker than asphalt. Graphite makes him appear dark. The surface reflects only 10.6% of the sunlight, while the Moon 12%. Thus, both are darker than asphalt, which throws back 15% of incident sunlight. Photo: Nasa

In the middle of the Sun, the little dot of mercury is located then at 16:55:59. The third contact is reached at 20:37:21, when the mercury starts to leave the solar disk. About three minutes later, at 20:40:33 h, the spectacle is over, the mercury has left the sun disc. These times apply to Berlin as the observation site. For other sites, the deviations can be up to 15 seconds in the German-speaking world.

On Monday, 13 hours of sunshine are expected in Berlin

The weather forecast for the next Monday is pretty cheap, ten hours of sunshine are predicted for many cities, Berlin for example can count with 13 hours of sunshine. Slide then clouds from the Sun, so patience is required.

Because there is only the next chance to watch a full transit of mercury on November 11, 2019, then this opportunity is only on the 13th November 2032 again.