Join IPA Slovenia to watch the transit of Mercury!

20 Jul 2019

Astronomy enthusiasts invited to observe rare astronomical phenomenon in Slovenia

A transit of Mercury across the Sun is an extraordinary space phenomenon that one can observe only with the use of a proper telescope. Members of IPA Club Štajerskavas are therefore welcoming you to join them in Ptuj on 11th of November 2019. The event will be led by IPA Club member Marko Vidovič, whom we talked with in the middle of the preparations for this day, which is significant for astronomy enthusiasts.marko

 What kind of space phenomenon are we talking about? What makes it special?

A transit of Mercury across the surface of the Sun is quite an uncommon space phenomenon. The last one was in May 2016, which we also observed at Castle Ptuj. Essentially, each eclipse is exceptional in a way, whether it is an eclipse of the Sun, the Moon, Venus or Mercury, since they do not occur often.

Where can we get the best view? What about at home? Or elsewhere in Europe?

The transit of Mercury can be seen anywhere in Europe; however, the best view will be at high altitude, because at that time the Sun is low in the south. Therefore, we need to choose a location that is high in altitude and enables the view of the Sun until sunset. In our region, we will only be able to observe the beginning of the transit, which will happen at 1.35 pm, and until the middle of the phenomenon at 4.19 pm, while the Sun goes down already at 4.22 pm.

How can we safely observe this space phenomenon?

Each look towards the Sun without proper filters can cause blindness, especially if one uses a telescope or binoculars. Unfortunately, this event cannot be viewed with a naked eye or with the use of binoculars, because Mercury is simply too small when crossing the Sun. The transit can hence be followed only with a telescope that is capable of great magnification and with the use of a proper filter for safe observations, of course.

In case we miss it, when is the next opportunity to observe this phenomenon?

If we miss this event, or if the weather will not be favourable to us, the next transition of Mercury will happen on 13 November 2032, however the next transition of Venus will take place very far from now, in 2117.

Which similar space phenomenon will follow this one?

The next interesting space phenomenon will occur on 28 of November 2019, at 9.31 am, when the Moon will cover Jupiter.

The event will be led by Marko Vidovic between 3 – 5 pm at Castle Ptuj. The passage of Mercury can be seen only with suitable telescope with appropriate settings. The next chance to see this phenomenon will be in 2032. If you’re going to watch it yourself, proper safety is needed! Since the Sun is by far the brightest body in the sky, use ‘mylar’ foil, suitable sun filters, glasses or welding glasses. More information about the event and accommodation:

Albin Gradišnik (

Anita Kovačič, IPA Slovenia