A brief historical overview
Among the Romans, who laid the foundations of our calendar, the era began with the foundation of Rome, fixed in 753 BC (Ab Urbe condita or AUC). However, there were other starting dates. Since the 3rd century AD, the years have been calculated from the ascent of the Emperor Diocletian. Since he persecuted Christians, this time was called the era of the martyrs. In the 6th century, the monk Dionysius Exiguus (Dionysius the Little) began to count from the year that, according to him, was the year of Christ's birth. Thus, 248 Anno Diocletiani was in fact the year 532 AD. According to Dionysius, Jesus Christ was born on December 25 of the year before year 1, he did not know the number zero, but there is no era in which a year 0 would be placed. In the 8th century, the English Father Bede the Venerable also began to count the years before Christ. The year 1 BC was therefore just before the year 1 AD. The year 1 BC was therefore the last year of the 1st century BC. It should be noted that this Christian way of counting years was used by the Church in the Middle Ages and much later in the civil world. There were many other ways to count. There were controversies about the date of the beginning and in particular about the year of Christ's birth and Herod's death in 4 BC, which should be brought forward by a few years, to around 6 or 7 BC. You can find more information about calendars on The Calender FAQ web page.- spring begins on March 20 at 22:58 (universal time);
- the first full moon that follows takes place on March 21 at 2:43 (universal time).
- spring begins on March 21;
- the first full moon after March 21, 2019 (according to Meton calculations) takes place on April 20, 2019.
- The Sun is not perceived from the Earth as a point but as a luminous disc. Sunrise (sunset) is defined as the time when the upper edge of the solar disc, not the centre of the Sun, appears (disappears) on the horizon. Therefore, since the upper edge of the Sun appears before its centre, and disappears after its centre, we gain a few minutes of sunlight during the equinox.
- Sunlight is deflected by the atmosphere. This is due to atmospheric refraction, a phenomena that “flattens” the Sun near the horizon. As a result, the upper edge of the Sun may be visible when it is actually below the horizon.

A meteorite is a piece of rock from space that enters the atmosphere. It does not burn up (like a meteor) and reaches the surface of the Earth. It is quite rare to find a meteorite, especially in an urban environment.
There are different kinds of meteorites, but there are some general characteristics that can help to decide if the rock is a meteorite.
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Meteorites are magnetic: they won’t stick on a fridge themselves, but a magnet will stick to the meteorite.
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The rock seems burned on the outside. A meteorite has a rounded shape and brown rusty, to black color because of the heat during atmospheric entry.
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You will not see holes or pores at the surface of a meteorite. Sometimes you can see shiny or rusty patches of iron.
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A meteorite will feel heavier compared to a rock from earth of the same size.
The Royal Observatory of Belgium does not identify or collect meteorites. If you think you found a meteorite, you can use the document below to verify. Still convinced it is a meteorite? Contact mdeceukelaire@naturalsciences.be from the Royal Belgian Institute for Natural Sciences. Add some pictures (with scale) and a description (location, exterior, weight, volume, magnetism, …) from the rock. This will make identification easier.
Meteorite or meteowrong?