On Wednesday, August 12, 2026, residents are in for an extraordinary astronomical day, from a morning alignment of six planets, through a partial solar eclipse at sunset, to historically favorable conditions for observing the Perseid meteor shower.
A rare confluence of astronomical events will unfold on Wednesday, August 12, 2026, when, in just 24 hours, the sky above Croatia will stage a triple spectacle. The Adriatic Aerospace Association (A3) has announced that citizens will be able to witness a morning planetary alignment, a partial solar eclipse in the late afternoon, and ideal conditions for observing the Perseids during the night.
The celestial show begins in the early morning hours, just before sunrise. As many as six planets will align along the ecliptic. Saturn will be high in the sky, Mars will stand out with its reddish hue, while Mercury and Jupiter will be visible very low on the eastern horizon. Spotting Uranus and Neptune will require binoculars or a small telescope. For the best experience, viewing should start 30 to 60 minutes before sunrise at your local location.
In the late afternoon, a partial solar eclipse will be visible over Croatia. Its position low on the western horizon creates a rare astrophotographic effect known as a "setting eclipse." A3 has issued a stern warning about safety measures. "We strongly warn that the Sun must never be observed with the naked eye, through sunglasses, smoked glass, or uncertified optical equipment, even when it is low on the horizon and appears less dazzling due to the thicker atmosphere," the association stated. They emphasize that observation is safe only with specialized ISO 12312-2 certified filters, such as Mylar sheets or welding glass with a shade of DIN 14, or by using the projection method. Failure to follow these guidelines can result in permanent and irreversible eye damage.
In Zagreb, the Moon will begin to cross the Sun's disk at 7:25 PM. The maximum eclipse is expected at 8:06 PM, with a magnitude of 0.765. Viewing time will be short, as the Sun sets in Zagreb as early as 8:09 PM, so the final moments of the eclipse will practically coincide with sunset. "The eclipse in Croatia begins around 7:25-7:30 PM, but the Sun sets in Croatia, depending on which city you are in, between 7:53 and 8:17 PM. We won't see the maximum eclipse; instead, the Sun will set below the horizon," explained Dr. Darije Maričić, director of the Zagreb Observatory.
While northern and western parts of Europe will witness a total eclipse, Croatia will see only the partial phase. The Moon's shadow travels across the Earth at an average speed of 1 kilometer per second, and its width ranges from 150 to 270 kilometers, depending on the Moon's distance from Earth. This time, the path of totality includes Greenland, Iceland, and Spain. "The diameter of the Sun that the Moon will cover is between about 50 and 90 percent. Western parts of Croatia will see slightly higher values, while eastern and southern parts will see slightly lower values," Maričić added.
The observatory director also clarified that eclipses are not an extremely rare phenomenon. "In general, two are visible from Earth in 75% of calendar years, and in some years, three to four eclipses can be seen, which are rarer. There are even years, like 1935, when there were five passages of the Moon in front of the Sun." However, for a total solar eclipse visible from Croatia, we will have to wait until September 3, 2081, while the next partial eclipse will be visible as soon as August 2, 2027.
The Zagreb Observatory has prepared a special program for the public. Before the eclipse begins, there will be a public lecture on solar eclipses and how to observe them safely, and participants will have the opportunity to view it through several solar telescopes equipped with special protective filters. In addition, the observatory will also broadcast live the total solar eclipse from Spain.
The culmination of the astronomical day will occur on the night of August 12-13, when the Perseid meteor shower reaches its peak. What makes this year's maximum historically significant is that it perfectly coincides with the new moon. With no moonlight, the sky will be completely dark, significantly increasing the chances of seeing impressive fireballs. Due to the way the planets move, such ideal conditions will not repeat for the next ten years.
The zenithal hourly rate is expected to be between 80 and 100 meteors per hour. The most intense activity is predicted for the second half of the night, from after midnight until the early morning hours. For the best experience, it is recommended to go out into nature, away from city lights, and allow your eyes to adapt to the darkness for at least 20 to 30 minutes.
The Adriatic Aerospace Association has issued a public call to all cities and municipalities to turn off or reduce the intensity of public lighting, especially decorative lighting on public buildings and monuments, on the night of August 12-13, in line with safety considerations. "Besides allowing citizens to observe this historic celestial spectacle without hindrance and safely, this event is crucial for raising public awareness about the growing global problem of light pollution," A3 stated.
They also reminded local self-government units of their legal obligation under the Law on Protection against Light Pollution, which mandates the ecological optimization of public lighting systems. "Reducing light pollution is not just an astronomical interest; it is essential for preserving the nocturnal environment, biodiversity, and protecting human health and the natural circadian rhythm," the appeal reads.
