Two eclipses will be visible from Earth this August: a total solar eclipse on 12 August, seen from the Northern Hemisphere, and a partial lunar eclipse on the night of 27 into 28 August, which will be visible from Brazil.
According to Brazil's National Observatory (Observatório Nacional, ON/MCTI), the total solar eclipse on 12 August will not be visible from any part of Brazil, not even partially.
The absence of the eclipse from Brazilian skies comes down to geometry. The Moon's shadow will fall on the Northern Hemisphere, covering a band that passes through parts of Russia, Greenland, Iceland, Spain and Portugal.
Partial lunar eclipse over Brazil
On the night of 27 into 28 August, a partial lunar eclipse will take place. In Brazil, the event begins at 10pm. According to Dr Josina do Nascimento, an astronomer at the National Observatory, 96.2% of the Moon will be obscured during the event.
Nascimento explained that the position of the observer determines what is seen in the sky. Solar eclipses happen when the Moon passes between the Sun and the Earth, casting its shadow on the planet, she said. The darkest part of that shadow, where sunlight is completely blocked, is called the umbra, and it is surrounded by a lighter shadow, the penumbra, where sunlight is only partially blocked.
An observer standing in the narrow band of Earth struck by the umbra sees a total eclipse, while someone in the area reached by the penumbra sees it as partial, Nascimento said. She added that the same geometry applies to an annular eclipse, except that in that case the Moon's apparent diameter, meaning how large it looks in the sky, is smaller than the Sun's apparent diameter. As a result, the Sun is not fully covered, day does not turn to night, and stars do not appear, but the Sun darkens and takes on a bright ring-like outline. Nascimento said the longest a total solar eclipse can possibly last is 7 minutes and 30 seconds.
When are the next solar eclipses?
Total or annular solar eclipses occur on Earth about once a year on average, but each one covers only a very narrow strip of the planet, which is why they can feel like rare events.
An annular solar eclipse on 6 February 2027 will have its band of visibility over the sea, grazing the coastline of the far eastern part of Rio de Janeiro state. That eclipse will be seen as partial across nearly all of Brazil, except in the extreme northwest.
The next total solar eclipse in the world will take place on 2 August 2027, crossing southern Spain, northern Africa and Saudi Arabia. It is already drawing attention for its duration of 6 minutes and 23 seconds. The longest total solar eclipse of the 21st century so far was on 22 July 2009, lasting 6 minutes and 39 seconds.
The maximum possible duration for a solar eclipse is 7 minutes and 30 seconds. The longest eclipse expected before the year 3000 will occur on 16 July 2186, lasting 7 minutes and 29 seconds, and will be visible in South America north of Brazil, but not in Brazil itself.
The next total solar eclipse visible from Brazil will take place on 12 August 2045, with its band of totality crossing states in the North and Northeast regions and partiality visible across the rest of the country.
