Between Tuesday night (17) and the early hours of Wednesday (18), Brazilians will have the opportunity to follow another astronomical phenomenon: the last lunar eclipse of the year. A partial lunar eclipse occurs when only part of the Moon passes through the Earth's dark shadow.

However, observing this landscape will not be easy due to weather conditions. In the capital, São Paulo, for example, the weather forecast indicates cloud cover after a period of rain on Sunday (15) and Monday (16). Within the state, as well as other parts of the country, the problem is the accumulation of smoke from forest fires.

This pollution has already changed the color of the Sun and Moon, leaving them reddish. In these locations, it will also not be possible to observe the eclipse clearly, because it will not be total, meaning that the Earth's satellite will not witness significant visible changes.

According to astronomer Josina Nascimento, from the National Observatory, this partial eclipse will cover only 3.5% of the total area of ​​the moon, the part that will be completely dark. The rest of the moon will have a darker color. This happens because an eclipse of this type has two phases: the umbra and the penumbra.

“The penumbra is a lighter shadow, it receives some light from the Sun, so when the Moon is in the penumbra (whether it is totally or partially in the penumbra) you cannot see any change with the naked eye (without using instruments) We call this phase the penumbra phase. There are eclipses that are only penumbra. In other words, the Moon penetrates the penumbra and then leaves the penumbra,” explains Nascimento.

In the event of this week's eclipse, 3.5% of the coverage will be in the shadow phase and 96.5% in the penumbra phase.

The next total lunar eclipse, in which the Moon enters the umbra entirely, will only be visible from Brazil on March 14, 2025. What's notable about this type of eclipse is the fact that the moon takes on an orange or reddish hue. The redder color is due to the concentration of dust and clouds in Earth's atmosphere, according to NASA.

This Tuesday's solar eclipse will have penumbral, partial and penumbral phases again, at the following times (Brasilia):

• The partial eclipse begins at 9:41:07 PM.

• The partial eclipse begins at 11:12:58 PM.

• Maximum partial eclipse at 11:44:18 PM.

• Partial eclipse ends on the 18th at 0:15:38

• End of penumbral eclipse on 18th at 1:47:27

No special equipment is needed to watch the eclipse, Josina explains. Observers can look directly at the moon without worry, because, unlike a solar eclipse, there are no risks to our eyes. But anyone with binoculars or a telescope, and the weather helps, will have a better view.

“Events like lunar eclipses are great opportunities to awaken people’s curiosity about space. They allow anyone, without any equipment, to observe astronomical phenomena and better understand the dynamics between the Earth, the Sun and the Moon, and are a great opportunity to promote science and astronomy,” says the astronomer.

As usual, the National Observatory will broadcast the eclipse live on its website. YouTube ChannelAnyone in a place where the sky is overcast, due to clouds or pollution, will have the opportunity to watch the show.