This Thursday, March 26, the Moon is in its Crescent phase, one of the moments in the lunar cycle in which its luminosity gradually increases. Earth’s natural satellite entered this stage on Wednesday (25), at 4:19 pm, according to the National Institute of Meteorology (INMET). During this period, the celestial body forms an angle of approximately 90° in relation to the Earth and the Sun, which means that only part of its illuminated surface is visible.

This phenomenon does not happen because the Lua It changes shape, but because it orbits the Earth and, as it changes position in relation to the Sun, we start to see different parts of the half that is always illuminated by sunlight. In other words: the Moon remains the same, what changes is our point of view from here on Earth.

From thin crescent to crescent moon

From a scientific point of view, the Crescent phase includes two moments that usually attract attention in the sky: the thin crescent, right after the New Moon, and the so-called crescent, when the Moon appears to be cut in half.

Despite its appearance, this does not mean that only half of the Moon is illuminated. In fact, half of the Moon is always receiving light from the Sun, what varies is how much of this illuminated part we can see from Earth. In the crescent moon, for example, we see half of the illuminated face visible, which creates this characteristic impression.

Best time to observe the Moon Increasing

The Crescent Moon is usually more easily seen from late afternoon to early evening, gaining prominence shortly after sunset. As the days pass, it becomes increasingly brighter and remains in the sky for longer. For those observing from Brazil, there is still an interesting visual curiosity: the appearance of the Moon may look a little different compared to images taken in the Northern Hemisphere.

This happens because the orientation of the illuminated part changes depending on the observer’s position on the planet. The phase, however, is the same all over the world. In other words, everyone is seeing the Crescent Moon, but it may appear “lying down”, “standing up” or tilted, depending on the latitude and observation time. This detail usually raises doubts, but it is part of the geometry between the Earth, the Moon and the Sun.

An ideal phase to see surface details

The Waxing Moon is also usually a rich phase in detail for observation. As the Sun’s light hits the lunar surface from the side at this stage, the shadows in the craters and mountains become more evident, which helps to highlight the relief.

For amateur astronomers, this is one of the best times of the month to observe the Moon with binoculars or small telescopes. On many nights, it is also possible to notice a soft glow in the dark part of the lunar disk, a phenomenon known as cinereal light or earthshinecaused by sunlight reflected by the Earth itself and reflected off the surface of the Moon.