This Wednesday, December 24, 2025, Lua is in phase Nova. The satellite has around 15% of its surface illuminated and continues in a process of gradual growth. The Essa configuration occurs because the Lua is positioned between the Terra and the Sol, with the illuminated side facing the king star. Reduced visibility makes observation difficult with the naked eye, but it marks the beginning of a new lunar cycle.
Phase Nova appeared on December 19th, at 10:43 pm (Brasília time). Desde then, the visible portion has progressively increased. Faltam only three days for the transition to Lua Crescente, scheduled for December 27th, at 4:09 pm (Brasília time). Essa evolution follows the pattern of the lunar calendar month.
Complete calendar of Lua phases in December 2025
The month of December recorded four main phases. The cycle started with Lua Cheia on the 4th, at 8:14 pm (Brasília time). Essa phase brought full illumination of the lunar disk visible from Terra.
Lua Minguante arrived on the 11th, at 5:51 pm (Brasília time). Nessa step, the illumination gradually decreased as the satellite moved away from the position opposite Sol.
Lua Nova occurred on the 19th, at 10:43 pm (Brasília time). Esse moment represents the alignment of Lua between Terra and Sol. Visible illumination is minimal or non-existent initially.
Lua Crescente is scheduled for the 27th, at 4:09 pm (Brasília time). From there, the illuminated portion will continue to grow until the next Lua Cheia.
How the main phases of the lunar cycle work
The lunar cycle, also known as lunation, has an average duration of 29.5 days. Nesse interval, the Lua passes through the four main phases. Cada one lasts approximately seven days.
Lua Nova marks the beginning of the cycle. The satellite is invisible or barely visible because the illuminated face points to Sol. The lighting increases progressively over the following nights.
Lua Crescente appears next. A thin band of light appears and expands night after night. Growth continues until reaching half illumination at Quarto Crescente.
Details of intermediate phases and variations
Between Lua Nova and Cheia the interfaces of Quarto Crescente and Crescente Gibosa occur. Nessas steps, more than half of the disc is illuminated. The light gradually intensifies.
From Lua Cheia to Minguante, the interfaces of Minguante Gibosa and Quarto Minguante arise. Lighting decreases in a similar way, but in the opposite direction.
The complete cycle ends when Lua returns to phase Nova. Essa periodicity results from the relative position between Lua, Terra and Sol. The subtle variation occurs due to the elliptical orbit of Lua.
Why Lua Nova on December 24th has 15% visibility
Five days after the exact Lua Nova, illumination already reaches 15%. The percentage grows daily as Lua moves in its orbit. Essa setting allows you to observe a thin crescent on the horizon after sunset.
Observation is favored in places with clear skies and no light pollution. The phenomenon follows the average orbital movement of Lua. Current visibility confirms progress to phase Crescente.
Characteristics of Lua Nova and observational implications
At Lua Nova, the satellite does not reflect light directly to Terra. Alignment with Sol precludes common nighttime viewing. Essa phase begins a new period of progressive lighting.
The transition to increasing visibility occurs steadily. On December 24, 15% already allows detection in ideal conditions. The cycle continues until the lunation is complete.
