The Moon sits in its darkest phase, gathering energy for the crescents and fullness that will follow.
No último dia de janeiro de 2025, a Lua repousa em sua fase Nova — apenas 3% de sua face iluminada, quase invisível ao olho humano. É um momento de recomeço silencioso: em cinco dias, o primeiro crescente reaparecerá no horizonte ocidental ao entardecer, retomando o ritmo de 29,5 dias que governa o ciclo lunar há bilhões de anos. Janeiro já completou seu calendário lunar inteiro, do Crescente ao Cheia, do Minguante ao Nova — um ciclo dentro do ciclo, como sempre foi.
- A Lua está em sua fase mais escura do mês, com apenas 3% de visibilidade em 31 de janeiro de 2025, quase apagada no céu noturno.
- Janeiro encerrou um ciclo lunar completo em apenas um mês: Crescente (dia 6), Cheia (dia 13), Minguante (dia 21) e Nova (dia 29).
- Em cinco dias, o Crescente Crescente marcará o retorno da luz lunar, sinalizando a próxima etapa do ciclo de 29,5 dias.
- O ciclo lunar não é perfeitamente regular — a órbita elíptica da Lua faz com que cada lunação varie levemente em duração, embora o padrão anual se mantenha estável.
No último dia de janeiro, a Lua encontra-se em sua fase Nova: apenas 3% de sua superfície captura a luz do Sol, tornando-a quase imperceptível no céu. É um momento de transição silenciosa — em cinco dias, o Crescente Crescente surgirá no horizonte ao entardecer, e o ciclo recomeçará.
Janeiro foi um mês lunar completo. O Crescente abriu o mês no dia 6, a Lua Cheia brilhou intensa no dia 13, o Minguante chegou no dia 21, e a Lua Nova se instalou no dia 29 — tudo isso em menos de 30 dias, segundo dados do Instituto Nacional de Meteorologia do Brasil.
O ciclo lunar, chamado de lunação pelos astrônomos, dura em média 29,5 dias e percorre oito fases: quatro principais — Nova, Crescente, Cheia e Minguante — e quatro intermediárias, como o Crescente Crescente e o Crescente Minguante. A duração exata de cada ciclo varia levemente, pois a órbita da Lua não é um círculo perfeito; ela é influenciada pela gravidade da Terra e do Sol. Ainda assim, o padrão se repete com fidelidade ao longo dos meses e dos anos.
Enquanto janeiro se encerra, a Lua permanece em seu momento mais sombrio — reunindo, por assim dizer, energia para os crescentes e a plenitude que virão a seguir.
On the last day of January, the Moon sits in its New phase—barely visible, just 3 percent of its face catching sunlight as it begins its slow climb back toward brightness. In five days, the Waxing Crescent will arrive, and the lunar cycle will resume its familiar march across the sky.
This moment marks the tail end of January's lunar calendar, a month that has already cycled through all four of the Moon's primary phases. The month opened on January 6 with the Waxing Crescent, arriving at 8:57 p.m. A week later, on January 13 at 7:27 p.m., the Full Moon hung heavy and bright. The Waning Moon followed on January 21 at 5:32 p.m., and then came this New Moon on January 29 at 9:37 a.m.—just two days before the month's end.
The rhythm governing all of this is the lunar cycle, or lunation, as astronomers call it. On average, this cycle stretches across 29.5 days, beginning when the Moon sits between Earth and Sun (invisible to us) and ending when it has wheeled all the way around and returned to that same position. During those 29.5 days, the Moon passes through four main phases, each lasting roughly seven days. But the cycle is more intricate than that. Between the New and Full Moon lie two intermediate phases: the Waxing Crescent and the Waxing Gibbous. Between the Full and New Moon come the Waning Gibbous and the Waning Crescent. These eight positions—four primary, four intermediate—map the Moon's journey across our sky.
What makes the lunar cycle subtly variable is that 29.5 days is only an average. The Moon's orbit is not a perfect circle; it wobbles slightly, pulled by Earth's gravity and by the gravity of the Sun. Some months the cycle completes in slightly less time, other months it takes slightly longer. But over the course of a year, the pattern holds.
The data tracking January's lunar phases comes from Brazil's National Institute of Meteorology, the official source for such observations. As January closes, the Moon sits in its darkest phase, nearly invisible, gathering energy for the crescents and fullness that will follow. In five days, the first sliver of light will reappear on the western horizon at sunset, and the cycle will begin again.
Notable Quotes
A lunation or lunar cycle is subtly variable, with an average duration of 29.5 days, during which the Moon passes through four main phases, each lasting approximately seven days.— National Institute of Meteorology (Inmet)
The Hearth Conversation Another angle on the story
Why does the Moon's cycle take exactly 29.5 days? Is there something special about that number?
It's the time it takes for the Moon to return to the same position relative to Earth and the Sun. But it's not perfectly regular—the Moon's orbit is slightly elliptical, so some cycles run a bit shorter, others longer. 29.5 days is just the average.
So when you say the Moon is 3 percent visible today, what does that actually mean?
It means only a tiny sliver of the sunlit side is facing us. The Moon is between Earth and the Sun right now, so almost all of its lit hemisphere is turned away. In five days, as it moves in its orbit, more of that lit side will come into view.
The article mentions "interfases"—what are those?
They're the in-between phases. Between New and Full, you get the Waxing Crescent and then the Waxing Gibbous. Between Full and New, the Waning Gibbous and Waning Crescent. Each main phase lasts about seven days, but these intermediate phases fill in the gaps and give you a more precise picture of where the Moon is in its cycle.
Does the lunar cycle affect anything on Earth?
That's beyond what this report covers, but the cycle has governed human timekeeping for millennia. Months are named after it. Tides follow it. Cultures have organized festivals and harvests around it.
Why does the article mention the National Institute of Meteorology as the source?
Because they're the official Brazilian authority on atmospheric and astronomical observations. When you want to know what phase the Moon is in on a given day, you go to the institution that tracks it.