What is a New Moon? Unveiling the Mystery of the Invisible Lunar Phase

While a new moon itself remains unseen in the night sky, its arrival marks the perfect time for stargazing. The darkness it brings creates ideal conditions for observing the wonders of the universe. (Image credit: by-studio via Getty Images)

Have you ever looked up at the night sky and noticed the absence of the moon? This seemingly empty space is when the moon is in its new moon phase. Often misunderstood as simply a “dark moon,” the new moon is a crucial part of the lunar cycle and plays a significant role in various celestial events and even cultural practices. But What Is A New Moon exactly, and why can’t we see it?

When is the Next New Moon?

Mark your calendars! The next new moon will grace our skies on Thursday, February 27th at 7:45 p.m. Eastern Daylight Time (EDT), which translates to 00:45 Greenwich Mean Time (GMT) on February 28th. This precise timing is when the moon reaches a specific point in its orbit, setting the stage for the next lunar cycle to begin.

Defining the New Moon: Alignment and Invisibility

A new moon occurs when our celestial neighbor, the moon, positions itself directly between Earth and the sun. In this alignment, the side of the moon that is illuminated by the sun faces away from us. Imagine holding a ball between a lamp and yourself; if you are positioned so the shadow side of the ball is facing you, you wouldn’t be able to see the illuminated part. This is essentially what happens during a new moon.

This positioning means that the moon’s sunlit side is facing away from Earth, and the side facing us is in shadow. As a result, the new moon appears virtually invisible to the naked eye from Earth, blending seamlessly with the darkness of the night sky. The only exception to this invisibility is during a solar eclipse, when the new moon passes directly in front of the sun, creating a breathtaking silhouette against the solar disk.

The monthly cycle of new moons is a natural consequence of the moon’s orbit around Earth. It takes approximately one month for the moon to complete a full orbit, and during each orbit, it passes through the new moon phase. However, it’s important to note that due to the slight tilt of the moon’s orbit relative to Earth’s orbit around the sun, a solar eclipse doesn’t occur every month. NASA explains that this tilt is why the moon doesn’t always perfectly block the sun during each new moon phase.

The Best Time for Skywatching: New Moon Darkness

Ironically, the “invisible” new moon provides the most optimal conditions for stargazers. With the moon absent from the night sky, there is no lunar glare to obscure faint celestial objects. This makes the nights surrounding the new moon ideal for observing stars, galaxies, and other deep-sky wonders. For astronomy enthusiasts, the new moon is not a time of lunar absence, but rather a period of enhanced visibility for the rest of the cosmos.

Earthshine: A Glimmer During the New Moon Phase

While the new moon itself is dark, the days just before and after it can reveal a beautiful phenomenon known as Earthshine, sometimes poetically referred to as the “Da Vinci glow” or “the old moon in the new moon’s arms.” During this time, a faint, ethereal glow can be seen illuminating the entire disk of the moon, even though only a sliver of crescent is directly lit by the sun.

This subtle illumination is caused by sunlight reflecting off the fully illuminated Earth and onto the lunar surface. From the moon’s perspective during this phase, Earth is nearly full and bright, casting a soft glow onto the moon’s dark side. Space.com’s skywatching columnist Joe Rao provides a detailed explanation of Earthshine in an interview with FoxWeather.com, highlighting the delicate beauty of this lunar phenomenon.

Black Moons: When New Moons Get Rare

Occasionally, you might hear the term “Black Moon” associated with the new moon phase. While not an official astronomical term, “Black Moon” commonly refers to two distinct new moon events, as defined by Time and Date:

1. The second new moon within a single calendar month: This occurs when the lunar cycle aligns in such a way that two new moons happen within the same month.
2. The third new moon in a season with four new moons: This definition is less common but refers to a seasonal pattern where a season (like spring, summer, fall, winter) contains four new moons instead of the usual three, and the third one is termed a Black Moon.

According to the seasonal definition, the next Black Moon is expected on August 23, 2025. These “Black Moons” are relatively rare occurrences, adding a touch of intrigue to the lunar cycle.

(Image credit: Celestron) Interested in exploring the moon and beyond? The Celestron Astro Fi 102 telescope is a top recommendation for beginners in our guide to the best beginner telescopes. And for enhanced lunar viewing, consider a moon filter!

For those eager to observe the moon or other celestial wonders, resources are readily available. Explore guides on binoculars deals and telescope deals to equip yourself for skywatching. If astrophotography is your interest, our guides to the best cameras for astrophotography and lenses for astrophotography can help you capture stunning lunar images.

To delve deeper into lunar observation, consult our comprehensive guide to observing the moon. This resource can assist you in planning your lunar explorations, whether you aim to study lunar seas, mountainous regions, or impact craters.

And for those seeking pristine dark skies away from city lights, our list of 21 amazing dark sky reserves around the world offers a gateway to exceptional stargazing locations.

New Moon Calendar 2025: Dates to Remember

Here are the new moon dates for 2025, according to NASA, allowing you to plan your skywatching sessions:

Understanding Moon Phases: A Lunar Cycle

The moon’s phases as it orbits Earth, starting from the new moon. (Image credit: NASA)

As the moon orbits Earth, its appearance changes in a predictable cycle of moon phases. These phases are determined by the relative positions of the sun, Earth, and moon, and how much of the sunlit side of the moon is visible from our perspective. The eight primary moon phases are:

• New moon: As we’ve discussed, the moon is between Earth and the sun. Only Earthshine dimly lights the side facing us, making it mostly invisible.

• Waxing crescent: A sliver of the moon becomes visible, and the illuminated portion grows each night (“waxing”) in a crescent shape.

• First quarter: Half of the moon is illuminated. At this point, the moon has completed about a quarter of its orbit since the new moon.

• Waxing gibbous: More than half of the moon is illuminated, and the lit portion continues to increase (“waxing gibbous”).

• Full moon: The Earth is between the sun and the moon. The side of the moon facing Earth is fully illuminated by the sun, making it appear as a bright disk. When the alignment is perfect, Earth’s shadow can cause a lunar eclipse.

• Waning gibbous: After the full moon, the illuminated portion starts to decrease (“waning”), but more than half remains lit (“gibbous”).

• Last quarter: Again, half of the moon is illuminated, but it’s the opposite half compared to the first quarter. The moon is now three-quarters of the way through its cycle since the new moon.

• Waning crescent: The illuminated sliver continues to shrink (“waning crescent”) until it disappears entirely, returning to the new moon phase and starting the cycle anew. Occasionally, when the new moon passes directly in front of the sun, we experience a solar eclipse.

New Moon FAQs Answered by an Expert

To further clarify the nuances of the new moon, we consulted with meteorologist and skywatching expert, Joe Rao.

What’s the difference between a new moon and a full moon?

Joe Rao explains: “When the moon is in its new phase, it’s positioned between the sun and Earth, appearing near the sun in our sky. Thus, a new moon rises and sets roughly with the sun and is invisible because the sunlit side faces away from us. We call it ‘new’ because the 29.53-day lunar cycle, known as a synodic month, restarts. Synodic comes from the Greek ‘sunodos,’ meaning ‘meeting.’ About every 29½ days, the moon ‘meets’ the sun, beginning a new lunar phase cycle – hence, a ‘new’ moon.”

“Conversely, a full moon is opposite the sun in the sky. It rises at sunset, peaks in the middle of the night, and sets at sunrise. The Earth-facing side is fully illuminated, hence ‘full’ moon.”

How long does a new moon last?

Joe Rao clarifies, “Astronomers pinpoint the new moon moment based on its sky position relative to the sun. New moon occurs when the sun and moon share the same right ascension. However, because the moon is constantly orbiting Earth, the precise new moon phase is instantaneous. Visibility is different; we usually need 18-24 hours after the new moon for it to move far enough from the sun to become visible as a slender crescent in the western sky after sunset.”

“There’s another way to ‘see’ a new moon: during a solar eclipse. The dark disk of the new moon, normally unseen monthly, becomes visible in silhouette as it crosses the sun’s face.”

Referencing astronomer Leslie C. Peltier, Rao adds, “Peltier noted, ‘Only during a solar eclipse can we note the instant when the old moon crosses the sun’s midline and becomes a fresh new moon.'”

How often do we experience a new moon?

“Usually monthly,” says Rao. “If a new moon falls on the 1st or 2nd of a month, a second new moon might occur at month’s end. Only February can potentially lack a new moon. Even in leap years, February has at most 29 days. Since a synodic month is about 29.5 days, a new moon on January 30th or 31st could push the next one to March 1st, skipping February entirely! This rare event will happen in 2033.”

Additional Resources

For a comprehensive lunar calendar and other celestial events, explore NASA’s SkyCal Events Calendar.

Editor’s Note: Share your moon photos with Space.com readers! Send images, comments, name, and location to [email protected].

References

• When Is the Next Black Moon? Time and Date, https://www.timeanddate.com/astronomy/moon/black-moon.html
• When and where to spot the ‘Di Vinci Glow’, Fox Weather, https://www.foxweather.com/watch/play-6669f25650000cb
• Lunar Phases, NASA, https://solarsystem.nasa.gov/moons/earths-moon/lunar-phases-and-eclipses/#otp_what_are_lunar_phases?

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