Moonlight and Dark Skies: Why the Nights Around New Moon Are the Darkest

A dark sky is not only a matter of waiting for night. Two kinds of light compete with the faint stars: light from the Moon, and light from towns and cities. The Moon changes from night to night, and you can predict it. City light stays where it is, but you can drive away from it. Knowing both helps you choose when and where to look.

This guide explains why the nights around New Moon are the darkest, how a bright Moon and city lights wash out faint stars, and what NASA and NOAA say about finding a dark place. It ends with a task in the Rise & Set Dial.

Two lights that brighten the night

NASA's pages for Moon observers point out that the Moon is the brightest object in our night sky. That is why it matters so much when you want to see anything fainter.

The second light comes from people. NASA describes light pollution as stray light from urban areas that scatters into the night sky. It comes from parking lots, sport complexes, street lights and other human activity, and together it forms a glow. The larger and more developed a city is, the more light pollution it tends to produce. In bright urban skies, NASA says, only the brightest stars and planets are bright enough to see, and the fainter stars and the Milky Way are washed out.

You can do little about the Moon's schedule, but you can read it. You can also move away from the city. The next sections take the Moon first, then the city.

Where the Moon is at New Moon

The U.S. Naval Observatory (USNO) says New Moon occurs when the Sun and Moon are quite close together in the sky. The Moon's unlit side faces Earth. NASA adds the timing: in this phase the Moon is in the same part of the sky as the Sun, and it rises and sets with the Sun.

That means the Moon is above the horizon during the day and below it at night. NASA's JPL education pages put it vividly: during the new Moon phase the Moon is high overhead in the middle of the day. We do not see it, they explain, because the side facing Earth is not lit and because it is so bright outside.

Moonrise can happen at any time of day. USNO notes that this makes it often possible to see the Moon in daylight, and to have moonless nights. New Moon is the clearest case of a moonless night.

The drawing shows the day as a clock face with the rise and set times of the Sun and the Moon. At an age of 0 days, the dial's model gives the Moon the same rise and set times as the Sun, so at 11 PM neither one is up.

How a bright Moon hides faint stars

The opposite case is the Full Moon. USNO says a Full Moon rises about the time of sunset and sets about the time of sunrise for most places on Earth, so it is up for most of the night. NASA's guide to finding stargazing spots says that for the week or so before and after the full Moon, the Moon is quite bright and creates a lot of skyglow. The effect is similar to human-made light pollution, because it makes faint stars and other faint objects harder to see.

The same NASA guide names the best time to observe the stars, as far as the Moon's brightness goes: the two weeks before and after the new Moon phase. On those evenings the Moon is absent from the sky all night, or it sets within a couple of hours after sunset, or it does not rise until the pre-dawn hours. The wording is loose, so read it as a stretch of nights around New Moon rather than one fixed date.

NASA's list of rise and set patterns shows how each phase fits the night. The last column is a plain reading of those times.

NASA says these patterns hold at most latitudes and give only a rough estimate. For exact moonrise and moonset times, it says to check local predictions.

At an age of 14.77 days, the dial's model puts the Full Moon above the horizon at 11 PM, right where New Moon leaves an empty sky.

Light pollution and distance

City light fades with distance. NASA says the glow from light pollution diminishes as you move farther from a population center, so heading at least 20 to 30 miles (32 to 48 kilometers) from the city limits is key. A city 30 to 50 miles (48 to 80 kilometers) away can still put a dome of light on one horizon, while the opposite direction can be much darker. A ridge of mountains between you and the city can make a big difference too.

NASA also describes the Bortle scale, a numeric scale that tells stargazers how bright the sky is likely to be over a place. It has nine levels. Class 1 is the darkest sky you can find on Earth, and class 9 is the most light-polluted city sky. Under class 9 you see only the brightest stars and planets. For most people, NASA says, a class 3 or 4 location is dark enough for a great evening of stargazing.

NOAA reported the scale of the problem in 2016, when it covered a global atlas of light pollution published in the journal Science Advances. NOAA said light pollution blots out the Milky Way for eight in ten Americans, and that the Milky Way is hidden from one-third of humanity. That figure is a decade old, so treat it as a snapshot rather than today's count.

Planning a dark-sky night

Put the two lights together and a plan appears. Pick a night near New Moon, drive away from the city, and wait for the sky to settle. This checklist follows NASA's advice.

Even after sunset, full darkness takes time. USNO defines astronomical twilight as ending in the evening when the center of the Sun is 18 degrees below the horizon. After it ends, scattered light from the Sun is weaker than light from starlight and other natural sources. The twilight guide explains the three stages. So a truly dark sky needs three things at once: no Moon, a place far from city lights, and a time after astronomical twilight.

Common mistakes

• Thinking only the Full Moon night matters. The Full Moon rises at sunset and sets at sunrise, so it brightens the whole night, and NASA counts the week or so before and after it.
• Waiting for the exact minute of New Moon. NASA names the weeks around New Moon as the best time, not a single night.
• Blaming the Moon for everything. City light scatters into the sky too. NASA says to get at least 20 to 30 miles (32 to 48 kilometers) away.
• Starting right after sunset. Twilight light is still in the sky. USNO says it fades below starlight only after astronomical twilight ends.
• Using a bright flashlight. NASA says your eyes need half an hour or more to adapt, and red lamps disturb them least.

Try it in the instrument

Open the Rise & Set Dial and set the sky to the phase with the darkest nights: the Moon is up only in daytime. The target is a Moon age of about 0 days. USNO counts the Moon's age in days from New Moon.

Here is the relation. The dial models a middle-latitude place near an equinox, with the Sun up from about 6 AM to 6 PM. At an age of 0, the Moon rises and sets with the Sun, as NASA describes, so every night hour is moonless. Each day of age moves moonrise about 49 minutes later in the model, which matches NASA's average of about 50 minutes later each day.

That rule also shows why the window around New Moon is narrow. After three days at about 50 minutes a day, the Moon rises about two and a half hours later, and it sets about two and a half hours after the Sun. It is then still above the horizon in the early evening, a pattern that NASA's description of a waxing crescent confirms. Higher levels shrink the window, so a Moon a few days old will not match.

Questions people ask

Does New Moon mean total darkness?

No. The Moon gives no light at night, but starlight, scattered light from the Sun before astronomical twilight ends, and any light pollution remain. USNO says that after astronomical twilight, scattered sunlight is weaker than starlight and other natural sources.

Why can't I see the new Moon in the daytime sky?

It is there. NASA says it is up during the day, but its lit side faces away from Earth. JPL adds that the sky is also very bright, which hides it.

How far from a city should I go?

NASA says at least 20 to 30 miles (32 to 48 kilometers) from the city limits is key, because skyglow diminishes with distance. Mountains between you and the city help, and facing away from the city helps too.

How long do my eyes need to adjust to the dark?

NASA says half an hour or more. Bright phone screens and flashlights undo the adjustment, and red lamps and red LEDs have the smallest effect on night vision.

Sources

• How to Find Good Places to Stargaze, NASA Science. https://science.nasa.gov/solar-system/skywatching/how-to-find-good-places-to-stargaze/. Opened November 10, 2026.
• Moon Phases, NASA Science. https://science.nasa.gov/moon/moon-phases/. Opened November 10, 2026.
• Skywatching FAQ, NASA Science. https://science.nasa.gov/skywatching/faq/. Opened November 10, 2026.
• Observe the Moon at Home, NASA Science. https://science.nasa.gov/moon/observe-the-moon-night/observe-at-home/. Opened November 10, 2026.
• Observing the Moon, NASA JPL Education. https://www.jpl.nasa.gov/edu/resources/lesson-plan/observing-the-moon/. Opened November 10, 2026.
• Milky Way now hidden from a third of humanity, NOAA. https://www.noaa.gov/stories/milky-way-now-hidden-from-third-of-humanity. Opened November 10, 2026.
• Rise, Set, and Twilight Definitions, U.S. Naval Observatory, Astronomical Applications Department. https://aa.usno.navy.mil/faq/RST_defs. Opened November 10, 2026.
• Phases of the Moon and Percent of the Moon Illuminated, U.S. Naval Observatory, Astronomical Applications Department. https://aa.usno.navy.mil/faq/moon_phases. Opened November 10, 2026.

We opened each source ourselves on the date shown. The drawings are our own and were checked against the numbers in these sources.

Read next

• TwilightTwilight is the glow before sunrise and after sunset.
• Keeping a Sky LogNASA and JPL journals ask for little: the date, the time and a drawing, kept for a month.