Astronomy

Sunset moonrise what happens in between?

Sunset moonrise what happens in between?


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Here in south London I have just seen that the sun will set at 16:45 hrs but the moonrise does not happen until 2hrs later 18:45 hrs what is happening in this two hour void, will it be too dark to see?


Whether it is light enough to see will depend on the local streetlights and the lights coming from buildings, etc If you are in a city named South London there will be plenty of light.

The period shortly after sunset is called twilight because light from the sun below the horizon is still being reflected downwards, so it will take time for the sky to turn black.

And it is possible that someone could see well enough to walk around by starlight. Decades ago I used to walk up a hill to watch the stars through binoculars. So obviously there was enough light for me to see where I was going, light from the stars and maybe from nearby light sources in the neighborhood.

Anyway, if this place, South London, is a populated community, there should be enough light from various local sources to see where you are going. And possibly the interval between sunset and moonrise might be the best time to look at the stars, if light pollution from the neighborhood doesn't make them invisible.

When I go to bed at night my bedroom is almost totally dark. But if I wake up in the night I can see much better in my bedroom, because my eyes have become dark-adapted while I slept. So if you are in the dark your eyes should gradually adapt to seeing in the dark and you should start to see things better.


The Moon rises approximately 50 minutes later every night. Simplistically, the new moon will rise and set roughly with the Sun, while the full moon will be opposite the Sun (as in, it will rise when the Sun sets, and set when the Sun rises). Look at the Moon the next night and it should be rising about 19:35 from the day mentioned in your question.

This +50 minute time is due to the Moon's orbit around Earth, which takes roughly 29 days.


Sunset moonrise what happens in between? - Astronomy

I have been enjoying the moon rise for 4 or 5 evenings recently. Our house is situated with mountains to the east so it is very easy to "mark" the spot on the horizon where the moon comes up each evening. QUESTION: Why is there such a great variation in the place on the horizontal plane where the moon rises from one evening to the next? There has been as much as 25 degrees or more difference in the spot that the moon clears the horizon from one evening to the next.

The position of Moonrise and Moonset, like that of Sunrise and Sunset varies as the Earth goes around the Sun, but also with the phases of the Moon.

Let's start with the position of Sunrise/Sunset, which varies as the Earth orbits the Sun. Because the Earth is inclined at an angle of 23.5 degrees to the plane of its orbit, and because the direction of the inclination (with respect to the stars) does not change as the Earth moves around the Sun, sometimes the Earth is tilted towards the Sun and sometimes it is tilted away from it. This cause the Sun to take different paths across the sky across the year and gives us seasons. In the Northern hemisphere the pattern of the position of Sunrise/Sunset is as follows (in the Southern hemisphere exchange North for South and vice versa):

Season Position of Sunrise/Sunset
Winter Southeast/Southwest
Spring East/West
Summer Northeast/Northwest
Autumn East/West

Only on the equinoxes (Sept/Mar 21st) does the Sunrise/set at due East/West. At the solstices (Dec/June 21st) the position is its furthest South/North of East/West. How far to the North or South that is depends on your lattitude. There are other posted answers on this here, and here.

Now lets get to the Moon. The time of day that the Moon rises or sets depends on its phase. This should be obvious when you remember that the phase of the Moon depends on the relative positions of the Sun, Moon and Earth. For example when the Moon is Full it is opposite the Earth from the Sun, so when the Sun sets, the Moon must rise and vice versa. Here is a table summarizing that:

Moon phase Moonrise Moonset
New Sunrise Sunset
1st quarter Local noon Local midnight
Full Sunset Sunrise
3rd quarter Local midnight Local noon

By local noon and local midnight I mean the points when the Sun crosses the meridian, and exactly 12 hours later. This can be different from the time on your watch because we define time zones which all use the local time at the centre of the zone.

So when the Moon is new, it rises and sets with the Sun, and the position of Moonrise/set varies just like that of Sunrise/set. When the Moon is full however the pattern is inverted. To be more explicit (again here this is for the Northern hemisphere, for the South exchange North for South):

Season Postion of Moonrise/set
NEW 1st FULL 3rd
Winter Southeast/Southwest East/West Northeast/Northwest East/West
Spring East/West Northeast/Northwest East/West Southeast/Southwest
Summer Northeast/Northwest East/West Southeast/Southwest East/West
Autumn East/West Southeast/Southwest East/West Northeast/Northwest

Like the Sunrise/set positions, the amount of variation depends on your lattitude.

This page was last updated on July 18, 2015.

About the Author

Karen Masters

Karen was a graduate student at Cornell from 2000-2005. She went on to work as a researcher in galaxy redshift surveys at Harvard University, and is now on the Faculty at the University of Portsmouth back in her home country of the UK. Her research lately has focused on using the morphology of galaxies to give clues to their formation and evolution. She is the Project Scientist for the Galaxy Zoo project.


Watch for Mars and the full Harvest Moon

Depending on where you live worldwide, the upcoming full moon will fall on October 1 or 2, 2020. For the Northern Hemisphere, this full moon counts as our Harvest Moon (full moon nearest the September equinox) and the first full moon of the autumn season. For the Southern Hemisphere, it’s the first full moon of spring. No matter where you live, look for a full-looking moon to light up the nighttime from dusk until dawn these next few nights. What’s more, that nearby brilliant red “star” to the east of the moon is no star at all. It’s the red planet Mars, now poised to reach its once-in-two-years opposition in our sky.

Mars will come to opposition – when Earth will swing between the sun and Mars – on October 13, 2020. At that time, the red planet will be rising in the east as the sun is setting in the west. Around now – just two weeks shy of opposition – Mars is rising near the time of sunset. It’s dazzlingly bright (brighter than all the stars, and even brighter than Jupiter), and it’s fiery red in color. You can’t miss Mars as the bright, red, starlike object ascending in the east each evening. Mars will be brighter at this year’s opposition than it will be again until the year 2035. Read more about Mars and its 2020 opposition.

And now … about that Harvest Moon in early October. In 2020, it’s a precursor to a Blue Moon on October 31. That’s because – when there are two full moons in a single calendar month – many people call the second one a Blue Moon. Read more: When is the next Blue Moon?

(If you live in the far-eastern part of the globe – eastern Australia, New Zealand – the second and third full moons of the spring season actually come in early and late November 2020, meaning the second full moon of November 2020 counts as your Blue Moon.)

Astronomers define a season as the time period between an equinox and a solstice, or vice versa. Typically, there are three full moons in one season. In 2020, the season between the September 2020 equinox and the December 2020 solstice harbors the typical three full moons.

September 2020 equinox: September 22 at 13:31 UTC
Full moon: October 1 at 21:05 UTC (Harvest Moon)
Full moon: October 31 at 14:49 UTC (monthly Blue Moon)
Full moon: November 30 at 09:30 UTC
December 2020 solstice: December 21 at 10:02 UTC

Next year, in 2021, the full moons will come about 11 calendar days earlier than in 2020. Therefore, it should come as no surprise that next year’s sole September full moon will fall on September 20, 2021 (11 days previous to October 1). This will also be the Northern Hemisphere’s full Harvest Moon, but the last full moon of the summer season (instead of the first full moon of autumn). Moreover, four full moons (instead of the typical three full moons) will fall between the June 2021 solstice and the September 2021 equinox.

June 2021 solstice: June 21 at 03:32 UTC
Full moon: June 24 at 18:40 UTC
Full moon: July 24 at 2:37 UTC
Full moon: August 22 at 12:02 UTC (seasonal Blue Moon)
Full moon: September 20 at 23:55 UTC (Harvest Moon)
September 2021 equinox: September 22 at 19:21 UTC

It is somewhat rare to have four full moons in one season, so some people call the the third of a season’s four full moons a Blue Moon. Almanac makers chose to call third full moon (instead of the fourth full moon) of the season a Blue Moon, so that full moon nomenclature would match up with the season’s other three full moons.

Typically, a calendar year harboring a monthly Blue Moon (second of two full moons in one month) precedes a calendar year with a seasonal Blue Moon (third of four full moons in one season). Looking ahead to the year 2023, the monthly Blue Moon on August 31, 2023, will be followed by the seasonal full moon on August 19, 2024 and looking ahead to the year 2026, the monthly Blue Moon on May 31, 2026, will be followed by a seasonal Blue Moon on May 20, 2027.

In the meantime, the Northern Hemisphere’s Harvest Moon is always the full moon falling the closest to the autumnal equinox, whether it be the last full moon of summer or the first full moon of autumn. This year’s Harvest Moon turns exactly full on October 1, 2020, at 21:05 UTC. Although the moon turns full at the same instant worldwide, the clock time of the full moon varies by time zone. At Northern American and U.S. times zones, that places the full moon instant during our daytime hours (when the moon is still below our horizon) on October 1 at 6:05 p.m. ADT, 5:05 p.m. EDT, 4:05 p.m. CDT, 3:05 p.m. MDT, 2:05 p.m. PDT, 1:05 p.m. Alaskan Time and 11:05 a.m. Hawaiian Time.

Day and night sides of Earth at the instant of full moon (October 1, 2020, at 21:05 UTC). The shadow line at right (crossing eastern Asia and Australia) depicts sunrise October 2, while the shadow line at left (crossing Greenland and eastern South America) is sunset October 1. Graphic via EarthView.

Any full Harvest Moon tends to rise in the east around sunset and to set in the west around sunrise. On the nights following the Northern Hemisphere’s full Harvest Moon, the waning gibbous moon rises farther and farther north along the eastern horizon each day for about a week. For the Northern Hemisphere, these more northerly moonrises reduce the lag time between successive moonrises to yearly minimum (and in the Southern Hemisphere, these more northerly moonrises increase the lag time to a yearly maximum).

The narrow angle of the ecliptic as the sun sets at or near the autumn equinox means the moon rises noticeably farther north on the horizon from one night to the next. So there is no long period of darkness between sunset and moonrise for several days in a row. Image via classicalastronomy.com.

Whereas the effect is minimal in the tropics, the Harvest Moon phenomenon is more profound at high latitudes. On the average, the moon rises some 50 minutes later daily. But at 40 degrees north latitude, the moon presently rises some 25 minutes (instead of 50 minutes) later daily. At and around 60 degrees north latitude, moonrise comes at or nearly the same time for about a week.

Denver, Colorado (40 degrees north latitude)
Moonrise September 30: 6:40 p.m. MDT (Mountain Daylight Time)
Moonrise October 1: 7:03 p.m. MDT
Moonrise October 2: 7:27 p.m. MDT
Moonrise October 3: 7:51 p.m. MDT
Source: Old Farmer’s Almanac

The Harvest Moon phenomenon happens because the ecliptic – approximate monthly pathway of the moon – intersects the horizon at its shallowest angle of the year at sunset on the autumn equinox. At the equator and the tropical regions of the world, however, the ecliptic always intersects the horizon at a steep angle, so the Harvest Moon effect there is negligible. But at and near the Arctic Circle, the ecliptic pretty much parallels the horizon at sundown at this time of year, meaning the moon rises close to the same time for days on end. At far-northerly latitudes, it’s even possible for the moon to rise earlier day by day. Check out Fairbanks, Alaska, below!

Fairbanks, Alaska (65 degrees north latitude)
Moonrise September 30: 7:57 p.m. AKDT (Alaska Daylight Time)
Moonrise October 1: 7:54 p.m. AKDT
Moonrise October 2: 7:51 p.m. AKDT
Moonrise October 3: 7:49 p.m. AKDT
Source: Old Farmer’s Almanac

Want to know the sunset/moonrise times for your part of the world? Click here to find a sky almanac.

Ar Fairbanks, Alaska (65 degrees north latitude), the ecliptic pretty much aligns with the horizon at sunset. Therefore, around the Harvest Moon, the moon rises at or near the same time for a number of days in a row.

In the days before electricity, farmers at northerly latitudes counted on the lamp of the Harvest Moon to gather their crops. Making up for the autumn season’s waning daylight, the Harvest Moon faithfully provides several nights of dusk-till-dawn moonlight. This bonanza of moonlit nights remains the legacy of the Harvest Moon!

Bottom line: The full Harvest Moon will appear near bright red Mars on October 1-2, 2020.


This Week’s Night Sky: See Planets Line Up at Sunset

Also this week, watch out for early-bird meteors and Earth lighting up the moon’s dark side.

Worlds Align. Skywatchers will get a great observing challenge at sunset on August 1, as Jupiter, Mercury, and Venus form a diagonal line in the very low western horizon.

Since Venus and Mercury will be battling the glare of the setting sun, the best views of these two innermost worlds in the solar system will be had through binoculars. Venus will be only about five degrees above the local horizon, equal to the width of your clenched fist held at arm’s length. The entire planetary lineup will stretch about 27 degrees across the sky, roughly as wide as the space between your thumb and little finger when stretched apart and held at arm’s length.

As an added challenge, see if you can spot Regulus, the lead star in the constellation Leo, the lion, crashing the planet party. Look for Regulus halfway along an imaginary line between Venus and Mercury. The star will seem faint by comparison and will be embedded in the glare of sunset, so it may be difficult to spot depending on your local viewing conditions. The best viewing opportunities will be for observers in southerly latitudes, such as the southern U.S. and Central America.

Perseids Start. As of August 3, look for early-bird shooting stars belonging to the Perseid meteor shower during the overnight hours. While the official peak is still over a week away, patient skywatchers should be able to spot at least a half dozen meteors an hour between local midnight and the pre-dawn hours. Stay tuned for a full viewer’s guide next week.

Venus Meets Leo. Head outside 15 to 20 minutes after local sunset on August 4 and see if you can spot a stunningly close encounter between the planet Venus and the bright star Regulus. The pair will appear to be separated by just one degree, equal to two lunar disks. Check out this cosmic duo the next night and you will notice that they have switched positions in the sky.

Moon and Mercury. As twilight sets in on August 4, you can also try your hand at viewing a razor-thin crescent moon next to the faint planet Mercury. The pair will appear to be only six degrees above your local horizon, and the two objects will be only two degrees apart, equal to the width of your two middle fingers held at arm’s length. While Mercury may be a challenge to locate with the naked eye, binoculars will make the search easy thanks to the moon pointing the way.

Jupiter Duo. By August 5, the widening crescent moon will form a viewing treat as it appears to hang just below Jupiter in the darkening skies. The pairing of these two worlds should be quite eye-catching, as they will be only one degree apart, a spacing easily filled by the width of your thumb held at arm’s length.

Also see if you can view what is known as Earthshine, when you can see the darker portion of the crescent moon thanks to sunlight reflecting off Earth and all its reflective clouds, ice, and oceans.


Ankita Anirban has helped us paint the picture of an answer to this question from Manik. It was over to painter and creator of the series Dinotopia, James Gurney, and physicist William Livingston to shed light on the situation.

Ankita - First we put it to the forum, and got your suggestions. Evan_au suggests looking at the time stamp on your photo - which I think is cheating! ChiralSPO recommends looking for known landmarks, but that methods relies on you already knowing something about the landscape. We turned to James Gurney, painter and creator of the series Dinotopia, to ask him for his thoughts on this.

James - There's nothing fundamentally different about the light effects at sunset or sunrise, and there's no way to tell which you're looking at from the light and colour effects alone. The cause of those light effects are the same. Sunlight travels through more atmosphere as the rays approach the horizontal. Passing through more air scatters out more blue wavelengths from the light rays, making the light that remains appear increasingly orange or red. Of course, this effect happens both at sunrise and at sunset when colours are at their richest.

A single photo or a painting may be able to tell you about the altitude, the cardinal direction of the Sun, and about the height and distribution of cloud layers. And some art historians have argued that paintings of sunsets after the eruption of Krakatoa in 1883 reveal colours that were more pronounced worldwide. But it can't tell you whether it's morning or evening.

Ankita - If there are differences between sunrise and sunset, they're qualitative and subjective. In some environments, humidity and dust may be stirred up at the end of the day because of evaporation and turbulence, and these effects can increase the saturation of the colours. But you wouldn't be able to guess that from a single image.

James - Emotional subjectivity also plays a part in our human perception of sunsets and sunrises as we experience them in time. While a sunset builds gradually to a dramatic crescendo before quickly transitioning to twilight, a sunrise starts off with a blast of colour and, as Wordsworth says, the "vision splendid" fades "into the light of common day".

Ankita - What about the Moon? Can you tell whether it’s moonrise or moonset from a picture? William Livingston, from the National Solar Observatory in the USA, wrote in to tell us this:

“In the case of the Moon, every society has a favourite imagined figure marking the full Moon. In the Orient and Europe it is a hare. To North Americans, it is “the Lady in the Moon”. At Moonrise, she is seen in profile, looking downward. At Moonset, her gaze is upward”.

Next week, we’ll be answering a question from Saugatt.

Saugatt - Hi, Chris, this is Saugatt from Nepal, and my question is - because of the monsoon, the death toll raised to around 150 in India, Nepal, Pakistan and Bangladesh. What is the exact cause of monsoon rain, and how will it be affected because of global warming?"


Why Is The Sunset Red?

Why is the sunset red? Awesome question. The most basic answer is that light is refracted by particles in the atmosphere and the red end of the spectrum is what is visible. To better understand that you have to have a basic understanding of how light behaves in the air, the atmosphere’s composition, the color of light, wavelengths, and Rayleigh scattering and here is all of the information that you need to understand those things.

The Earth’s atmosphere is one of the main factors in determining what color a sunset is. The atmosphere is made up mostly of gases with a few other molecules thrown in. Since it completely surrounds the Earth it affects what you see in every direction. The most common gasses in our atmosphere are nitrogen(78%) and oxygen(21%). The remaining single percent is made up of trace gasses, like argon, and water vapor and many small solid particles, like dust, soot and ashes, pollen, and salt from the oceans. There may be more water in the air after a rainstorm, or near the ocean. Volcanoes can put large amounts of dust particles high into the atmosphere. Pollution can add different gases or dust and soot.

Next, you have to look at light waves and the color of light. Light is an energy that travels in waves. Light is a wave of vibrating electric and magnetic fields and is a part of the electromagnetic spectrum. Electromagnetic waves travel through space at the speed of light(299,792 km/sec). The energy of the radiation depends on its wavelength and frequency. A wavelength is the distance between the tops of the waves. The frequency is the number of waves that pass by each second. The longer the wavelength of the light, the lower the frequency, and the less energy it contains. Visible light is the part of the electromagnetic spectrum that our eyes can see. Light from a light bulb or the Sun may look white, but it is actually a combination of many colors. Light can be split into its different colors with a prism. A rainbow is a natural prism effect. The colors of the spectrum blend into one another. The colors have different wavelengths, frequencies, and energies. Violet has the shortest wavelength meaning that it has the highest frequency and energy. Red has the longest wavelength and lowest frequency and energy.

In order to put it all together, we have to look at the action of light in the air of our planet. Light moves in a straight line until it is interfered with(gas molecule, dust, or anything else). What happens to that light depends on the wavelength of the light and size of the particle. Dust particles and water droplets are much larger than the wavelength of visible light, so it bounces off in different directions. The reflected light appears white because it still contains all of the same colors, but gas molecules are smaller than the wavelength of visible light. When light bumps into them it acts differently. After light hits a gas molecule some of it may get absorbed. Later, the molecule radiates the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the colors can be absorbed, but the higher frequencies (blues) are absorbed more often than the lower frequencies (reds). This process is called Rayleigh scattering.

Long story short,, the answer to ‘why is the sunset red?’ is: At sunset, light must travel farther through the atmosphere before it gets to you, so more of it is reflected and scattered and the sun appears dimmer. The color of the sun itself appears to change, first to orange and then to red because even more of the short wavelength blues and greens are now scattered and only the longer wavelengths(reds, oranges) are left to be seen.

We have written many articles about the sunset for Universe Today. Here’s an article about sunrise and sunset, and here are some sunset pictures.

If you’d like more info on the Sun, check out NASA’s Solar System Exploration Guide on the Sun, and here’s a link to the SOHO mission homepage, which has the latest images from the Sun.

We’ve also recorded an episode of Astronomy Cast all about the Sun. Listen here, Episode 30: The Sun, Spots and All.


Sunset moonrise what happens in between? - Astronomy

Some of the things that students learn to do include:

Develop and use a model of the Earth-Sun-Moon to describe cyclic patterns lunar phases, eclipses, and seasons. (ESS1-1)

Develop and use a model to describe the role of gravity in motions galaxies and solar system.

Analyze/interpret data to determine scale properties of objects in solar system.

Crosscutting concepts most emphasized: patterns, size and quantity (work on building perspectives with interesting exercises), systems and system models (develop understanding on what scientific models are, and then use them).

Lesson 1 - Modeling the Sun, Earth and Stars (2.5 days). Learn about modeling in science, and use that to conceptualize the sun, Earth, and stars.

Lesson 2 - Earth's Place in the Universe.

Earth is in the Solar System, within a side arm of the Milky Way galaxy (which contains over a 100 billion stars, aka other suns), and there are many billions of galaxies within the Universe. We will build a sense of scale and quantity. Understand Doppler Effect->red shift of stars and galaxies ->conceptualize viewing this expansion in reverse -> Big Bang.

Lesson 3 - Astronomy Instrumentation. We learn about ground and space based instrumentation. The class will use critical thinking to make technology selections given established constraints and objectives. We also make hypothesis while viewing satellite imagery which monitors the Earth, for example, changes in ice coverage at the poles and before->after forest coverage in South America.

Lesson 4 - Solar System Objects. We learn about the various objects in our solar system. We also study gravity the mass and distance, how it holds objects in orbital motion, how it is an essential part of the models we make, how it works with E-S-M motion to create the tides. Computer simulations in class help students see how changes in distance and mass effect gravity.

Lesson 5 - Features in our solar system, working with data, looking at patterns in various attributes of planets.

Lesson 6- Moon Phases and Eclipses-what causes the phases of the moon and different kinds of eclipses.

Lesson 9 - Seasons. This is a some what complex topic. We understand what causes the different seasons in the hemispheres of the Earth. To many student's surprise, it is not caused by the changing distance from the sun to Earth, but the relative tilt of the Earth's axis toward/away from the sun which causes the seasons and varying length of day, especially with latitude. The sun never rises at the north pole during winter solstice! Brrr. Also, the southern hemisphere is always in the opposite season that we are. Low sun angle->less energy per unit area/high sun angle->more energy per unit area.

Here is an overview of how eclipses and tides work:

Solar eclipse: The sun disappears behind the moon during the day when the moon gets between the sun and the Earth. This casts a very small shadow on the Earth. Since the Earth is rotating, you will be under that small shadow for a short period of time before the sun comes back out (and animals like roosters think it is a new day!)

Lunar eclipse: The EARTH gets between the sun and moon. The Earth casts a shadow across the moon! So when you are on the night side of the Earth, you will see a full moon, then the shadow of the Earth move across the moon, then a reddish* moon, the it all happens in reverse as the moon moves out of Earth's shadow, and you end up with a full moon again. All of this happens in the same night!

*The moon looks red because the light of the sun actually goes through Earths atmosphere before hitting the moon, and the scattering of short wave (blue) and longwave (red) light, much like what happens at sunset, hits the moon and makes it appear red!

Tidal Range=the difference between low and high tide, ie, how high the water rises.

The moon pulls twice (2.2 actually) as hard as the sun because it is 400X closer.

"Spring Tide" when the range is the greatest-so, for example, you see a very low tide at 6am with a huge amount of ocean floor and beach showing, then the highest tide at noon, and the water comes up very high on the beach, covering all the tide pools and rocks. That happens when the moon and sun are aligned, like in a new or full moon. The sun helps the moon pull the high tide up, which draws water from elsewhere, where a low tide will happen.

"Neap Tide" is when the range is the least-so, there is not much difference between low and high tide. The water edge does not go far out, nor come very high on the beach during the day. That happens when the moon and sun are perpendicular, like with a half moon. The sun does not help the moon pull the high tide up, so it is not very high, instead, it prevents the low tide from getting very low.

Notice that "Spring" looks a lot like "Strong" tide effect and "Neap" looks a lot like "Weak" tide effect!

This is my favorite video about tides because it is very concise and simple, yet best illustrates how it works, and is quite accurate. (Notice that they call cookies "biscuits" in the UK, -))


8 Answers 8

Well, I'd like to say that you are almost there. The key point of this question is to know that usually illustrations are just showing the relative positions but not with the real ratio.

If the size and distance of the moon is the same as such pictures show, it will much harder to find when it lies at the same side of the sun. Because to see it, the smallest position angle from the sun is $alpha = (R_E+R_M)/D_$ .Then it will vanish more days every month as you say.

But the real situation is like this:

Since the real distance is so far, even the moon is quite close to the sun, people besides the Day Night Terminator can still find it. An estimate can be given in this way: $alpha = (R_E+R_M)/D_ = (6471+3476)/384400 = 0.0259 $ rad. So there a only $ 2 alpha imes 180/pi imes 28/360 = 0.23 $ days we can not see it from the earth. Due to the strong day light, this time can be longer but still within one day.

I stumbled across this question, and while it is an old question and there are some halfway decent answers, I think it deserves a more in-depth response. I completely understand the question, which I think is am excellent question. Trying to understand the phases of the moon is much more difficult than most think.

The short answer of it is that you cannot see a new moon at night. A new moon is not in the sky at night! It rises with the sun and sets with the sun.

The closest you can get to "seeing" a new moon is a "waxing crescent" right after the sun sets, or a "waning crescent" right before the sun rises.

A "waxing crescent" - almost a new moon - is seen only very briefly after sunset. This is because at waxing crescent, the sun rises immediately before the moon rises, and then the sun sets immediately before the moon sets. Therefore, right after the sun sets, and the sun's glare fades in dusk, the very slim crescent (nearly a new moon) becomes visible, and then the moon shortly thereafter sets. and can't be seen for the rest of the night. If the sun's glare weren't so bright during the day, you could see the moon with this slight crescent all day long. But you can't. However, at dusk, when the sun's glare fades over the western horizon, the slim crescent appears! (it doesn't appear because it comes up above the horizon, but only because the sun's brightness fades into the night). But watch the waxing crescent into night, and you will see it quickly set below the western horizon, and it won't be seen again until the following dusk.

A "waning crescent" - almost a new moon - is seen only very briefly before sun rise. This is because at waning crescent, the moon rises immediately before the sun rises, and then the moon sets immediately before the sun sets. As a result, right before sunrise, in early dawn, the slim crescent moon (almost a new moon) rises in the East. It appears as it rises above the Eastern horizon, before the sun rises. However, you can't see it very long, either, because then the sun rises, and the sun's glare is so bright, it overwhelms the slim glimmer of the waning crescent! However, it is still there. and is there in the sky all day long! And finally, the moon sets first over the western horizon in dusk, not to be seen. And then the sun sets. to a moonless night almost all night until right before dawn, when the waning crescent rises to be seen again.

Now then, to more adequately address and answer your question, let's first take this simple demonstration of a girl rotating around in circles while holding a "moon" in front of her with a lamp (sun) in the distance:

From here: http://www.jpl.nasa.gov/education/index.cfm?page=123

In this demonstration (unlike in reality), the girl is always facing the moon as she rotates. She will surely see the various "phases" of the moon in this demonstration, which is a good demonstration for this purpose. However, perceiving where this demonstration fails in comparison to what actually happens with the Earth, Moon, and Sun will help answer your question.

Failure #1: When the girl is facing the lamp with the moon held out in front of her (in Step 1), she will "see" a "new moon". But, when she can see a full moon, she is facing the sun. i.e. it is the day for her.

The reason the demonstration fails is that during a true new moon, when the moon is between the Earth and the sun (during the day), we can't see the moon because the sun is too bright. In other words, although in the demonstration the girl can see her "moon". we can't see ours. For her demonstration to be more accurate, her "moon" would have to be a LOT smaller and the lamp would have to be MUCH brighter. And if the lamp were much brighter. even blindingly bright, then she would not be able to see her small "moon" either.

Although, if the moon passes exactly between the sun and the earth during the day, then we have a total solar eclipse. And during that brief moment, the moon blocks the sun and shades the earth. and we can see the outline of a new moon:

Failure #2 (and the answer to your question): The demonstration fails because the girls is always facing the moon. In reality, this is not so. The Earth rotates, of course. So, for the demonstration to be more accurate, her head would have to be impossibly rotating completely around 360 degrees, continuously. Furthermore, her head would be rotating about 30 times as fast around in circles as her body.

In other words, during the "new moon" phase (Step 1), when her body is facing the lamp (sun) with her arm holding the moon out in the direction of the lamp (sun), imagine her head revolving around 360 degrees.

So, while imagining her head turned around backwards (like in the Exorcism movie), as in during the "night" for the girl. her head would be facing the OPPOSITE direction of the moon AND sun, and the "new moon" would not be visible at night. anymore than the sun. This is because she is no longer facing either one. The "new moon" would not be visible at night, because it is not in her vision of the sky during her night.

Now then. as her head rotated around, and out of the corner of her eye (in the Eastern horizon), she would begin to see the moon and sun at the same time (i.e. during sun and moon rise in the morning), then they would appear together. be in the sky together all day. and set together out of the corner of her eye, again at sunset. In the demonstration, she would be able to see the ball and the lamp, but in reality, the sun is so bright that the moon can't be seen in the sky. even though the new moon is in the sky all day long.

During the waxing and waning crescents (as above), the moon sets just after the sun or rises just before the sun (respectively). Therefore, an almost new moon can be seen briefly before the moon sets or sun rises (respectively).

Finally, understanding a full moon helps shed more light (forgive the pun), as well: Right when the sun is setting, a full moon is rising in the East! The full moon is visible all night long and sets in the West, just as the sun is rising in the East the next morning.

So, a full moon rises early in the night and sets early in the morning. is visible all night long.

Contrarily, a new moon rises early in the morning (with the sun) and sets at night (with the sun). and is not visible at night, at all.

This website is very helpful in its descriptions, as well: http://earthsky.org/moon-phases/new-moon

But again, the best time to almost see a "new moon" (besides a total solar eclipse, of course), is shortly after the new moon. at dusk during a "waxing crescent". or shortly before the new moon. at dawn during a "waning crescent".


Watch the video: Between Sunset and Moonrise by R H Malden (June 2022).