why do we have sometimes a full moon during daylight hours?

Question

during full moon, the moon is 100% illuminated or close to 100% and can be see at night. Lunar phase tables give you the day/time (UT) . some of these times (during the year) occur during the day (not night). Even if you substract your local time from UTM, you still may get day hours instead of night hours. I thought full moon only occur at night.

none of the above! I found an intelligent answer on the internet (based on sideral and synodic periods).
Thanks anyway for some of your answers. Although two of them were too rude for a honest question.

Answer 1

If the moon is truly full, you can't see it during daytime. However, a couple of days before or after, the moon looks very close to full, and will be visible shortly before sunrise or shortly after sunset.

The time of truly full moon, however, is exactly 1 instant in time - 1 second later or earlier, and it's 99.9999% full. This is the time listed on the tables.

Those times may occur while the moon not currently visible to you, but is visible to someone on the other side of the Earth.

Answer 2

I won't bother talking about it, so I'll quote the Bad Astonomer right here.

"Quick: what's the second brightest natural object in the sky?

The brightest is obviously the Sun. The second brightest is the Moon. The Moon is so bright that it casts clear shadows at night, you can read by it, and even through a modest telescope it can make your eyes water. So why do so many people think you can't see it during the day?

Perhaps they think it is washed out by the Sun. It isn't; if it's up and more than about first quarter it can be seen without any problem if you know where to look. Perhaps they think that it literally is only up during the night, and not during the day. This cannot be true; it orbits the Earth, making a complete circle once a month or so (the word 'month' actually comes from 'Moon'). It orbits in roughly the same path that the Sun follows on the sky, so sometimes it must be between the Earth and Sun, putting it up in the sky at the same time as the Sun, that is, during the day.

I think the answer is more subtle and more telling of how many people live their lives: they simply don't notice what goes on around them. The Moon is easy to see during the day, if people would simply look up! How many times have I seen beautiful rainbows and breathtaking halos around the Sun with multicolor sundogs and found that no one else has noticed? Most non-astronomers I talk to are shocked to find that they can see planets and man-made satellites with their unaided eyes on almost any clear night. But all they need to do is look up and see. "

Answer 3

Starting with the full moon - A day or two before the "full moon" you will see the moon rise just before sunset. At full moon it will rise as the sun sets, and of course after the sun sets as the time goes on. Each night after, notice how the light on the moon shrinks from full to last quarter and then to nothing (a 2 week time period).
Also during this time you will notice the moon "traveling" closer to the sun.
Two weeks from full moon (day may vary) look for the sliver of the moon just before sunset.
As the moon moves into NEW moon and you cannot see at all, watch for it to become noticable as a sliver in the other direction as the sun sets. Follow the light on the moon as it expands to first quarter and then to full. So you can actually see the moon and the sun at the same time virtually most of the month.

Answer 4

We all know that the Moon is the back side of the Sun. So how can you see a moon in the sky at the same time as the Sun? Easy, the back side of the Sun (the Moon) is reflected off the firmament (where God keeps the water that flooded Earth -See Noah's Flood) and this reflection is then re-reflected off the other side of the firmament, which surrounds the Earth. This double reflection is necessary, or the Moon would appear as a mirror reflection instead and this would defy logic. Does this clear up the question for you?

Answer 5

It actually is possible, but only at sunset or sunrise. The earth's atmosphere acts somewhat like a glass fiber in that even after the sun has passed below the horizon, we still see it for a little bit longer. Likewise, we actually see the moon rise before it has cleared the horizon. The time period is very short and the sun and the moon will be on opposite horizons, but it is possible.
It is also possible to see both the sun and a full moon at +/- 67 degrees latitude on the summer solstice, (assuming the moon is full on that day) At that point in time, the sun does not set and if you are on a high point (building top or in a plane) you will be able to see the sun and moon on opposite horizons.

Answer 6

I think it is because the Moon's orbit is tilted a few degrees to the plane of the Earth's orbit, called the ecliptic, so the full Moon usually isn't exactly opposite the Sun in the sky, It is slightly above or below the ecliptic. When it is really, exactly opposite the Sun on the celestial sphere, which means exactly on the ecliptic, then there is a lunar eclipse. In fact, that is why it is called the ecliptic. The ecliptic is the line where eclipses can occur.

Answer 7

Full moon does only occur at night. Those other times were when you were dropping acid and mistook a frisbee for the moon. What's messing with your head is the fact that the moon looks the same from all around the planet - so it becomes 'full' at a certain universal time, even if you cannot see it. E.g., at a certain time of month, the moon is defined as 'full' - then, throughout the day, even when it is hidden, it should be considered a 'full moon'. But it's only visible at night.

Answer 8

In summer, when daylight is considerably longer than 12 hours, it is possible to see the full moon during daylight.

Of, course, as a previous repsondant points out, you are getting technical here. You are talking about the exact astronomical full moon when the moon is exactly 180 deg opposite the sun.

But as far as our eyes can discern, the moon is full half day either side of that point, so we can see a full moon during daylight (only just).

Answer 9

because sometimes the moon is still in a position to reflect from the sun when the sun is still out a taste.

Answer 10

you will see the moon even against the blue backdrop of the sunlight hours sky, via fact the moon is amazingly vivid! that is not everywhere close to as vivid via fact the solar of direction. after all, it in hassle-free terms shines by ability of reflecting mild from the solar besides - and not that nicely. in spite of the undeniable fact that that's brighter than the different organic merchandise interior the sky.