A waxing crescent moon – sometimes called a young moon – is always seen in the west after sunset.
At this moon phase, the Earth, moon and sun are located nearly on a line in space. If they were more precisely on a line, as they are at new moon, we wouldn’t see the moon. The moon would travel across the sky during the day, lost in the sun’s glare.
But a waxing crescent moon is far enough away from that Earth-sun line to be visible near the sun’s glare – that is, in the west after sunset. This moon phase is seen one day to several days after new moon. On these days, the moon rises one hour to several hours behind the sun and follows the sun across the sky during the day. When the sun sets, and the sky darkens, the moon pops into view in the western sky.
Note that a crescent moon has nothing to do with Earth’s shadow on the moon. The only time Earth’s shadow can fall on the moon is at full moon, during a lunar eclipse. There is a shadow on a crescent moon, but it’s the moon’s own shadow. Night on the moon happens on the part of the moon submerged in the moon’s own shadow. Likewise, night on Earth happens on the part of Earth submerged in Earth’s own shadow.
Because the waxing crescent moon is nearly on a line with the Earth and sun, its illuminated hemisphere – or day side – is facing mostly away from us. We see only a slender fraction of the day side: a crescent moon. Each evening, because the moon is moving eastward in orbit around Earth, the moon appears farther from the sunset glare. It is moving farther from the Earth-sun line in space. Each evening, as the moon’s orbital motion carries it away from the Earth-sun line, we see more of the moon’s day side. Thus the crescent in the west after sunset appears to wax, or grow fatter each evening.
Photo credit: Peter Rodney Breaux
You sometimes see a pale glow on the darkened portion (night side) of a crescent moon. This glow is due to light reflected from Earth’s day side. It’s called earthshine.
As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.
Understanding Moon Phases
Waxing Crescent
First Quarter
Waxing Gibbous
Full Moon
Waning Gibbous
Last Quarter
Waning Crescent
New Moon
this is good website! but add more
IS A GREAT SOURCE OF INFORMATION. I AM RECOMMENDING IT TO A SIX GRADE CLASS FOR STUDIES ON THE MOON PHASES.
Thanks Patrick!
Good luch with that samuel
thxxxxxxxx
Hi. cool website. Yeah just what I was thinking. Well I gotta go,. yup. bye.
Hi
great website!
When will the waxing moon be in Taurus,scorpio,Cancer,Pisces and capricorn in Brisbane qld 2010.Thankyou please email the answer to arabiansummers@yahoo.com.au
Hmm… interesting… ;)
Kool i cant wait till May 15,2010!!!! there is going to be a waxing moon!! woohoo!!!!! :) :) :) :) :) :) :) :) :) :) :)
this website is really good but it needs just a littel more info!!!
Wow.. i think ive seen something like this before.. it is truely beautiful. I love space! and talking about the moon, i think its pretty amazing how everynight we can see the huge craters in our moon from the ground. I guess theres probably only few of us who think that way.. but it still is truely amazing to me
Me too I wanna know when will the waxing moon be in Scorpio this year. WAxing cresent moon would really be a nice view.
Whoa
This is so cool this totally rocks
WHEN IS THE NEXT WAXING MOON?
23-2-2011
that is awesome
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[...] waxing crescent moon – sometimes called a young moon – is always seen in the west after [...]
[...] waxing crescent moon until right around sunset? Here’s the explanation why, from EarthSky.org: At [waxing crescent], the Earth, moon and sun are located nearly on a line in space. … But a [...]
Could some one make me understanding the rules of new moon rise after ending old. On every month ? Thanks in advance. Maqbool Hussain
Maqbool, it would be hard to answer that question in words – much easier with an illustration. That’s because the conditions of seeing young moons – crescents in the west after sunset – vary throughout the year as Earth orbits the sun and the moon orbits Earth.
In fall, for example, the crescent moon will appear to one side of the sunset – and in spring it will appear directly above the sunset. So a young moon is easier to spot in spring than in fall. You can see a springtime young moon a day or two sooner than you can see the young moon in fall.
There are subtle variations for every month of the year. I’m afraid I don’t know of an online illustration of this phenomenon. I believe there is an illustration in a book called Astronomical Companion by Guy Ottewell. You can also learn by observing throughout the year. Stand in one spot, and draw the location of the earliest young moon you see with respect to the sunset – month after month – for a year. You will see the differences.
I hope this is helpful!
Deborah
What a cool website, actually..I think it is boring
[...] to EarthSky: The waxing crescent moon and the sky’s brightest planet, Venus, shine low in the southwest at dusk on December 26, 2011. [...]
[...] See a picture of a waxing crescent moon. [...]
Well, I Keep Missing Lunar And Solar Eclipses.
this is wönderful information .. Wonderful!!.. Can i also know why its regarded as the oldest phase of the moon.
Kelvin,
A new moon starts the lunar cycle, so a waxing crescent moon is considered to be a young moon because it is first seen in the western evening sky after new moon. A waning crescent moon is regarded as an old moon because it’s last seen in the eastern morning sky before new moon. For a write-up on the new moon, go to http://earthsky.org/moon-phases/new-moon.
Bruce
[...] the meantime, tonight, you can also use the waxing crescent moon to find a famous pair of stars this Friday, April 27. They are Castor and Pollux, the beacon lights [...]
i love this website it works good for my project :)