Phases of moon explained using an orrery

As the moon rotates around the earth it travels through phases.
The alignment of the sun, earth, and moon create the phases.
I use an orrery to explain the moon's alignment during,
new moon, waxing crescent, ist quarter, waxing gibbous, full moon, waning gibbous, last quarter, waning crescent, and back to new moon.
The sidereal period is 27.3 and the moon is measured against stars.
The synodic period is 29.5 days and the moon is measured against the sun.

If you enjoyed this video you may enjoy the Earth Science Course with an emphasis on Astronomy.
The course includes 13 videos along with a study guide and an answer key for each guide.
In addition there is a short enrichment activity for each video.

Link to the playlist here.

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Rotation and Revolution of the Earth with an Orrery

Phases of the moon with pictures.

Moon Phases Quiz

[MooMooMath]

If you enjoyed this video you may enjoy the Earth Science Course with an emphasis on Astronomy.
The course includes 13 videos along with a study guide and an answer key for each guide.
In addition there is a short enrichment activity for each video.

Link to the playlist here.


Sorry for the mistake that I didn't catch. At the end of the video, I say the new moon occurs in roughly 27 days. Please let me explain. The sidereal period is 27.3 and the moon is measured against stars and the synodic period is 29.5 days when the moon is measured against the sun. The length of a lunation is 29.530588 days (or 29 days, 12 hours, 44 minutes, and 2.8 seconds) and occurs roughly every 32 days. You may get two new moons in a month. Sorry for any confusion.
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Rotation and Revolution of the Earth

[atexinarabic]

Thanks, you saved me from my daughter questions

[chatsmeow]

Thanks! I know basically how the phases work but it's hard for me to visualize so many things rotating at once so I'm glad someone made a model 😂

[anujverma]

वेरी इंटरेस्टिंग वीडियो अमेजिंग इस तरह अपने सौरमंडल के बारे में ज्ञान दिया इसके लिए धन्यवाद

[justryingmybest]

This is the clearest explanation of the orbit I have seen, thank you!

[evyberm]

I don't know why but I'm cracking up at watching the Earth spin so fast.

[Andreas-nilt]

I think the left/right allignment only applies to the northern hemisphere. The view from the southern hemisphere would be the opposite.

[karmi]

the best video explained about sun, moon and earth rotation. thank you!

[sidjohnson]

Wow, whoever designed the movements of solar system is a god

[jazzpunk]

I could never wrap my head around this...thank you!

[aiwanano]

Humans: “you guys feel something?”

Earth: **spinning at 100mph**

Human2: “nah”

[Niamei_Gonmei]

Easily explained, easily understood. Thank you!

[shendelyndelacruzfelipe]

Thank You for this informative video. Waning Gibbous 3.5 days from full moon (180°/14 days) the illustration at 2:09 should be rotated 225° approx. not 270°. May be typo error

[Hamza-ojnc]

This was such a great video, I honestly had questions and confusions but this was so clear, so thank you!

[paulinacarlisle]

Wonderful! So well-explained..thank you 🌔

[scottyelliott]

So much better than other versions of this explanation, I love how the speeds are represented too.

[Skullswithdronesinside]

Ahhh saved me from having to explain this. So simple and well demonstrated. Thanks!!!

[alexnairn]

Great video - but in one lunar cycle the Earth has travelled around the Sun a bit, so the Moon has to travel slightly More than 360degrees around the earth to get back to New Moon, hence 29.5 days in the lunar cycle

[petrosaircooled]

Thank you for this informative video and your efforts! Please note that Wanning gibbous is shown as 270 degrees instead of 225 degrees.Waning Gibbbous is shown the same as the Last Quarter.

[ZxtxKim-swep]

What a great explanation. 👏 thank you for helping this make sense.