Gibbous and crescent
More than half, or less than half.
Between half and full
The Moon is bigger than a half circle but not yet full. Another night it is a thin sliver.
Are these two shapes the same phase?
What this lesson covers
The idea
When more than half of the Moon's illuminated portion is seen from Earth it is the gibbous phase; when less than half is seen it is the crescent phase.
Between half and full
The Moon is bigger than a half circle but not yet full. Another night it is a thin sliver.
Are these two shapes the same phase?
- No, they have different names
- Yes, both are full Moon
- Yes, both are new Moon
Find them
Find a crescent and a gibbous Moon.
More or less than half
When we can see more than half of the lit portion, the phase is called gibbous. When we can see less than half of it, the phase is called crescent.
Gibbous: more than half of the lit part is seen. Crescent: less than half is seen.
- Phase | How much of the lit part we see
- Crescent | Less than half
- Half circle | Half
- Gibbous | More than half
Notes
Crescent: less than half. Gibbous: more than half.
Check yourself
The phase in which more than half of the lit part is seen is …
The phase in which less than half of the lit part is seen is …
A thin sliver of the Moon is a …
The Moon looks bigger than a half circle but not full. It is …
- crescent. In a crescent, less than half is seen.
- gibbous — correct. Yes!
- new. On new Moon none is seen.
- gibbous. In a gibbous phase, more than half is seen.
- full. On full Moon, the whole lit half is seen.
- crescent — correct. Yes!
- crescent — correct. Yes!
- gibbous. A gibbous Moon is more than half.
- full Moon. A full Moon is a full circle.
- crescent. A crescent is less than half.
- gibbous — correct. Yes!
- new. On new Moon it is not visible.