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Ask an Astronomer

the moon

THe Earth and Moon are tidally locked, right? So does that mean, if the Earth were a sun, that one side of the moon would NEVER face the sun? Thanks!!!

November 21, 2025

Yes, you have it right!  As the Moon is tidally locked to Earth, only one side of the Moon would faced the Earth, while the other does not However, it is possible that...

TagsTags:
The Moon
Tidal Locking
Tides
CategoriesCategories:
The Earth
The Moon

Solar eclipses are not perfect with the moon’s size being slightly smaller and getting smaller as the moon moves further away from earth. Was there ever a time in history that it was perfect, with the moon’s apparent size being the exact same as the sun? If so, when?

January 17, 2025

The Moon is indeed slowly getting further and further away from Earth  But that's not the whole story  The Moon's orbit is slightly oval, so its distance is constantly changing...

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Admin Owl
Eclipses
The Moon
CategoriesCategories:
Lunar & Solar Eclipses
Our Solar System
Stargazing
The Earth
The Moon
The Sun

Can we prove that the Moon isn’t hollow?

June 25, 2024

The gravitational field of the Moon would be unaffected by the radial distribution of mass within the Moon if the lunar mass were spherically symmetric (ie, density of the moon...

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Admin Madz
Legacy
The Moon
CategoriesCategories:
Intermediate
Our Solar System

Does the Moon rotate? Are there other moons that always keep one face toward their planet?

March 5, 2024

Be a little careful the Moon does rotate If you stood on the Moon, the stars would rise and set, just like they do on Earth, except that a lunar day is a month long, the same...

TagsTags:
Admin Madz
Legacy
The Moon
Tidal Locking
Tides
CategoriesCategories:
Intermediate
Observational Astronomy
Our Solar System