An artist rendering of the Earth with rings. - Photo courtesy of Kevin M. Gill (CC BY 2.0)
DUBBED the "Jewel of the Solar System", Saturn with its beautiful rings is truly a glorious sight to behold. Made up of ice, dust and floating rock, the rings are actually a debris field that has been gravitationally locked to orbit Saturn. It is however, not the only planet to have rings, all of the gas giants boasts rings in one way or another and it's even predicted that Mars will eventually get its own set of rings in about a million years when its moon Phobos eventually disintegrates in its atmosphere.
Some say the Earth used to have its own rings, is this true?
Verdict:
MOST LIKELY TRUE
Yes, the Earth most likely boasted its own rings far in its distant past and this wals all thanks to the Moon, or at least its creation.
There are three ways a planet can develop a moon. The first, Co-formation Theory, being that it forms at the same time as its parent planet from the protoplanetary disk - the matter orbiting our early Sun - this is how scientists believe most of the larger moons orbiting Jupiter were created.
The second, Capture Theory, being that the moon forms elsewhere in the solar system and then is captured by its parent planet's gravity well - which is how Mars got its two moons Phobos and Deimos.
The third theory, which is also the most popular theory for how our moon was formed, was that another protoplanet impacts its parent planet, shattering both and then the various bits congeal back into being the host planet and new moon.
Why the third option is the current leading theory for how we got our moon is that the elements found on both the Earth and moon are similar enough to suggest co-formation but the fingerprints of a third protoplanet can be found on both.
This hypothetical third planet, which has been named Theia by scientists, is said to have struck Earth 4.5 billion years ago and when it hit it not only ejected enough material to form the moon, but a hypothetical ring as well.
How long this ring stayed in orbit around the Earth is uncertain. It could have all been sucked up into the new moon, or parts of it could have stayed on for a few million years before either falling on the Earth as meteorites, pulled into the moon or ejected back into space.
As a side note, technically the Earth has a ring around itself right now but unlike Saturn's ring of ice and dust, ours is made up of satellites and space junk.
References:
1. https://www.sciencefocus.com/space/why-doesnt-earth-have-rings
2. https://www.universetoday.com/14484/does-earth-have-rings/
3. https://www.science.org/content/article/remains-impact-created-moon-may-lie-deep-within-earth
4. https://news.uchicago.edu/explainer/formation-earth-and-moon-explained
6. https://www.skyatnightmagazine.com/astrophotography/planets/jupiter-galilean-moons
