31 Oct '15 17:05>
Originally posted by JerryH
You don't define the earth as the third planet from the sun in our solar system? A planet is not now defined as being spherical? Please give me your definition of the earth.
You don't define the earth as the third planet from the sun in our solar system?
No, that' s an observation and not a definition.
If [when] Mercury's orbit destabilises and it flies out the solar system [or into the Sun] the
Earth wont stop being the Earth.
If we decide to extend the life span of the Earth by moving it farther out from the Sun as the
Sun ages and expands and we swap places with Mars it wont stop being the Earth.
A planet is not now defined as being spherical?
Nope.
First no planet [we know of] IS spherical. The Earth is an irregular oblate spheroid.
And again, this is an observation about the nature of our planet, and not a definition.
Planet originally meant 'wandering star' and was used to describe the bright 'stars' that moved across
the sky. It was only much later that we discovered that they ware not just points of light, and were
in fact huge lumps of rock/gas floating in space and that we were also on a planet of our own.