That has already been closely watched and carefully measured, by
many skilled and dedicated astronomers. It takes 687 earth days.
The earth would revolve around the sun.
It would get longer, since the amount of time the Earth takes to orbit the Sun is essentially the definition of a year.
Mainly, to revolve around the Earth in 15 days, the Moon would have to be closer (you can calculate the ratio using Kepler's Third Law). This would make the tides stronger.
They would think that all of the cosmic bodies revolve around something other than the sun.
Mars does not revolve around any planets, it is a planet in its own right. If it did, it would be called a moon. It orbits the sun directly.
If the earth did not revolve around the sun, there would not be any seasons. The problem is that if the earth did not revolve around the sun, that is, if it came to a stop in its orbit, the sun's gravity (with just the tiniest help from the earth's) would pull the earth into the sun.
it takes mercury 88 earth days to revolve around the sun
earth wouldn't have different seasons
The earth would revolve around the sun.
Then that would be the length of the year.
No. As Earth rotates, they seem to. It would be like if you turn around on one spot, everything seems to be moving around you.
yes
BOTH!, because it revolves around the sun (goes are around the sun) and rotates (turns around) to define if it is day or night if the earth didn't rotate we would be stuck with either day or night all the time and if it didn't revolve we would be stuck with the same season.
every planet has a certain amount of days to reach a year. So just like earth, other planets would have to revolve around the earth. (this was an easy question to not already be answered)
the proportion of the earth and the moon would be much different, and the moon would then revolve on its own around the sun.
Circle when it is used as a verb like, The Earth circles the sun. A similar word to orbit would be revolve, as in 'the earth orbits around the Sun' and 'the earth revolves around the sun'.
If it took 398 days for the earth to revolve around the sun, it would be 398! It takes 365.25 days for the earth to orbit the sun.