There would be no seasons.
The seasons would switch to six months later (earlier).
There would be no four seasons if the earths axis was not tilted.
very very cold
Mainly, there would be no seasons.
It is tilted (23.5 degrees).
If the earth was not tilted at an angle of 23.5 degrees, there would not be the different seasons.
without the tilted axis the whole planet would be impossible to live on since this angle is a state of equilibrium
it would probably be the same nights and days
The seasonal variations would be different.
It would receive more direct Sun in the summer.
the seasons will change!!
Assuming the observer is in the North, then the southern hemisphere would be tilted towards the sun during the Winter Solstice in December. However, for observers in the Southern Hemisphere, the Winter Solstice would occur in June, and the northern hemisphere would be tilted towards the sun.