Question

what would happen if the earths axis was really perpendicular to the plane of the earth orbit

Answer 1

In it's orbit around the sun, when the Earth is tilted toward the sun it is summer in the Northern Hemisphere and when the Earth is tilted away from the sun it is winter in the Northern Hemisphere. ... Well, if the Earth was not tilted, the plane of the Earth's poles would always be perpendicular to the sun