Answer: No they don't occur at the same time
Summertime in the northern hemisphere happens when it is winter in the southern hemisphere, and vice versa.
The tilt of the earth causes the seasons. The northern hemisphere's summertime means that the northern part of the earth gets more sunlight compared to the southern half, so the southern half experiences winter.
With the tilt held at the same angle, the earth revolves to another point in space, so that the northern hemisphere receives less sunlight and the southern hemisphere gets more. So the seasons swap.
Answer: Winter
Explanation: The tilt of the Earth determines the seasons for the Northern and Southern Hemisphere. When the Northern Hemisphere tilts toward the Sun, it experiences summer. At the same time, the Southern Hemisphere tilts away from the Sun. It experiences winter.
