Christmas is celebrated in summer in which country?

Concept: Earth's axis is tilted at about 23.5° away from the perpendicular to its orbital plane (equivalently, about 66.5° to the orbital plane itself), so the Northern and Southern Hemispheres always experience opposite seasons. When it is winter in the Northern Hemisphere, it is summer in the Southern Hemisphere, and vice versa.

Application: 25 December falls in the Northern Hemisphere's winter season and in the Southern Hemisphere's summer season. Checking each country's hemisphere and matching season identifies which one has a summer Christmas:

• Japan lies in the Northern Hemisphere (East Asia), so 25 December falls during its winter.

• India lies in the Northern Hemisphere (South Asia), so 25 December falls during its winter.

• America (the United States) lies in the Northern Hemisphere, so 25 December falls during its winter.

• Australia lies in the Southern Hemisphere, where the seasons run opposite to the Northern Hemisphere, so 25 December falls during its summer.

Cross-check: Australia's Christmas is well documented as a summer holiday there, often marked with beach visits and outdoor barbecues rather than snow, which is consistent with its Southern Hemisphere location. Hence, Australia is the country where Christmas is celebrated in summer.