a-monster-4
Explanation
The Joke
A child in bed calls out to their mother: "Mom! There's a monster under my bed!" The mother asks, "Where?" The child cheerfully responds: "About 12,700 kilometers down, depending on your choice of angle."
The child is not talking about a monster hiding in the usual sense. Instead, the child is pointing out that directly beneath their bed -- if you go straight through the Earth -- there is someone (or something) on the other side of the planet. The distance of approximately 12,700 kilometers is roughly the diameter of the Earth, meaning the "monster" is a person on the opposite side of the globe.
The bottom caption delivers the final punchline: "If you live in Australia, there is always an American under your bed." This makes the geographical joke explicit -- due to Australia and the United States being roughly antipodal (on opposite sides of the Earth), an Australian child could technically claim there is an American "under" their bed.
The Humor
The humor lies in the child taking the concept of "under my bed" to its most literal and extreme geographic interpretation. Instead of the typical childhood fear of a monster lurking in the shadows beneath the bed frame, the child applies a scientific understanding of the Earth's geometry. The punchline about Australians and Americans being on opposite sides of the globe adds a playful nationalistic element, implying that Americans are the "monsters" under Australian beds (or vice versa). The child's cheerful delivery contrasts with the mother's concerned expression, enhancing the comedic effect.
References
The Earth's diameter is approximately 12,742 kilometers, making the child's estimate of 12,700 kilometers quite accurate. The concept of antipodal points -- locations diametrically opposite each other on the Earth's surface -- is the geographic principle at play. While the United States and Australia are not perfectly antipodal (the true antipode of much of Australia falls in the Atlantic Ocean), they are roughly on opposite sides of the globe, making the joke work as an approximation.