Toy model: linear extrapolation using today’s mean recession rate (varies over time).
Model note: Angular size uses the exact angular diameter formula; at very close distances, angles saturate. For visibility, the diagram's rays/object are visually magnified (the numeric readout is the authoritative value). Units may auto-switch (° / ′ / ″). Internal units = km.
Thumb rule: Your thumb at arm's length covers about 2° of sky.
The Sun and Moon each cover about 0.5° — a quarter of your thumb width!