During Diwali, candles are lit all around the country in celebration. How many candles would need to be lit in a 40 x 40 meter s
quare area in order for an astronaut in the International Space Station (400 kilometers above ground) to see a spot of light which is as bright as a single candle at 100 meters? Any answer within 10% of the correct answer is accepted. Ignore atmospheric effects for simplicity.