Transcript: When we look at the lists of the brightest stars in the sky and the nearest stars to the Sun we see that there are almost no stars in common. In fact, among the first few dozen stars in each list only Sirius is in common. Why are the lists so different? When we look at the brightest stars in the sky we are looking preferentially at high luminosity stars. Hertzsprung called these the whales among the fishes. So when we search for the apparent brightness of a star we preferentially see the most luminous stars because we can see them to the largest distance, and so we sample a larger volume for them than for low luminosity stars. Thus samples of stars limited by apparent brightness will over represent the whales, or the more massive stars, relative to the fishes, the much more abundant low mass stars.