The Palomar planet-crossing asteroid survey, 1973-1978

Photographic coverage of about 80,000 deg² of sky with the Palomar 46-cm Schmidt camera has yielded 12 new planet-crossing asteroids as well as many objects in the main asteroid belt. The estimated population of planet-crossing asteroids includes ∼100 Atens, 700 ± 300 Apollos, 1000–2000 Amors, 10,000 ± 5000 Mars crossers, and ∼5000 Mars grazers.