The large lunar craters Hertzsprung lies on the equator of the moon back to the east of its center. He is one of the largest ring structures on the moon.
- Selenografische coordinates 11 to -9 °, center of the crater 128 ° West
- Diameter of about 500 km
- Named after the Danish astronomer Ejnar Hertzsprung ( 1873-1967 ).
The large crater has the shape of a huge double ring, the inner ring has been 250 km in diameter, circular and has a strong negative gravity anomaly on (negative Mascon ) that changes all around into positive ones.
Inside the formation are numerous smaller craters, the largest of which has 50 km in diameter. The inner ring also has two short rows crater, the southern outer ring two times using 10 single craters, which may be secondary crater of a larger impact.
Exactly the same form of the double ring is also found in the south-west lying giant craters Apollo and Korolev. Likewise, the three major structures of the moon back of similarities in the gravity picture ( also weaker on Mare Orientale ), which points to related histories.