Gusev
Key facts
- Country
- Russia
- Diameter
- 3 km
- Age
- about 49 million years
- Location
- 48.43° N, 40.53° E
Nothing: the small crater is buried beneath the steppe of Rostov Oblast, southern Russia, a short distance from the larger Kamensk crater.
Gusev is a small buried impact crater about 3 km across in Rostov Oblast, southern Russia. It lies a few kilometres from the much larger Kamensk crater, and the two appear to have formed at the same time.
What it hit. Like Kamensk, Gusev formed when an impactor fell into a shallow sea about 49 million years ago, in the Early Eocene, and struck Carboniferous sedimentary rocks beneath the sea floor. The sea then refilled the crater.
Proof of impact. Drilling found breccia and melt rock with shock features in minerals, confirming an impact.
Age. Dating of impact rocks gives an age of about 49 million years, the same as Kamensk within the uncertainty of the measurements.
A double impact. Because Gusev and Kamensk are so close and of the same age, scientists think they were probably made by a binary asteroid, a large body with a small moon. Telescope observations show that roughly one in six larger near-Earth asteroids has a moon, so double craters should not be rare on Earth.
Why it matters. Gusev and Kamensk are among the clearest examples of a double crater on Earth. The impactor is unknown.
Did you know?
Gusev and Kamensk are probably a double crater made by an asteroid and its moon.
Both formed in a shallow sea about 49 million years ago.
Roughly one in six near-Earth asteroids has a moon.