What are the two factors that affect the size of an impact crater?

The factors affecting the appearance of impact craters and ejecta are the size and velocity of the impactor, and the geology of the target surface.

How does angle of impact affect crater size?

Effect of the impact angle on crater size: Crater size decreases proportional to the sinus of the impact angle α . This decrease is more pronounced for stronger materials. Depending on which of both processes dominates the other, the resulting crater is either circular or elliptic.

What are 4 or more factors that affect the appearance of impact craters?

The size and shape of a crater depend on several factors:

• the mass of the impacting object;
• the density of the impacting object;
• the velocity of the impacting object; and.
• the geology (type of rock) of the surface the object strikes.

How do impact craters change over time?

Impact craters go through an aging process. They start out new and pristine, but they gradually degrade. Newly made simple craters are fresh, with sharply defined rims, and deep bowl shaped depressions. The craters gradually degrade until they are “soft” looking, and no longer have deep bowl shapes.

Why are impact craters important?

Impact craters allow scientists to study a planet’s geological history—even when the records are buried beneath the surface. During an impact, buried material is ejected while outward pressure pushes the rock at the crater’s edge upward, forming a rim.

How big can impact craters be?

These range in diameter from a few tens of meters up to about 300 km (190 mi), and they range in age from recent times (e.g. the Sikhote-Alin craters in Russia whose creation was witnessed in 1947) to more than two billion years, though most are less than 500 million years old because geological processes tend to …

How do you identify impact craters?

Identifying impact craters

1. A layer of shattered or “brecciated” rock under the floor of the crater.
2. Shatter cones, which are chevron-shaped impressions in rocks.
3. High-temperature rock types, including laminated and welded blocks of sand, spherulites and tektites, or glassy spatters of molten rock.

What happens to meteorite craters over time?

Impact craters go through an aging process. They start out new and pristine, but they gradually degrade. This is because impact events are happening all the time, and the craters they create are eventually bashed up by other impact events.

Why do most craters form in a round shape?

Because the final crater may be as much as 100 times greater than the diameter of the impactor, this requires an impact at an angle of no more than a few degrees from horizontal. For this reason, the vast majority of impacts produce round or nearly round craters, just as is observed.

Can a meteor create a circular crater on the Moon?

Not really. If the meteor hits the moon at a very shallow angle and just grazes the surface, the crater may not be circular. In this case, the kinetic energy would be deposited over a larger area, as opposed to being concentrated at a single point.

Why do most impactors have a circular shape?

The circular shape is due to material flying out in all directions as a result of the explosion upon impact, not a result of the impactor having a circular shape (almost no impactors are spherical). Craters are the most common surface features on many solid planets and moons—Mercury and our Moon are covered with craters.

What happens when an impactor hits a crater?

If an impactor is large enough, some of the material pushed toward the edges of the crater will slump back toward the center and the rock beneath the crater will rebound, or push back up, creating a central peak in the crater. The edges of these larger craters also may slump, creating terraces that step down into the crater.