The second largest crater in the world was formed by the impact of a comet according to a 2014 study by researchers in Canada and Ireland. Colliding with Earth almost 1.85 billion years ago, the estimated diameter of the crater is 81 miles (130 km).
How big is a bacteria compared to a human cell? The size of a typical bacterial cell is 0.5-5.0 micrometers, a average human cell is 10 micrometers.8 people found this useful.Edit.he consensus among biologists is that only 5 to 10% of the trillions of cells in our bodies are human. The rest are alien cells: yeast, fungi, bacteria, viruses.
Bacteria are about the simplest cells that exist today. A bacteria is a single, self-contained, living cell. An Escherichia coli bacteria (or E. coli bacteria) is typical -- it is about one-hundredth the size of a human cell (maybe a micron long and one-tenth of a micron wide), so it is invisible without a microscope.