Spore begins with a comet impact on earth.

Such an increase could be caused by a large asteroid or comet impact, a large supervolcanic eruption, or extensive global warming.

It has been debated whether their extinction was caused by human overkill, climate change, or possibly even the aftermath of a comet impact.

The drill was intended to give astronomers and other experts in asteroid and comet impact studies practice in responding to a hypothetical immanent impact with global consequences.

That the lunar craters were confirmed to be the result of meteor and comet impacts and not volcanic activity enhanced our understanding of conditions in the early solar system.

In addition, the rotation of the comet nucleus will also change the relative position of the lander and the orbiter.

The volume scattering coefficient measures the homogeneity of the interior of the comet nucleus.

Solar heating causes gases to be released from the comet nucleus, which also carry away dust grains.

It has a well determined orbit and has a comet nucleus 26 km in diameter.

This investigation would provide the first look at the changes to a comet nucleus produced after a close approach to the sun.

The comet orbits the sun in an elliptical orbit with a period of 5.96 years.

On that day, the comet orbits to the earth.

For considerable time he was particularly concerned with comets, and published a catalog of comet orbits.