what+we+want+to+know



 What would happen is the atmosphere had more oxygen?

If the atmosphere had more oxygen, any sort of spark (including lightning) or open flame would ignite uncontrollable fires.

 If the earth's core is molten, why hasn't it exploded? First, only the outer core is molten. The inner core is solid. Second, the core is underneath many thousands of miles of rock. All of this rock exerts great pressure on the core, so much that it could never explode.

 How old is the earth?

The earth is about 4.5 billion years old. Scientists figured this out by studying some of the rocks that are in the ground.

 How thick is the earth's crust?

It depends: under the ocean, the crust could only be 5km thick but land crust is 65km thick. Under all of the crust is the partly molten mantle.

 Why is the Earth able to support life?

The earth is has the right amount of water along with a steady supply of food, both of which are important for life. Also, the atmosphere has the perfect blend of chemicals in the air: nitrogen, oxygen, and others, and it protects us from harmful radiation that is in space. For example, the ozone layer protects us from harmful UV radiation.

What is the greenhouse effect?

The greenhouse effect is like a blanket on a cold winter night. It cause a rise in temperature because certain gases in the atmosphere (water vapor, carbon dioxide, nitrous oxide, and methane, for example) trap energy from the sun. Without these gases, heat would escape back into space and the earth would be frozen, like Mars. If these gases become too thick, however, the earth could get too hot, like Venus.

 How do the motions of the earth affect our daily lives?

All species of life relays on the speed and motion of earth to determine when to sleep and when the weather patterns will change. For every rotation one day passes and the sun is visible to parts of the earth for half a rotation. As one revolution goes by depending how far it is from the sun changes the weather. This is all essential to all the species if Earth so they can survive.  What would an alien need to know about the earth?

An alien would need to know 6 categories of information: atmosphere, appearance, climate/weather, surface/composition, water, and life forms. It would also need to know about any possible hazards here.  Before humans what was the dominant species?

Before people, dinosaurs ruled and roamed the earth. The planet only had animal species nothing like humans then it was all animals.  What wiped the dinosaurs out?

65 million years ago, an asteroid hit the earth, creating a large crater near the Gulf of Mexico and wiping out most of the large animals on the earth. 