Will a comet hit the earth?
We don't know of any at the present time. The asteroid Apophis 99942, when it was discovered was thought to have a possibility of impact in 2029. An impact alert was issued for 2029. When further observations showed it would not hit Earth, the alert was canceled. If it passes through a narrow gravitational keyhole on its 2029 pass, it has a possibility of impact in 2036. It's impact risk for 2036 is currently at 1 in 45,000. It will be monitored closely to determine whether it is drawn into an orbit that would make a 2036 impact more likely and mitigation methods are being investigated in case they are needed. Apophis, at 330 meters long, is too small to have widespread effects if we did have impact. It would cause regional destruction, but is not large enough to result in an impact winter or a threat to life on more than a regional scale. The table at this link shows all known impact risks for the next 100 years.
What would the world be like had the Earth not been hit by the comet that wiped out the dinosaurs?
I visited a dinosaur museum in Dorset and they had a model of what a 'human' might have looked like if the dinosaurs had not been wiped out. Looked a bit like an alien, named Dinosarid, it would have been tree living, like monkeys and probably not the highest in the food chain! (big black eyes, bulbous baldie headed thing). It had scaley green skin. All I can say is thank god that meteor hit!!!!!!
Will haley's comets will ever hit earth?
There is only one "Halley's comet", not comets. I don't know of any comets named "Haley". The path of Halley's comet does not intersect the Earth's orbit, so a collision is impossible for at least a few billion years. The path does come close the to the orbit of Venus; perhaps a collision is possible there. It is impossible to predict the exact orbit of this comet for more than a few 1000 years into the future, so we have to use probabilities. A simple calculation shows that even if the orbits of the comet and Venus crossed each other (they come close, but not that close), it would be about 2 million years before a collision. What will actually happen to comet Halley is that it will pass close to Jupiter, sometime in the next 10 million years, and be gravitationally kicked out the solar system forever.
If a 10-mile-wide comet hits the earth, how will this likely affect the history of life?
a. A mass extinction will occur followed by lots of evolutionary change by descendants of the survivors. b.A slow climate warming and drying will begin decreasing the biological diversity on earth. c. Most species will become extinct and the rest will remain more or less unchanged. d. Continental drift will be reversed and all the continents will slowly be pushed together again. e. All life will end.
Can comet become a satellite of Earth?
An incoming body can become a satellite of the Earth if there is a mechanism for it to dump excess momentum and be captured in the Earth's gravitional field. This can occur by grazing incidence intersection with the atmosphere (aerobraking), framentation (fragment is energetically ejected, remainder orbits), or collision. Comets are icy dirtballs with little structural strength. If they get close to the Earth they can be within their Roche limit, and disintegrate, http://en.wikipedia.org/wiki/Roche_limit http://scienceworld.wolfram.com/physics/... Look up Tunguska.