Is Earth in Danger from the Incoming Comet?

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    Comet Earth
AI Thread Summary
A comet is currently 100 Earth radii away and approaching Earth at 15,000 km/h, with a trajectory slightly off the direct line between the two. The discussion revolves around whether the comet will collide with Earth or enter the geostationary zone, which is at 6.62 Earth radii. Participants suggest using Kepler's second law of planetary motion to analyze the comet's potential impact and necessary speed for intersection. The key questions focus on determining the comet's energy and trajectory to assess the likelihood of a collision. Understanding these dynamics is crucial for evaluating any potential danger to Earth or its satellites.
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Homework Statement


A comet is observed in a distance of 100 Earth -radius away from the Earth. It is approaching with a speed of 15000 km/h in a direction only 50 off the line connection the two objects.
Earth mass 5.97*1024 kg
Earth radius 6.378*106 m
Gravity constant 6.6726*10-11 Nm2/kg2
(The geostationary zone is an orbit with radius of 6.62 Earth –radius, and is packed with communication satellites orbiting the Earth.)

Homework Equations


Will the comet hit the Earth, and if so – when ?
Will the comet hit the geostationary zone, and if so – when ?

The Attempt at a Solution


Don't know what to do?
 
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Troodon said:

Homework Statement


A comet is observed in a distance of 100 Earth -radius away from the Earth. It is approaching with a speed of 15000 km/h in a direction only 50 off the line connection the two objects.
Earth mass 5.97*1024 kg
Earth radius 6.378*106 m
Gravity constant 6.6726*10-11 Nm2/kg2
(The geostationary zone is an orbit with radius of 6.62 Earth –radius, and is packed with communication satellites orbiting the Earth.)

Homework Equations


Will the comet hit the Earth, and if so – when ?
Will the comet hit the geostationary zone, and if so – when ?

The Attempt at a Solution


Don't know what to do?
Try applying Kepler's second law of planetary motion.

If its orbit barely intersected a) the Earth or b) the geostationary zone, how much speed would it have based on Kepler's second law?

Does it have enough energy to reach such a speed?

AM
 
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