In the past, asteroids striking the earth have produced disastrous results. If we discovered an asteroid on a collision course with the earth, we could, in principle, deflect it and avoid an impact by focusing a laser on the surface. Intense surface heating from the laser could cause surface material to be ejected into space at high speed. How would this deflect the asteroid?

Consider the observation that the acceleration due to the gravitational force acting on a mass around a host planet decreases with the square of the separation between the objects. We can ask ourselves: why is it still accurate to consider a gravitational acceleration value of 9.8\frac{m}{s^2}9.8s2m​ for all of our projectile motion problems and all of our gravitational potential energy from prior modules?    Let's analyze a situation and justify this analysis method: consider an object being launched from ground level to an altitude of 10,000 meters, roughly the cruising altitude of most jet liners, and far above our everyday experiences on Earth's surface. Compare the gravitational acceleration of the object at Earth's surface (the radius of Earth is about r_E=6.37\times10^6mrE​=6.37×106m) to the acceleration value at the 10,000 meter altitude by determining the following ratio: g10,000m/gsurface

On February​ 15, 2013, Asteroid 2012 DA14 passed within​ 17,200 miles​ [mi] of the surface of the Earth at a relative speed of 7.8 kilometers per second​ [km/s]. This is considerably closer than the orbit of geosynchronous satellites​ (26,200 miles). This is the closest recorded approach of an object this large. The asteroid 2012 DA14 was estimated to have a diameter of 30 meters​ [m] and a specific gravity of 3. If 2012 DA14 had hit the​ Earth, what is the total amount of energy that would have been released​ (i.e., what was the kinetic energy of the​ asteroid)? Express your answer in megatons​ [Mton]. One megaton is the energy released by one million metric tons of TNT explosive. A metric ton equals​ 1,000 kilograms​ [kg], and the explosive energy of TNT is 4,184 joules per gram​ [J/g].

more than one answer can be correct

How much energy is required to lift a 10 kg rock from the surface of the Earth and place it in a circular orbit just 10 km above sea level? Assume Earth's radius is about 6371 km.

Let’s imagine that you have an idea for an experiment to fly on NASA’s “Vomit Comet.” (What’s special about this plane? It flies in parabolic paths (aka freefall) which result in near weightlessness. This means that you can ignore the effects of gravity when plan your experiment.) You want to mimic the orbital motion of the planets but by using electrostatic force rather than gravitational. And, instead of a planet, you will be orbiting a droplet of water that is 0.5mm in radius and has an deficit of 1.5 x 106 electrons. The droplet is to orbit around a small (1cm radius) sphere. If you want the droplet to move with an orbital radius of 14cm and period of one minute, what should the charge be on the central sphere? BTW The density of water is 997 kg/m3.

a) What is the total energy needed to place a 2.0 x 103 kg satellite into circular Earth orbit at an altitude of 5.0 x 102 km? b) How much additional energy would have to be supplied to the satellite once it was in orbit, to allow it to escape from Earth’s gravitational field?

You're designing a mission with a special type of rocket, a nuclear thermal rocket (NTR). Since it uses a nuclear reactor to heat the propellant, it can achieve an exhaust velocity of vex = 5.65 km/s. The crew's habitat space, the rocket itself, the shadow shield to protect from radiation, and the instrument payload for scientific research all have a combined mass of 607 x 103 kg, and the propellant is 3,638 x 103 kg. What is the total delta-V of the rocket in km/s?

A black hole is an object so massive that not even light can escape, one way to define the size of a black hole is by the Schwarzschild Radius, which is the radius at which the escape velocity is equal to the speed of light. If we were to condense the Earth into a black hole, what would be the size of its Schwarzschild Radius?

What is the escape velocity is km/s from Jupiters exosphere, which begins about 993 km above the surface ? Assume the Gravitational constant is G= 6.67 x10-11m3 kg-1s-2, and that's Jupiter has a mass of 1.8999999999999998e+27kg and a radius of 68.0 x103km