Selecting a target asteroid

There are a lot of Asteroids in the Solar System. It can be tough to figure out which may be the best candidates for mining. There are two ways to select narrow down which asteroids may be good candidates:

1. $ Value of the Asteroid resources
2. Cost to get to the Asteroid

To put it simply, if the value of the resources available on the Asteroid is comfortably higher than the cost of getting to the Asteroid, it may be a good candidate for mining. Of course, a lot more analysis is needed to finally select an asteroid for target, but this is a good starting point.

$ Value of the Asteroid resources

Estimate of the total value of the mineral resources available on the Asteroid. There are some websites like the Asterank database, which provide an estimate of the $ value of the potential mineral resources available on the Asteroid. This is a good starting point for an estimate, but no one really knows for sure what the true value of minerals from the asteroid will be.

Cost to get to the Asteroid: 

This is the other side of the equation, i.e. what is the cost of getting to the Asteroid. This is usually expressed as Δv, which represents the impulse needed to get into an orbit which can reach the Asteroid. Even though the unit is the same as speed, this doesn’t represent the speed, but the impulse. 

To estimate the Δv, a trajectory needs to be planned. This is usually pretty complicated, but a good enough estimate can be made using the Trajectory Browser from NASA. This uses the Hohmann transfer maneuver. For using Ion Thrust Engines, different methods are needed.

Once we know the Δv, we need to calculate the amount of propellant required, which can be estimated using the  Tsiolkovsky rocket equation. 

Finally, you can calculate the cost of your trip by multiplying the weight of the propellant by $10,000 / Kg, which is the cost to send payload to LEO.