Astronomer class

Question

What speed would be required in order to reach the nearest star within a reasonable travel time of 10 years? Give your answer in units of kilometers per year (km yr^-1)

Answer 1

First, lets' figure out where we are looking, the nearest star to us is roughly 4.35 light-years away.

Step 1:

Since we have the distance in light-years but the answer is looking for it in km, let's start doing a unit conversion

Where one light-year is 9.46•10¹²km

(4.35ly)(9.46•10¹²km / 1ly) = 4.115•10¹³km

Step 2:

Now that we have the distance and we are asked to find the speed we must travel at. Note that speed is looking at only the time rate an object is moving

Lets us the speed formula

s = d/t

d= distance traveled

t = time

When we plug in 4.35•10¹³km for d. And ten years for t.

The formula will be

s = (4.35•10¹³km)/(10 years)

s = 4.35•10¹²km/yr