So, how can we estimate R? In your lecture class you will nd out that the most distant parts of the Universe are moving away from us at nearly the speed of light , Let's assume that the largest distance an object can have in our Universe is given by the speed of light x the age of the Universe. Remember, if a car travels at 50 mph for one hour it will cover 50 miles (Distance = velocity x Time). We can use this equation to estimate the radius of the Universe: R Universe = velocity x time = (speed of light) x (age of Universe). a. The speed of light is a very large number: 3 X 103 mfs, and the age of the Universe is also large: '13 billion years. To calculate the radius of the Universe in m, we must convert the age of the Universe in years to an age in seconds (s). First, how many seconds are there in a year? Let's do the calculation: Seconds in year = (seconds in day) x (days in year) = (60 x 60 x 24) x 365 = sfyr Since this is only estimate, feel free to round off any decimals to whole numbers. Now that we have the number of seconds in a year, we can convert the age of the Universe from years to seconds: Age of Universe in seconds = (Age of Universe in Years) >