At a 3 percent growth rate, its doubling time â or the number of years to double in size â is 23 years. (The doubling time for a population can be roughly determined by dividing the current growth rate into the number 69.. Therefore, 69/3=23 years.
But the attempt was scrubbed about an hour before launch due to the helium leak. Todays launch has been scrubbed due to a helium leak on Falcon 9's first stage, SpaceX officials announced in an update today. A fix will be implemented by the next launch opportunity on Friday April 18, though weather on that date isn't ideal. [ See photos of SpaceX's 3rd Dragon mission to the space station ].
It was a much more difficult task than building solid-propellant rockets. Fuel and oxygen tanks, turbines, and combustion chambers would be needed. In spite of the difficulties, Goddard achieved the first successful flight with a liquid-propellant rocket on March 16, 1926. Fueled by liquid oxygen and gasoline, the rocket flew for only two and a half seconds, climbed 12.5 meters, and landed 56 meters away in a cabbage patch.