I have formulated a plan on how to destroy the world.
Remember in the Sydney 2000 Olympics, when some swimmers used body suits designed to reduce friction? Well, that material, which is called something like ny-lex or lato-ribex or something has been virtually perfected. It combines a special friction-reducing fabric (reducing friction much like Teflon), with ribulets, small V-shaped grooves in the fabric which help reduce resistance a further 10-15%, making friction effectively zero.
So what you do is this:
Take a large male adult African elephant, and dress him from head to toes in the friction-reducing fabric. Put him on the spaceship, and fly to about 150 miles up (about 240 kilometers). This will put you in the thermosphere, at about the maximum height where the elephant won't catch fire. Push the elephant out of the spaceship.
A large male adult African elephant weighs about 7 tons.
According to my quick calculations, an elephant free-falling for 150 miles without friction, should reach the ground (at sea-level) at a velocity of approximately 50,000 metres/second. Using the simple momentum calculation we all know from physics class (p = mv), the elephant's momentum should be about 7,000 * 50,000 = 350,000,000 kg m/s.
An elephant hitting the ground with such a momentum will deliver the equivalent of about 10,000 atomic bombs. This will create a crater 50 miles wide, and send enough dust into the atmosphere to block the sun's light for 200 years, killing all life forms on the planet.
I have been asked why not just drop the spaceship if you're already up there. Well, that's just silly. What would you drop it out of?