pjb wrote:
Wrong. You need more fuel than to just get away from the earth, because once you do that, the missile is still in an orbit about the sun. You need to get it into an orbit that intersects with the sun. This would either take quite a bit of fuel or, if travel time is not an issue, a carefully-plotted trajectory that will use a gravity-assist from a planet, which would still require extra fuel, albeit less. Sending it on a trajectory into the sun from the earth would require not just escaping earth's gravity, but also accelerating to counter most of the earth's 30km/s orbital velocity to allow the missile to fall more-or-less directly into the sun.
Well, it took nearly forty posts; but, finally, somebody said something that is correct! That poor fellow looking for astronomers on LetsRun a few days ago certainly got his answer in this thread: they are few and far between here! The comments in this thread are a perfect example of why it is so easy to dupe most people when it comes to describing how the natural world works.