I vote the force involved breaks the laws of physics
No, no, it will work. If you have a long enough track for the mass driver
to launch from it can make it into space. However it need to be REALLY big and have a lot of power. Geothermal should enough enough power and getting it up to at least 2 km should do it. However its easier to launch from the equator than the poles. So we might need it a little bigger if its to launch from between them. It also would help if it started higher in elevation and its seed was smaller. Also if we are launching microbes, g-forces are not as much of a problem than if it was for say a macro species. In addition the current seeds have their own "rockets" which means the launcher can get it to high speeds while the rocket helps propel it the rest of the way.