2 Improved body edit approved Nov 28 '13 at 8:29 a CVn 64755 silver badges2020 bronze badges E = mcsquared .$$E = mc^2$$ The morelarger the mass, the more energy can be produced. And we didnt still findhaven't found any fuel which gives so much energy within small quantities gives the needed amount of energy. I know uyou will be thinking of nuclear energy....weenergy; we cannot fit a nuclear reactor with current technology inside a rocket with current technology, and even if we can fit it I dontdon't think our existing knowledge of nuclear science is sufficient to ensure accident free-free reactors at such velocities.   E = mcsquared . The more the mass the more energy can be produced. And we didnt still find any fuel which gives so much energy with small quantities. I know u will be thinking of nuclear energy....we cannot fit nuclear reactor with current technology inside a rocket even if we can fit I dont think existing knowledge of nuclear science is sufficient to ensure accident free reactors at such velocities.   $$E = mc^2$$ The larger the mass, the more energy can be produced. And we still haven't found any fuel which in small quantities gives the needed amount of energy. I know you will be thinking of nuclear energy; we cannot fit a nuclear reactor inside a rocket with current technology, and even if we can fit it I don't think our existing knowledge of nuclear science is sufficient to ensure accident-free reactors at such velocities. 1 answered Nov 28 '13 at 8:09 E = mcsquared . The more the mass the more energy can be produced. And we didnt still find any fuel which gives so much energy with small quantities. I know u will be thinking of nuclear energy....we cannot fit nuclear reactor with current technology inside a rocket even if we can fit I dont think existing knowledge of nuclear science is sufficient to ensure accident free reactors at such velocities.