Photon rocket is a promising power device for interstellar navigation, but the engineering problems are difficult to solve. For example, the photon beam emitted by photon mega is so powerful that as long as one millionth of the heat leaks into the spacecraft, it is enough to burn the spacecraft. For another example, the huge energy generated by photon mega emission will cause serious damage to the earth's environment, so the spacecraft propelled by photon rockets must be far away from the earth to ensure safety. At present, several research groups are studying photon rockets, such as Marshall Space Flight Center and Hughes Laboratory in the United States. It is predicted that photon rockets may be put into practical application in 2040-2050.

In fact, in a word, photon rocket is just an idea at present.