NASA has published a video about flights at near light speed. For maximum clarity, the agency
So, the demonstration was based ona promising project Breakthrough Starshot, in which a small probe with a solar sail will be sent to Alpha Centauri. It is planned that not only the Sun will be responsible for its acceleration, but also a super-powerful laser from the Earth - all this will allow the device to accelerate to about 20% of the speed of light.
Interestingly, the near-light flight projectspeed has a lot of problems. So, for example, it is still unclear, but if a breakdown occurs and you have to go into outer space for repairs, what will this threaten the astronauts? Also, it is impossible to say for sure how to ensure reliable shielding of the ship from the external environment, which is not at all a pure vacuum, but is filled with various kinds of space objects? Science has yet to answer all these questions in the future.