Interstellar Travel Feasibility: Speeds, Propulsion, and Engineering Challenges

To the point

Interstellar travel is theoretically possible but practically extremely hard because it needs enormous energy, advanced propulsion, and perfect shielding, so with current tech such voyages are likely infeasible; if one did arrive, it would prompt deep questions about its origin and motives.

Could aliens visit Earth? Scientist breaks down how interstellar travel works
the-independent.com

Could aliens visit Earth? Scientist breaks down how interstellar travel works

To assess the plausibility of alien visitors, it’s necessary to understand the obstacles that an extraterrestrial vessel would need to overcome to reach Earth