Hawking showed a screenshot of the video at the press conference. This nano-aircraft can be propelled by reflected light and accelerate to one-fifth the speed of light, which is much higher than the current spacecraft. Pang Zhihao believes that it is not difficult to propose the idea of a laser pointer “spacecraft” during the development of the existing solar sail technology. Maybe humans will develop a prototype of this kind of micro-aircraft around 2050, but it is still necessary to reach the Centaur. Not very realistic. There are mainly the following four major challenges:
The first challenge: the technical challenge of energy supply. It is understood that the “Breakthrough Photostar” program will release thousands of micro-spacecraft weighing less than 1 gram into space through satellites. Its design is like a butterfly with a sail on the back, using nanotechnology, powered by a laser beam. But this also faces huge challenges. 4.37 light-years away, and the energy of light energy will attenuate in the process of transmission. Therefore, how to ensure sufficient energy supply is a challenge.
At present, humans have produced small chip satellites that can orbit the earth, but the energy supply is generally only a few days or a few months, and only a few in the last year. The problem of energy supply is an obstacle that must be broken through interstellar navigation. An unmanned outer solar system space probe Voyager 1 developed by NASA was launched on September 5, 1977 and was still operating normally as of October 2014.
After nearly 40 years of flying, it has now entered the outermost boundary of the solar system. Voyager 1 carries two nuclear batteries. This is the energy guarantee for its space flight communication over the years, but it is only expected to be able to guarantee its continued flight until 2025. Once the battery is exhausted, it can no longer work and travel normally. The green laser pointer “spacecraft” in the “Breakthrough Shooting Star” program travels much farther than Voyager 1, and the energy supply challenge is greater, and its laser energy supply method is more complicated than nuclear energy.
The second challenge: how to solve the communication problem? In deep space exploration, communication issues have always been a very headache. For the spacecraft heading to the Centaur, it is also necessary to determine whether the ground can receive detection data and whether it can achieve measurement and control communication at such a long distance.
Pang Zhihao said that the U.S. Voyager 1 arrived at the edge of the solar system, and there was a 17-hour delay in communication with the earth. If the existing electromagnetic wave communication methods are used, the time to reach Alpha Remy Martin will be more serious, and this will seriously affect the measurement and control communication, and also affect the advancement of the exploration project.