1. Researchers have developed a method for sustained flight in the Earth's mesosphere using photophoresis or light-driven motion.
2. They levitated centimeter-scale disks made of commercial mylar film coated with carbon nanotubes on one side, using a shaped light field that optically trapped the levitating disks.
3. The lift forces can be many times the weight of the films, allowing payloads of up to 10 milligrams for sunlight-powered low-cost microflyers at altitudes of 50 to 100km.
The article titled "Controlled levitation of nanostructured thin films for sun-powered near-space flight" discusses the potential use of photophoresis or light-driven motion as a mechanism for sustained flight in near space. The authors report on their experiment with levitating centimeter-scale disks made of commercial mylar film coated with carbon nanotubes on one side, which were able to lift payloads of up to 10 milligrams at altitudes of 50 to 100km.
While the concept of using photophoresis for near-space flight is intriguing, the article has several potential biases and limitations that should be considered. Firstly, the study only focuses on levitating macroscopic polymer films with nanostructured surfaces, and it is unclear whether this method would work with other materials or structures. Additionally, the authors do not provide any evidence or discussion about the potential risks or drawbacks associated with using this technology for near-space flight.
Furthermore, the article seems to present a one-sided view of photophoresis as a viable solution for sustained flight in near space without exploring alternative methods or counterarguments. The authors also make unsupported claims about the lift forces generated by their levitating disks without providing sufficient evidence or data to support these claims.
Overall, while the concept presented in this article is interesting and potentially promising, more research and exploration are needed before it can be considered a viable solution for sustained flight in near space. The authors should also provide a more balanced view of photophoresis and its potential limitations and risks.