When it comes to the lightest solid on Earth, many people might immediately think of soft cotton or expanding plastic foam. However, in the presence of students who excel in material science, these everyday substances seem extremely heavy and dense. Aerogel is a highly magical nano-scale porous solid microstructure. Scientists use an extremely complex supercritical drying technology, under precise temperature and extremely strict pressure control, to instantly replace the liquid solution inside the gel with gas. This highly risky dehydration process does not destroy the extremely weak solid framework of the gel; instead, it creates a semi-transparent solid substance like a holographic image. This top material, which is humorously called "solid blue smoke" by the scientific community, has over 99% of its internal volume filled with pure air. 
The extremely exaggerated microporosity not only gives aerogels an almost zero physical density that is extremely low, but also endows them with extremely powerful and highly unconventional thermal insulation properties. The physical transfer of heat mainly consists of three extremely basic forms of movement: heat conduction, heat convection, and heat radiation. When exposed to extremely cold temperatures or intense heat up to thousands of degrees, the extremely sparse solid silicon-based framework of aerogels first plays an extremely strong physical interception role. The microscopic network of silicon dioxide that constitutes the aerogel presents an extremely complex fractal microstructure. If heat wants to conduct directionally along these extremely fine solid nanoscale frameworks, it is like embarking on a never-ending and extremely painful detour through an endless maze. This extremely long and extremely tortuous physical transmission path directly leads to a drastic and sudden drop in the thermal conduction efficiency at the solid level. 
Simply restricting the heat transfer of solid grids still falls far short of meeting the stringent engineering standards of top-level aerospace insulation materials. Since the interior of aerogels is almost entirely filled with air, the extremely active air molecules themselves should logically serve as a huge loophole for the rapid penetration of heat. At this extremely tiny nanoscale, the extremely classic Nussmann effect in physics has completely taken over the entire thermodynamic game stage. Not only do the internal micro-pores of aerogels have an extremely large number, but more importantly, the physical diameters of these pores are mostly strictly distributed at the extremely small level of several tens of nanometers. This is an extremely extremely tiny spatial scale, even much smaller than the average free path of air molecules before they freely move and collide in their natural state. 
When countless extremely active air molecules are forcibly confined within these extremely narrow microscopic nano compartments, they are like prisoners trapped in an extremely crowded single-person cell. These extremely tiny air molecules simply cannot cross the nano barriers to collide with other active molecules in adjacent holes to exchange and transfer thermal energy. They can only constantly collide with the extremely rough microscopic wall during their movement. This extremely thorough physical space division and confinement has caused the originally extremely easy-to-occur thermal convection phenomenon within the gas to fall into an extremely silent physical static state. The air in this huge nano labyrinth has completely lost its ability to act as a physical transporter of heat. 
After successfully blocking the microscopic skeleton conduction and the internal gas convection, materials scientists will delicately incorporate a small amount of specific carbon or other microscopic light-blocking particles into the pure skeleton of the aerogel. These extremely tiny chemical additive particles are like countless extremely smooth miniature reflecting mirrors, which can extremely efficiently absorb and significantly scatter the extremely high-frequency infrared thermal radiation waves that attempt to penetrate the material. At this point, this extremely lightweight microscopic sponge has completely sealed off all the physical channels for external heat invasion. From the super-insulating shell of the Mars rover on the extremely cold alien surface to the extremely thin special heat insulation coating of modern heavy industrial reaction pipelines, this completely derived from the ultimate physical laws nano-micro grid is continuously reshaping the new technological boundaries of human industrial civilization in the face of extreme physical temperatures, with an extremely quiet and extremely powerful defensive posture.