One of the greater challenges of sending payloads to Mars is contending with the planet’s atmosphere. While incredibly thin compared to Earth’s (with roughly half of 1 percent of Earth’s air pressure), the resulting air friction is still an issue for spacecraft looking to land there. And looking to the future, NASA hopes to land heavier payloads on Mars, as well as other planets—some of which may have atmospheres as dense as Earth.
Source:
https://phys.org/news/2019-06-inflatable-shield-heavy-payloads-worlds.html