There are plenty of crazy ideas for missions in the space exploration community. Some are just better funded than others. One of the early pathways to funding the crazy ideas is NASA's Institute for Advanced Concepts. In 2017 and again in 2021, it funded a mission study of what most space enthusiasts would consider only a modestly ambitious goal but what those outside the community might consider outlandish—landing on Pluto.

Two major questions stand out in the mission design: How would a probe arriving at Pluto slow down, and what kind of lander would be useful on Pluto itself? The answer to the first is one that is becoming increasingly common on planetary exploration missions: aerobraking.

Pluto has an atmosphere, albeit sparse, as confirmed by the New Horizons mission that whizzed past in 2015. One advantage of the minor planet's relatively weak gravity is that its low-density atmosphere is almost eight times larger than Earth's, providing a much bigger target for a fast incoming aerobraking craft to aim for.

The first all-civilian space mission is shedding light on the potential health risks facing private astronauts. The takeaway is short-duration spaceflights appear to pose none that are significant. The study sample was small—four people who spent three days in low-earth orbit (LEO) on the 2021 Inspiration4 mission.

But it lays the groundwork for an open biomedical database for commercial astronauts' health data and establishes best practices for collecting and dealing with this information, according to a team led by Baylor College of Medicine's Center for Space Medicine in Houston.

"Civilian participants have different educational backgrounds and medical conditions compared to astronauts with career-long exposure to space flight," said study co-author Dr. Emmanuel Urquieta, chief medical officer of the Translational Research Institute for Space Health (TRISH) at Baylor.

"Understanding their physiological and psychological responses to spaceflight and their ability to conduct research is of utmost importance as we continue to send more private astronauts into space."

Like astronauts who do months-long tours of duty on the International Space Station, the hazards facing these four included radiation exposure, sustained microgravity, confinement and isolation.