SpaceX Crew-4 Launch

After a series of postponements due to weather-induced delays in the return of the Axiom-1 crewed mission to the International Space Station (ISS), which used the same docking port, NASA’s Crew-4 mission is scheduled to launch on 2022-04-27 at 07:52 UTC. The mission will take four astronauts, three from NASA and one from the European Space Agency, to the station for a six month stay. They will fly to the ISS in a new Crew Dragon vehicle named Freedom. The first stage booster, B1067, will be making its fourth flight. Weather is forecast as 90% favourable for launch. Here is a pre-flight preview from Everyday Astronaut.

The new Freedom Crew Dragon spacecraft features additional amenities including USB charging ports (only in business class).

On 2022-04-26, NASA held a pre-launch media teleconference about the flight, of which the following is an audio-only recording.


Live stream of approaching and docking with the International Space Station. Unless there is a need to intervene, the docking is entirely autonomous.

On 2022-10-14, the Crew-4 astronauts returned to Earth in the Crew Dragon Freedom in which they launched on 2022-04-27.

Here is the Crew Dragon undocking from the International Space Station.

This is the re-entry, splashdown, and recovery.


Here is the post-landing NASA/SpaceX media teleconference on the conclusion of the Crew-4 mission. This is an audio-only recording.

6 months in zero-g seem to take a toll on the four astronauts that returned Friday. How long does it take a well trained astronaut to recover after coming back? And doesn’t this call into question the feasibility of anything like flight to Mars and back?


Although most people are back to normal in terms of getting around and doing things within a couple of days after returning from a long-duration space flight, there are long term effects which take an extended period of time for recovery and may never be fully eliminated. Here is a NASA report of a study that indicates that, despite a rigorous exercise regime (2.5 hours a day, 6 days a week), astronauts on long duration missions to the ISS lost around 11% of their hip mass during the flight. A year after return to Earth, they had not regained either normal bone structure or mass, which may take much longer (if ever). A typical astronaut on orbit loses as much bone mass in one month as an elderly woman does in a year.

This is obviously a problem for any mission contemplating long-term exposure to microgravity, and it isn’t the only one. Microgravity is also known to impair cardiovascular system performance, increase cranial and interocular pressure, and suppress immune response.

It is remarkable that in more than 50 years of human space flight, nobody has done any serious experimentation with artificial gravity produced by spinning spacecraft. We had a post here on 2022-10-09, “Artificial Gravity for Long-Duration Space Flight”, on this topic.

As I noted in that post, beyond microgravity, nobody knows what effects long-term exposure to lunar or Mars gravity will do to humans. A habitat in Earth orbit with artificial gravity would allow experimenting with this before establishing bases in those environments.


Maybe the body habitus of Jabba the Hutt is a prescient rendering of human adaptation following zero-G reproductive activities and permanent habitation in space; provided, of course, a spermatozoon can be induced to hook up an ovum following the requisite zero-G contortions. The prospect is almost sufficient to tempt me to voyeurism…


Thank you for sharing the Marcus House video – while theoretically feasible, all those ideas would be quite expensive and take a long time to build. Since up to now so little attention has been given to the practical aspects of long term life in zero or micro-gravity environments, is it likely anything would change in the next 5-10 years?

It would really be a bummer to have a long awaited Mars manned mission fail on account to humans on board turning to jelly (metaphorically) by the time they get there or come back.

Space is a super harsh environment for humans.


We already have experience with people living in microgravity longer than a trip to and from Mars. As long as they exercise as they do on the ISS, there should be no problem arriving at Mars or back at Earth.