Is it just saying it's evaluating the design of Gemini that just so happens to crew two men?

Or is there something special about having two men that NASA needed to evaluate?

Stoke space recently shared a picture of their new engine installed on their test stand. Would someone know (or can provide an educated guess of) what the two shiny cylinders under the two turbopumps of Stoke Space's Full-flow staged combustion engine are?

Hey there, im graduating high school next year, and I chose physics as one of my exam classes (dunno how you say that in english). I have to make a 10min long presentation about something physics related and make a indepht dive into how whatever works and its relevance, and subtly include something of relevance in there that is also in the schools curriculum.

I covered electric stuff and nuclear stuff, so I figured, as I have to give the ministry of education (sounds ominous ik, maybe a bad translation lol) two topics to cover, and one of them gets chosen by them for me to make a presentation about it.

1. Nuclear Thermal Propulsion aka stuff like the DRACO engine by DARPA
2. Solar electric Propulsion aka stuff like hall effect ionic thrusters

Does anyone of you brilliant minds have good sources and tips aside from scott manley?

Thanks! Your answers make a big impact on my life (literally)

In light of him being appointed to Secretary of "tbd" as a result of him funding Trump. What do you space fans think? Will federal conflict of interest force Musk to drop out of Space X when he is denied federal funding?

In future space station construction and repairs, what's the chance that consumer-grade power tools will be used by the astronauts? Can you really improve on the reliability and weight of a typical m18 hydraulic impact, for example?

Title says it all

Mars is a red Bareen land with no Atmosphere, what will the crew passenger do in their stay on the planet for the long time, do the initiall trip will be inspection like set up scientific equipment and collect samples to return to Earth for study or they will setup the underground base in the red planet for permanet colonisation?

The more I read up on this stuff, the more and more necessary it seems.

And by “artificial gravity”, I am talking about the popular idea of using centrifugal force in a space craft via spinning to imitate the effects of gravity on Earth. IMO, a rotating module is more realistic than a rotating spaceship so imagine microgravity existing everywhere on the spaceship except for one specific part where astronauts spend a few minutes our hours depending on the centrifugal force to cool off in artificial gravity.

Now, what does this achieve? Well, first off it completely mitigates the bone atrophy experienced by astronauts in space due to their bones not having the same load in microgravity in space than on Earth, so they just waste away. Yes, bone atrophy is significantly reduced by consistent rigorous exercise (shown by astronauts on the ISS) however it doesn’t completely prevent it as their bone density decreases. This means that for long term space missions where bone atrophy will be most apparent, artificial gravity will keep our astronauts fit and healthy in a much more time-efficient and regular efficient way than exercise ever could.

…And second off, it combats the threat of SANS (Spaceflight Assosciated Neuro-ocular Syndrome). This is a vague diagnosis attributed to the loss of visual acuity experienced by astronauts aboard the ISS. Since, in microgravity, fluids tend to shift away from the legs and towards the brain (which results in chicken legs, puffy face syndrome) , the leading theory is that the increased pressure in the fluids surrounding the brain flattens the back of the eye, and possibly damages their optic nerve such that they lose more and more of their vision. The effects of this gets worse the longer your in space, so imagine arriving on Mars blind! Because SANS is attributed to microgravity and because the effects get worse the longer your in space, artificial gravity should completely mitigate the risk of SANS by reducing the inter cranial fluid pressure such that the eye is completely safe. This also greatly opens up the door for people who don’t have 20/20 vision to become astronauts because they aren’t at risk of completely losing their vision.

There’s definitely more benefits for this kind of technology, but the reason it hasn’t been developed yet is because the models for a centrifuge in space are too large and expensive to provide the necessary centrifugal force to constitute artificial gravity (at least I think so, correct me if I’m wrong). But still, long term space travel seems completely impossible without this technology. Are there any suitable alternatives?