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21
Historical Spaceflight / Re: Astronaut Hall of Fame
« Last post by hektor on Today at 07:14 pm »
Thanks a lot.

There was a kind of centrifuge for the public there. Is it known what happened to it.
22
Commissionner Breton is not enthused by SUSIE:

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THIERRY BRETON-The Susie program is very interesting. It is a project that offers an opening for the next decade. We will look at it with great interest because it is indeed a major subject. However, it is very important in the field of space - especially in the geopolitical moment in which we find ourselves - to target our priorities well, but also to have a medium- and long-term vision, in which manned spaceflight is obviously part. The short-term priorities are to ensure European programs and projects, which are linked to our sovereignty and autonomy in the various segments perfectly identified in the framework of the strategic compass

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THIERRY BRETON-Le programme Susie est très intéressant. C'est un projet qui offre une ouverture pour la prochaine décennie. Nous allons le regarder avec beaucoup d'intérêt parce qu'effectivement c'est un sujet majeur. Toutefois, il est très important en matière d'espace - surtout dans le moment géopolitique où nous nous trouvons - de bien cibler nos priorités mais aussi d'avoir une vision de moyen et long terme dans lequel s'inscrivent évidemment les vols habités. Les priorités de court terme sont d'assurer les programmes et projets européens, qui sont liés à notre souveraineté et à notre autonomie dans les différents segments parfaitement identifiés dans le cadre de la boussole stratégique.

https://www.latribune.fr/entreprises-finance/industrie/aeronautique-defense/spatial-la-cooperation-avec-la-russie-est-definitivement-bannie-thierry-breton-934100.html
23
SLS was supposed to be ready by the end of 2016. If you assume another $2.64B per year for FY15 and FY16, you get very close to the $11.5B that Nelson was indicating.
Correction, the SLS was supposed to be OPERATIONAL by the end of 2016. From Senate Bill S.3729:
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Developmental work and testing of the core elements and the upper stage should proceed in parallel subject to appropriations. Priority should be placed on the core elements with the goal for operational capability for the core elements not later than December 31, 2016.
That means all testing had to be done before that point, so that they could certify the SLS as operational.
In the context of the 2010 NASA Authorization bill, operational capability just meant that you can operate and use it.

Since Congress didn't define what "operational capability" means, in the normal sense that means that testing is done and the transportation system has been certified for normal use. That is what "use it" means, and it does not mean "testing".

So I'm not sure you are disagreeing with me on this, and I'm not sure why you are bringing it up?

It's possible that we are agreeing. I didn't fully understand what you meant. To me operational capability will be reached on Artemis II (not Artemis V). If that is what you meant, then we agree.
24
Let me clear up a few things that are *often* confused (or misconstrued…) by many people in these conversations:

COSPAR is not applicable to SpaceX Starship missions to Mars for two reasons:
1) NASA only applies the COSPAR rules to robotic missions with the explicit understanding that human missions need new rules (note that COSPAR themselves don’t always agree with this, but COSPAR isn’t law & have no independent enforcement mechanism… purely advisory… it applies to NASA robotic missions because NASA *chose* to apply its rules).

2) SpaceX doing Starship missions are non-NASA and COSPAR is only enforced for some *NASA* missions (robotic ones).

Yes, the US is (voluntarily!) bound by treaty to limit *HARMFUL* contamination. “Harmful” is a key part of the phrase, often omitted by the COSPAR folk… so you cannot use claims by COSPAR folk without a healthy grain of salt. Ththinkthinkthinke bar for meeting the treaty obligations is much, *much* lower than COSPAR rules for robotic missions.
Presumably someone is going to have to interpret "harmful" contamination in the context of whatever mission profiles SpaceX come up with. I'd like to think that SpaceX and NASA are constantly evaluating this, and that sane heads are balancing the opposing views.
25
Rocket Lab / Re: Archimedes Engine Discussion.
« Last post by baldusi on Today at 06:44 pm »
Sure, but you’re exchanging higher temperature fuel-rich environment for a lower temperature oxygen-rich one. That’s not necessarily a better trade, metallurgically.
Mr. Beck has stated that no new material development was needed. I would assume, thus, that they were able to lower the temperature to a point where it just doesn't matter that it is, in fact, oxidizer-rich.
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New video about a full TAL to Istres


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I was hoping for actual date guesstimates: timing is everything. If there are only one or two Crew Dragon flights left after Starship is certified, then SpaceX will eat the loss and fly Crew dragon at a loss once or twice, and maybe keep flying Cargo Dragon for CRS. If there are (say) four more CCP flights after Starship is certified, they might get creative and come up with a way to use Starship.
28
Concerning artificial gravity, I decided to play with a few numbers on spincalc for a simple jogging track.

The typical jogging speed on earth is about 4-6m/sec (https://www.healthline.com/health/average-jogging-speed)
Allowing for some hull and shielding thickness, a track might conservatively have a 4m radius. (8m diamiter+1/2m hull/shielding on each end)

At 4m/s floor tangent and a 4m radius, your feet will be experiencing 0.4g at 9.55 rotations per minute
At 5m/s floor tangent and a 4m radius, your feet will be experiencing 0.637g at 11.9 rotations per minute
At 6m/s floor tangent and a 4m radius, your feet will be experiencing 0.918g at 14.3 rotations per minute

Assuming a 2m tall person, their head will have the same rotation per minute as their feet but a 2m radius of rotation.


At a 2m radius, your head will be experiencing 0.2g at 9.55 rotations per minute
At a 2m radius, your head will be experiencing 0.32g at 11.9 rotations per minute (just below marsG)
At a 2m radius, your head will be experiencing 0.46g at 14.3 rotations per minute

This assumes the starship itself is not spinning at all- this is strictly individual movement, so intermediate axis isnt even an issue. These G loads dont seem unreasonable, though the difference between head and foot might take a bit of getting used to.

Also, this doesnt even need a specialised ship- you could easilly have a jogging track/outer corridor in the lunar starship for physiological testing between excursions.
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