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This is more like a fait accompli such that Bigelow is saying that the DSG development program for a habitat is unnecessary and that Bigelow would lease or sell them the delivered B330 for <$1B. Current estimates for the development program for the DSG habitat is for several $billion and would have a deployment date in the NET 2025 timeframe. Bigelow is telling NASA that they can pay them for the habitat once it is there and just stop trying to develop their own habitat version.
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Commercial Space Flight General / Re: EXOS aerospace
« Last post by vaporcobra on Today at 10:11 PM »
Misidentified this initially and was told that it is an EXOS stand and engine :)
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But as I recall ULA has stated that ACES is mandatory for Vulcan in order to fully replace their Delta IV Heavy, so that has always been their planned timeline.

Not ACES specifically, a wide body Centaur will do, which is what they will launch with the first Vulcan. ULA will release more details when their proposal is out.
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This is an odd one. Looks a lot like a Merlin to me, but the hand for scale on the lower right suggests it's too small, and the odd trailer-esque setup does not look familiar, nor does the giant white sphere thing. Also looks too big to be a BE-3, and the geotag is in Dallas with the suggestion that the poster's "neighbors" are rocket scientists. McGregor is about an hour and a half south of Dallas.
That is the EXOS Aerospace engine and test stand.

Nice catch. I need to follow EXOS more closely :)
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We do know how time dilation induces gravitational effects.
We do not know that it does. In fact to the contrary, gravitational effects cause time dilation, not the other way around. Saying that we know how something happens that does not happen is 2 levels of wrong.

In the presence of a variable 'rate of time' the geodesic paths are accelerated - like gravity. Newtonian gravity can be accounted for by only varying the rate of time. GR requires changes in the space dimensions as well.
Newtonian gravity does not have any time dilation. also, "rate of time" is not a defined physics term, so I am just assuming you mean "time dilation."
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We don’t even know that it’s a DOD mission. We’ve only been told government client. While DOD may even be likely, it could be another arm of the government. Ideas for what other gov’t client it could be besides DOD?

Edit: removed question about being US gov’t after reviewing posts above. It’s definitely US gov’t.

It's either military or intelligence agency, otherwise it wouldn't be a secret.
Hey, there's only 17 or so US intelligence agencies, so should be easy to narrow down.
...and four branches of the military...
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Advanced Concepts / Re: Quantum Computing & Artificial Intelligence
« Last post by Star One on Today at 10:06 PM »
AlphaGo Zero: Learning from scratch

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Artificial intelligence research has made rapid progress in a wide variety of domains from speech recognition and image classification to genomics and drug discovery. In many cases, these are specialist systems that leverage enormous amounts of human expertise and data.

https://deepmind.com/blog/alphago-zero-learning-scratch/

Here’s the relevant paper.

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A long-standing goal of artificial intelligence is an algorithm that learns, tabula rasa, superhuman proficiency in challenging domains. Recently, AlphaGo became the first program to defeat a world champion in the game of Go. The tree search in AlphaGo evaluated positions and selected moves using deep neural networks. These neural networks were trained by supervised learning from human expert moves, and by reinforcement learning from self-play. Here we introduce an algorithm based solely on reinforcement learning, without human data, guidance or domain knowledge beyond game rules. AlphaGo becomes its own teacher: a neural network is trained to predict AlphaGo’s own move selections and also the winner of AlphaGo’s games. This neural network improves the strength of the tree search, resulting in higher quality move selection and stronger self-play in the next iteration. Starting tabula rasa, our new program AlphaGo Zero achieved superhuman performance, winning 100–0 against the previously published, champion-defeating AlphaGo.

https://www.nature.com/nature/journal/v550/n7676/full/nature24270.html
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Plus, plans for ACES haven't changed. Tory Bruno just retweeted this a few minutes ago: https://twitter.com/WeAreGoFL/status/920684164202057729

Yes, then in answer to the very question you are asking, Bruno said:

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ACES baseline remains unchanged.  Bigelow agreement recognizes possibility of pulling fwd with need and funding

Especially for ULA, who parents HATE to build things that don't have customers, this is not surprising.

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ACES is very ambitious in a number of ways, lots of things that haven't been done before and need testing. Yet, we are still waiting for ULA to so much as choose an engine for it. It's not a generic stage that just needs to get done. It's new technology that takes time to develop and it's also not worth focussing the entire company on developing it, just to get that one payload into space by 2022.

Many would find it hilarious that I am defending ULA, but you have to understand how "Old Space" does things vs "New Space". ULA is still rooted in "Old Space" thinking (because of it's parents) which means that they tend to pursue mature markets and try to only accept minimal risk. SpaceX ("New Space") is OK with lots of risk, and is trying to create new markets by dramatically lowering the price to move things to space. LM and Boeing have been very successful overall with their approach so this comparison is really only in a very narrow market, the launch services sector- which SpaceX has been disrupting.

But as I recall ULA has stated that ACES is mandatory for Vulcan in order to fully replace their Delta IV Heavy, so that has always been their planned timeline. This Bigelow announcement requires U.S. Government money in order to start the 4-year clock on being ready to launch, which is reasonable for ACES.

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It makes absolutely no economic sense and the company just isn't doing it either. So why announce it? Why say "This lunar depot could be deployed easily by 2022"?

Because they feel, given enough money from the U.S. Government, that they could make the date. I'm not sure about Vulcan (nothing specific, just new), but I think ACES is definitely doable.

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Even Elon Musk makes it clear where his time frames are extremely optimistic - and those are about Mars settlements, not business engagements.

Elon Musk is great at telling people what is possible, and SpaceX has been very good at then making things possible. I see this announcement in the same vein, that they are announcing to a very specific group of people (i.e. the President, V.P., NSC, and Congress) that if America wants to go back to the Moon that they could help that come true - much sooner than what NASA can do with the SLS and Orion.
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SpaceX Mars / Re: Elon Musk Reddit AMA on BFR
« Last post by oldAtlas_Eguy on Today at 10:00 PM »
If the 'hover-slam' is a solvable control problem with a single engine, it isn't much of a stretch to envision a 'hover-tip' maneuver with multiple engines firing off-center.  The stack is tilted during descent to prevent XY acceleration, with Z velocity and now also deviation from vertical reaching 0 precisely at touchdown.  It's obviously harder, with additional trades needed WRT landing gear, but not unsolvable.

Coslne losses suggest it might use more fuel than is absolutely necessary though, no?


The gimbal angle can't be all that big and cos(12 degrees) is 0.978 so the losses are a few percent or less.


If you're landing on fumes, it does matter. but yeah.
A fallacy.

Other than for maneuvering X-Y the angle of thrust is center-lined on the CG. So there is no cosine losses on engine out unless for some reason the engines are gimbaling not in unison but gimbling in opposition.
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Spaceflight Entertainment and Hobbies / Re: Star Trek Discovery
« Last post by Blackstar on Today at 09:58 PM »
And if you're like me (and I know that I am...), then you dislike what they've done with the Klingons. Fortunately, there are people out there who are fixing their work. Here's a proper Klingon D7 cruiser:



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