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Artemis 3 Mission in 2024



 
 
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  #11  
Old July 26th 19, 01:00 PM posted to sci.space.policy
David Spain
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Default Artemis 3 Mission in 2024

On 7/26/2019 7:37 AM, Jeff Findley wrote:
Plus such an approach nicely dovetails with building earth orbiting
space stations and the like.

The actual Space Race was short and sweet and sent us down the dead end
of large expendable launch vehicles. Unfortunately, NASA has gone down
that same dead end yet again with Ares/SLS. It's simply not
sustainable.

I write this on the morning after Starhopper made its first successful
hop. This was the first flight of a full flow staged combustion liquid
fueled rocket engine. That is a sustainable, reusable, approach to
spaceflight. I'm glad SpaceX is pursuing this, because NASA dropped the
ball long ago on reusabilty.

Jeff


Yes, this was great news. I'm still trying to find a decent video of the
event, but it's early. I haven't had my coffee yet.

Jeff I couldn't agree more with all your points. Expendables are exactly
that and a dead end.

Elon Musk has a great analogy to that. Imagine air travel involved a
parachute that you use to jump out of the airplane over your destination
while the aircraft continues to fly out over an uninhabited area, runs
out of fuel and crashes either into the desert or the ocean.

That's what we have for a space program today with expendables in
Orion/SLS. We need to expend that paradigm.

Dave

  #12  
Old July 26th 19, 02:19 PM posted to sci.space.policy
Niklas Holsti
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Default Artemis 3 Mission in 2024

On 19-07-26 15:00 , David Spain wrote:
On 7/26/2019 7:37 AM, Jeff Findley wrote:

...
I write this on the morning after Starhopper made its first successful
hop.

...
Yes, this was great news. I'm still trying to find a decent video of the
event, but it's early. I haven't had my coffee yet.


The on-board engine view is nice, one can see the ground falling away...

https://www.youtube.com/watch?v=eaBMqs1z9cc

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  #13  
Old July 26th 19, 02:23 PM posted to sci.space.policy
David Spain
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Default Artemis 3 Mission in 2024

On 7/26/2019 9:19 AM, Niklas Holsti wrote:
On 19-07-26 15:00 , David Spain wrote:
On 7/26/2019 7:37 AM, Jeff Findley wrote:

Â*Â* ...
I write this on the morning after Starhopper made its first successful
hop.

Â*Â* ...
Yes, this was great news. I'm still trying to find a decent video of the
event, but it's early. I haven't had my coffee yet.


The on-board engine view is nice, one can see the ground falling away...

https://www.youtube.com/watch?v=eaBMqs1z9cc


Nice, you can see the shock diamond form as the raptor throttles up.
Thanks for the link.

Dave
  #14  
Old July 26th 19, 08:44 PM posted to sci.space.policy
Scott Kozel
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Default Artemis 3 Mission in 2024

On Friday, July 26, 2019 at 6:32:13 AM UTC-5, Jeff Findley wrote:
In article ,
says...

On Thursday, July 25, 2019 at 6:46:32 AM UTC-5, David Spain wrote:
On 7/24/2019 8:07 PM, Scott Kozel wrote:
Anyone want to predict whether this will actually happen in 2024?
It would be interesting for sure.


I'd say improbable... Forgetting minor nits such as the lack of a lander
and lunar EVA suits...

It'll be interesting to see if they actually have a working upper stage
for Block 1 SLS, let alone reliable.

If the Delta III experience of DCSS is any indication of a forerunner
for ICPS...

"The DCSS first flew on 3 Delta IIIs, and failed 2 of 2 times. The
booster failed on the third flight, causing the loss of the DCSS before
ignitions." ..and..

"The Interim Cryogenic Propulsion Stage (ICPS), a modified 5?meter DCSS,
will fly as the upper stage of NASA's Block 1 Space Launch System.[3]
Artemis 1, the first flight, is scheduled for late 2020."

From:
https://en.wikipedia.org/wiki/Delta_...c_Second_Stage

A 2nd stage failure would certainly be basis for program delays.


In addition to having a lander and EVA suits designed and built, need
to have some recent experience in using them, including with current
astronauts.

Also need recent experience with rendezvous and docking, including with
current astronauts.


We already have that with commercial crew. Also, computers are so much
better than they were in the 60s, much of rendezvous and docking is
automated. This was demonstrated on the first, uncrewed, Dragon 2
mission to ISS. Mostly the astronauts just monitored Dragon 2 as it
approached ISS and docked.

Honestly, the equations aren't *that* hard. I know a guy who used to
help write the Rendezvous and Proximity Operations (RPOP) software for
use on laptops during the space shuttle program. That sort of software
is now built into the flight control system of new vehicles that are
designed to autonomously rendezvous and dock.


What about the effort needed to design and build a lander, and EVA suits,
and a rover, and then getting recent experience with them?

How many preparatory flights would be needed before attempting a landing?

  #15  
Old July 27th 19, 03:46 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Artemis 3 Mission in 2024

In article , says...

On 7/26/2019 2:27 AM, William Elliot wrote:

If weren't for thea Russian Sputnik, would US have a space program?


An interesting question. I would say, yes, but it would have looked very
differently from what we remember and it would have been primarily a US
Air Force program working in conjunction with the NACA.

Sputnik was inevitable, but the *real* story is that Von Braun's team
was ready to add a small 3rd kick stage to the Jupiter C rocket a year
or so *before* Sputnik, that would have put a satellite into orbit, but
Eisenhower nixed the idea. Why I'll never know. Had that been done,
likely no panic, no NASA and no moon program.

snip

One theory is that we didn't want to be accused of overflying other
countries. When Sputnik went first, from what I understand the US
didn't protest the overflight. This set the stage for orbital spy
satellites and the like.

Jeff
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  #17  
Old July 29th 19, 03:32 AM posted to sci.space.policy
Greg \(Strider\) Moore
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Default Artemis 3 Mission in 2024

"JF Mezei" wrote in message ...

What sort of different features are needed for a Moon EVA suit vs
Shuttle/Station EVA suit? Bigger boots is obvious. I take it an extra
layer for radiation shielding? What else?


No, no extra layer. Not really feasible. But better flexibility.
The current EVA suits don't bend well at the waist, nor do they need to.

The A7LB used for the final Apollo missions had extra joints at the waist
and neck to allow enough flexibility to sit in the lunar rover.

Because of the hard torso design of the current EMU suits, they'd wouldn't
be very practical on the lunar surface.
Also, I believe the current suits have no buddy system connectors.
I don't know about thermal considerations, but my guess is those would need
to change also.


for trying to prod NASA into actually doing something, but no bucks, no
Buck Rogers. They'll never get the "blank check" style funding needed
to do this program in that short amount of time.



Political stunt. Announce great but unrealistic mission to force the
next administration to be the bearer of bad news when they cancel it.


--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
IT Disaster Response -
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  #18  
Old July 29th 19, 11:42 AM posted to sci.space.policy
Jeff Findley[_6_]
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Default Artemis 3 Mission in 2024

In article ,
says...

On 2019-07-25 06:43, Jeff Findley wrote:

Zero chance. This program is a burning dumpster.


Won't SLS/Orion at the very least do a spin around the moon and back to
Earth?


It can get to a NRHO around the moon. That's why that particular orbit
was chosen for Gateway. There is lots of info about this online.

Options for Staging Orbits in Cis-Lunar Space - NTRS - NASA
https://ntrs.nasa.gov/archive/nasa/c...0150019648.pdf

Orion doesn't have the delta-V to get into a low lunar orbit and get
back to earth with the margins that NASA requires. This is doubly true
of some kind of other payload is co-mainifested with Orion on SLS.

Note that making SLS bigger (e.g. Block 2) does not help with this
problem. In fact, it makes it worse because any co-manifested payload
would necessarily be bigger, to take advantage of the extra payload
capacity of SLS Block 2.

That's why Gateway is tuck in NRHO, not something more useful like a low
polar orbit (well, close to polar, see the reference above).

Casnada signed up to help with Gateway. Curious to see what went on
behind the scenes for this. Our transport Minister if Marc Garneau,
former astronaut who flew on Shuttle. So he would have a pretty good
idea of the odds of this project.


Of course Gateway will get a robotic arm, because "that's the way we've
always done things with the shuttle and ISS". And of course Canada will
want some of its astronauts to participate if there is a chance that
they may walk on the moon.

On top of that, NASA has no lunar EVA suits.


Shirley than can ask Hollywood they can make these suits pretty quickly,
just don't check the box that says "integrated light to make astronaut's
face visible" :-)

Since the last Moon rated suits date from the 1960s, how different would
current designs be?


This is the exact *same* problem you have with "dusting off the Saturn V
plans and building new copies" only with a spacesuit. I'm not going to
enumerate the many reasons that make it hard to "just build more Apollo
EVA suits" because they're the same reasons.

What sort of different features are needed for a Moon EVA suit vs
Shuttle/Station EVA suit? Bigger boots is obvious. I take it an extra
layer for radiation shielding? What else?


For one, space shuttle era EMU suits are way to heavy for extended EVAs.
They were designed to work in microgravity, after all. They traded away
the lighter mass of the Apollo EVA suits for longevity and modularity
(which naturally came with a much heavier mass).

Jeff
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  #19  
Old July 30th 19, 12:28 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Artemis 3 Mission in 2024

In article ,
says...

On 2019-07-29 06:42, Jeff Findley wrote:

This is the exact *same* problem you have with "dusting off the Saturn V
plans and building new copies" only with a spacesuit.



I considered this before posting. However, aren't suits made by hand
anyways? Not like they need to build tooling to produce large engine
bells etc.


All the people who made the Apollo suits are don't work anymore because
they're either dead or retired.

Since they need to build new suits anyways, what is wrong with looking
to duplicate certain components (not advocating they duplicate the whole
suit down to every detail). They still need to be tested whether you
start from blank sheet or inspire yourself from either Apollo or Shuttle
EVA suits.


Same problem you have with "duplicating" anything made more than 50
years ago. You have to certify it as a new design anyway, because you
don't know what you don't know. Just because someone can make something
that looks like an Apollo suit, doesn't mean it's going to perform like
one.

Mr Strider already mentioned many of the reasons why Shuttle EVA suits
are not good for a weekend camping trip to the moon.


Yes, they won't work well at all. Even if NASA chooses to modify the
leg design for increased mobility, they still mass too much to be
practical for anything other than a very short "flags and footprints"
EVA that would necessarily be much shorter than the Apollo EVAs with
lighter, more mobile, suits.

Do Shuttle EVA suits have a much more modern/advanced ECLSS system than
Apollo era ones? If one were to build ECLSS pack from blank sheet,
would it incorporate technologies that are vastly mroe advanced than
Shuttle EVA suits or is ECLSS prtty much a mature tech and new ECLSS
would function pretty much like one from Shuttle era?


I'm not an expert, but the lessons learned from Apollo went into the
shuttle era ECLSS.

BTW, what powered the Apollo era suits? (what sort of batteries)? What
about Shuttle EVA suits? I assume new suits would use lithium batteries?


I don't know. Google it.

Mr Strider mentioned the Apollo suits evolved during the Apollo
missions. How much have the Shuttle EVA suits evolved over the 40 year
lifetime of programme?


The gloves have been updated a bit. They always have problems with the
gloves. Other than that, I'm not sure what has been updated other than
"bug fixes" for issues.

Jeff

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  #20  
Old July 31st 19, 12:47 AM posted to sci.space.policy
Greg \(Strider\) Moore
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Default Artemis 3 Mission in 2024

"JF Mezei" wrote in message ...

On 2019-07-30 07:28, Jeff Findley wrote:

All the people who made the Apollo suits are don't work anymore because
they're either dead or retired.


But surely the designs are available somewhere, perhaps even at the
Smithsonian?


Yes, but again, the skills necessary to actually MAKE them may not be
available.


This is especially good f they can have the documentation on the changes
made to Apollo era suits during their short tenure as the explanation
for those changes would provide valuable insights to prevent repeating
same mistakes.



Same problem you have with "duplicating" anything made more than 50
years ago. You have to certify it as a new design anyway,


Never said they wouldn't. Whatever they make for Artemis is to be new
and need to be tested. What I am arguing is that the Apollo era
experience should be used as much as possible as it would help prevent
problems and help guide the design of new suits. Mr Strider mentioned
the number of joints etc.


And yes, of course any new designs will try to learn lessons from previous
designs.
Not sure why you're expecting otherwise.

And speaking to remaining astronauts and/or people who worked to
design/build/maintain those suits could also provide insights.

Would it be correct to state that the Apollo era suits were used only on
one mission and new suits for each mission? Were they returned to earth
or left in the LEM ?


Considering they were custom made for each astronaut, yes they were only
used once.
And since they were required for re-entry, they were returned.





Yes, they won't work well at all. Even if NASA chooses to modify the
leg design for increased mobility, they still mass too much to be
practical for anything other than a very short "flags and footprints"


Lets not kid ourselves, the SLS/Orion, if it even lands on moon will be
only flags/footprints mission.

From a materials point of view, would building new Shuttle suits with
modern materials (composite,s alloys) reduce their mass signifcantly or
just marginally? What ends up weighting most on those suits?

What made the Shuttle EVA suits so much heavier than Apollo ones?


The hard torso.

This is perhaps the fundamental difference between the Apollo A7L and A7LB
suits and the shuttle EVA suits.
The Apollo era suits were custom made for each astronaut (actually 3 per
astronaut, 1 for use, 1 for training and 1 as a backup.)

As such, they were guaranteed to fit the particular astronaut they were
built for.

For the shuttle era, NASA knew they'd be flying lots of different astronauts
and could not afford (both in time and money) developing customer suits for
each one.

So they went with a hard torso (in I think 3 sizes, S, M, L) and then soft
components for the arms and legs. These can be swapped out to fit the
particular astronaut.
Apparently an XS hard torso was considered, but there literally wasn't
enough room for all components in the original design.

I believe there are only about a dozen suits (and I believe some of the hard
torsos originate from the 80s).

So, new suits will need to be created, regardless.

That said, some of the considerations that will go into a next generation
EVA suit, especially for lunar EVA:

Better mobility. Between the original suits (A7L) for the Apollo 11-14
missions and the updated (A7LB) for the 15-17 missions, an extra waist and
neck joint were added. This added in their ability to bend and more
importantly, sit I the LRV.

Better durability. The original suits used a pair of zippers to seal them
up. Easy to operate, but apparently, by the 3rd EVAs on the later missions,
the components were starting to wear and air leakage was noticeable. One
design consideration would be to use "suit locks" where the suit itself is
basically attached to an airlock. The astronaut climbs into the back of the
suit (much like the current Russian design) and closes the backpack over the
opening and then the suit (with astronaut) detaches from its own personal
airlock. This keeps lunar dust from entering the vehicle and simplifies
cleaning and the like. But is a more complex design and I'm not sure NASA is
ready to go for that complexity. And even if they do, the astronauts would
still need a pressure suit for other portions of the flight. NASA is not
going to let them do operations like landing, takeoff, or docking without a
pressure suit.

Ideally (but unlikely) higher operating pressure. The time currently used
to reduce the pressure of the airlock so astronauts can go on EVA is 6-8
hours. This reduces available science time which is critical on the Moon.
More likely on earlier flights NASA will simply run the entire complex at a
lower pressure than ISS.

Fit 90% of all astronauts like current shuttle suits.

It's going to be a fun engineer exercise.


--
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CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
IT Disaster Response -
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