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Groups > sci.astro > #61368 > unrolled thread

Towards routine, reusable space launch.

Started by"Robert Clark" <rgregoryclark@gmSPAMBLOCKail.com>
First post2018-06-07 16:24 -0400
Last post2018-06-08 18:06 -0400
Articles 20 on this page of 87 — 13 participants

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  Towards routine, reusable space launch. "Robert Clark" <rgregoryclark@gmSPAMBLOCKail.com> - 2018-06-07 16:24 -0400
    Re: Towards routine, reusable space launch. "Robert Clark" <rgregoryclark@gmSPAMBLOCKail.com> - 2018-06-07 16:47 -0400
    Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-07 23:24 -0700
    Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-08 13:10 +0000
      Re: Towards routine, reusable space launch. Sergio <invalid@invalid.com> - 2018-06-08 08:31 -0500
      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-08 20:47 -0700
        Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-09 17:19 +0000
          Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-09 16:02 -0400
            Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-11 03:16 +0000
              Re: Towards routine, reusable space launch. Thomas Koenig <tkoenig@netcologne.de> - 2018-06-11 05:25 +0000
                Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-11 22:18 +0000
                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-11 20:52 -0700
                  Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-12 06:34 -0400
                    Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-12 14:36 +0000
                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 14:29 -0700
                      Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-12 19:00 -0400
                        Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-13 02:15 -0400
                          Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 01:27 -0700
                          Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-13 06:46 -0400
                            Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-13 16:28 -0400
                              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 14:38 -0700
                              Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-14 05:22 -0400
                                Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-14 15:44 -0400
                                  Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-15 07:52 -0400
                                    Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-15 21:33 -0400
                                      Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-16 10:38 -0400
                                        Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-16 17:51 -0400
                                          Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-17 02:16 -0700
                                            Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-17 15:49 -0400
                                              Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-17 16:52 -0400
                                                Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-18 02:44 -0400
                                                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-18 00:05 -0700
                                                    Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-18 14:27 -0400
                                                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-18 19:39 -0700
                                              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-17 18:26 -0700
                        Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-13 12:57 +0000
                          Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 14:35 -0700
                            Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-13 17:55 -0400
                              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 21:44 -0700
                              Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-14 22:02 +0000
                            Re: Towards routine, reusable space launch. Alain Fournier <alain245@videotron.ca> - 2018-06-13 19:39 -0400
                              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 21:53 -0700
                                Re: Towards routine, reusable space launch. Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2018-06-14 15:15 +0200
                                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-14 06:32 -0700
                                  Re: Towards routine, reusable space launch. mvp@web1.calweb.com (Mike Van Pelt) - 2018-06-14 22:26 +0000
                                Re: Towards routine, reusable space launch. Alain Fournier <alain245@videotron.ca> - 2018-06-14 19:46 -0400
                                  Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-15 07:56 -0400
                                    Re: Towards routine, reusable space launch. Alain Fournier <alain245@videotron.ca> - 2018-06-15 19:21 -0400
                                      Re: Towards routine, reusable space launch. JF Mezei <jfmezei.spamnot@vaxination.ca> - 2018-06-15 22:13 -0400
                                        Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-15 20:34 -0700
                                          Re: Towards routine, reusable space launch. Alain Fournier <alain245@videotron.ca> - 2018-06-16 09:54 -0400
                                          Re: Towards routine, reusable space launch. Sergio <invalid@invalid.com> - 2018-06-21 22:39 -0500
                          Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-14 04:47 -0400
              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-11 04:00 -0700
                Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-11 22:35 +0000
                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-11 20:58 -0700
                    Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-12 15:00 +0000
                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 14:36 -0700
                        Re: Towards routine, reusable space launch. Alain Fournier <alain245@videotron.ca> - 2018-06-12 20:08 -0400
                          Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 22:12 -0700
                            Re: Towards routine, reusable space launch. willner@cfa.harvard.edu (Steve Willner) - 2018-06-15 18:59 +0000
                              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-15 12:13 -0700
                                Re: Towards routine, reusable space launch. willner@cfa.harvard.edu (Steve Willner) - 2018-06-18 20:36 +0000
                                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-18 19:57 -0700
                                    Re: Towards routine, reusable space launch. willner@cfa.harvard.edu (Steve Willner) - 2018-06-25 21:17 +0000
                                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-25 15:52 -0700
              Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-11 07:49 -0400
                Re: Towards routine, reusable space launch. Thomas Koenig <tkoenig@netcologne.de> - 2018-06-11 16:36 +0000
                  Re: Towards routine, reusable space launch. Sergio <invalid@invalid.com> - 2018-06-11 14:02 -0500
                    Re: Towards routine, reusable space launch. benj <benj@nobody.net> - 2018-06-11 17:23 -0400
                      Re: Towards routine, reusable space launch. Sergio <invalid@invalid.com> - 2018-06-11 21:20 -0500
                  Re: Towards routine, reusable space launch. Greg Goss <gossg@gossg.org> - 2018-06-11 19:38 -0600
                Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-11 22:50 +0000
                  Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-11 21:03 -0700
                  Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-12 06:44 -0400
                    Re: Towards routine, reusable space launch. Sergio <invalid@invalid.com> - 2018-06-12 09:57 -0500
                      Re: Towards routine, reusable space launch. benj <benj@nobody.net> - 2018-06-12 17:52 -0400
                    Re: Towards routine, reusable space launch. Doc O'Leary  <droleary@2017usenet1.subsume.com> - 2018-06-12 15:20 +0000
                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 14:47 -0700
                    Re: Towards routine, reusable space launch. Thomas Koenig <tkoenig@netcologne.de> - 2018-06-12 19:43 +0000
                      Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 14:52 -0700
          Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-12 16:05 -0700
            Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-13 06:41 -0400
              Re: Towards routine, reusable space launch. Fred J. McCall <fjmccall@gmail.com> - 2018-06-13 14:36 -0700
      Re: Towards routine, reusable space launch. Greg Goss <gossg@gossg.org> - 2018-06-09 09:34 -0600
        Re: Towards routine, reusable space launch. Jeff Findley <jfindley@cinci.nospam.rr.com> - 2018-06-09 15:56 -0400
    Re: Towards routine, reusable space launch. "Robert Clark" <rgregoryclark@gmSPAMBLOCKail.com> - 2018-06-08 18:06 -0400

Page 4 of 5 — ← Prev page 1 2 3 [4] 5  Next page →


#61442

Fromwillner@cfa.harvard.edu (Steve Willner)
Date2018-06-15 18:59 +0000
Message-ID<pg129r$5ll$1@dont-email.me>
In reply to#61418
> >The [JWST] telescope is folded, not only the solar arrays.

In particular the 6.5-m primary mirror is folded as well as many
other pieces.  It's frightening to watch the deployment videos.

In article <cs91idhasmjd9qbdhmk4qajkgr1u3jp7fg@4ax.com>,
 Fred J. McCall <fjmccall@gmail.com> writes:
> And THAT is because you cannot make a single mirror that large to
> adequate precision,

At least three observatories with seven telescopes in active use will
be surprised to learn that.  Not to mention additional ones planned.

Every JWST presentation I've seen that mentioned the subject said
that using a deployable (folding) mirror is because the Ariane 5
shroud is too small to fit a 6.5-m mirror.  I wouldn't be surprised
if there are "black" programs with the same difficulty.

That said, this particular use case doesn't necessarily justify a
rockoon approach, which will be difficult at best for large boosters.

-- 
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 

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#61443

FromFred J. McCall <fjmccall@gmail.com>
Date2018-06-15 12:13 -0700
Message-ID<1q38id1rbuqh4k46gpk8o1m70o294nn3k8@4ax.com>
In reply to#61442
willner@cfa.harvard.edu (Steve Willner) wrote on Fri, 15 Jun 2018
18:59:07 -0000 (UTC):

>> >The [JWST] telescope is folded, not only the solar arrays.
>
>In particular the 6.5-m primary mirror is folded as well as many
>other pieces.  It's frightening to watch the deployment videos.
>
>In article <cs91idhasmjd9qbdhmk4qajkgr1u3jp7fg@4ax.com>,
> Fred J. McCall <fjmccall@gmail.com> writes:
>> And THAT is because you cannot make a single mirror that large to
>> adequate precision,
>
>At least three observatories with seven telescopes in active use will
>be surprised to learn that.  Not to mention additional ones planned.
>

You can do things with earthbound scopes that you cannot do with
something you're going to shoot into space.

>
>Every JWST presentation I've seen that mentioned the subject said
>that using a deployable (folding) mirror is because the Ariane 5
>shroud is too small to fit a 6.5-m mirror.  I wouldn't be surprised
>if there are "black" programs with the same difficulty.
>

Nope.  They use a mirror roughly the size of Hubble's.  Remember,
they're looking at something relatively close as such things go.

>
>That said, this particular use case doesn't necessarily justify a
>rockoon approach, which will be difficult at best for large boosters.
>

Yes.  The point is that a balloon does NOT replace a 'first stage'.


-- 
"The reasonable man adapts himself to the world; the unreasonable 
 man persists in trying to adapt the world to himself. Therefore, 
 all progress depends on the unreasonable man."
                                      --George Bernard Shaw

[toc] | [prev] | [next] | [standalone]


#61460

Fromwillner@cfa.harvard.edu (Steve Willner)
Date2018-06-18 20:36 +0000
Message-ID<pg954i$pce$1@dont-email.me>
In reply to#61443
> >At least three observatories with seven telescopes in active use will
> >be surprised to learn [that making a 6.5-m primary mirror is impossible]

That should have been five observatories and ten telescopes.  I
forgot some.  I won't swear I'm not still forgetting others.

In article <1q38id1rbuqh4k46gpk8o1m70o294nn3k8@4ax.com>,
 Fred J. McCall <fjmccall@gmail.com> writes:
> You can do things with earthbound scopes that you cannot do with
> something you're going to shoot into space.

How does that apply to the current discussion?  Launching a 6.5-m
mirror monolithic should in principle be easier than having the same
size mirror deploy to the required precision.  The problem is making
it fit into the payload fairing.

> >  I wouldn't be surprised if there are "black" programs with the
> >same difficulty.

> Nope.  They use a mirror roughly the size of Hubble's.

The ones we know about used mirrors that size.  Anyone who actually
knows the current situation -- I don't -- wouldn't be allowed to say.

>  Remember, they're looking at something relatively close as such
> things go.

6.5-m mirrors would have advantages over smaller ones.  (I don't see
what distance has to do with anything.)  I've seen hints that some
have been built and deployed, but that may be salemanship.  Companies
vying for the JWST contract would have had an incentive to drop such
hints whether true or not.

>  The point is that a balloon does NOT replace a 'first stage'.

We agree on that.

-- 
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 

[toc] | [prev] | [next] | [standalone]


#61462

FromFred J. McCall <fjmccall@gmail.com>
Date2018-06-18 19:57 -0700
Message-ID<2frgidh5cfamkc9f50i79cts222ho7t09j@4ax.com>
In reply to#61460
willner@cfa.harvard.edu (Steve Willner) wrote on Mon, 18 Jun 2018
20:36:35 -0000 (UTC):

>> >At least three observatories with seven telescopes in active use will
>> >be surprised to learn [that making a 6.5-m primary mirror is impossible]
>
>That should have been five observatories and ten telescopes.  I
>forgot some.  I won't swear I'm not still forgetting others.
>

And you're still talking about earthbound scopes.

>In article <1q38id1rbuqh4k46gpk8o1m70o294nn3k8@4ax.com>,
> Fred J. McCall <fjmccall@gmail.com> writes:
>> You can do things with earthbound scopes that you cannot do with
>> something you're going to shoot into space.
>
>How does that apply to the current discussion?  Launching a 6.5-m
>mirror monolithic should in principle be easier than having the same
>size mirror deploy to the required precision.  The problem is making
>it fit into the payload fairing.
>

Oversize fairings are easy.

>> >  I wouldn't be surprised if there are "black" programs with the
>> >same difficulty.
>
>> Nope.  They use a mirror roughly the size of Hubble's.
>
>The ones we know about used mirrors that size.  Anyone who actually
>knows the current situation -- I don't -- wouldn't be allowed to say.
>

Of course they're allowed to say.  You can see the bloody things from
Earth, after all.  Past a certain point a bigger mirror doesn't help
you for Earth observation.  Atmosphere speckle becomes the driving
parameter and a bigger mirror doesn't help that.

>
>>
>>  Remember, they're looking at something relatively close as such
>> things go.
>>
>
>6.5-m mirrors would have advantages over smaller ones. 
>

No, they wouldn't.  The next generation of recce satellites will use a
mirror right around 2.4 meters; the same size used since KH-11.

>
>(I don't see
>what distance has to do with anything.)  I've seen hints that some
>have been built and deployed, but that may be salemanship.  Companies
>vying for the JWST contract would have had an incentive to drop such
>hints whether true or not.
>

Don't let them kid you.  Distance has a lot to do with everything when
it comes to telescopes.  

>>  The point is that a balloon does NOT replace a 'first stage'.
>
>We agree on that.

-- 
"The reasonable man adapts himself to the world; the unreasonable 
 man persists in trying to adapt the world to himself. Therefore, 
 all progress depends on the unreasonable man."
                                      --George Bernard Shaw

[toc] | [prev] | [next] | [standalone]


#61468

Fromwillner@cfa.harvard.edu (Steve Willner)
Date2018-06-25 21:17 +0000
Message-ID<pgrm4i$ifl$1@dont-email.me>
In reply to#61462
In article <2frgidh5cfamkc9f50i79cts222ho7t09j@4ax.com>,
 Fred J. McCall <fjmccall@gmail.com> writes:
> Oversize fairings are easy.

No doubt the JWST engineers wish you had told them that.

>>[mirror size of reconnaissance satellites]

> You can see the bloody things from Earth, after all.

See some of them, sure.  Why do you think the census is complete?
What observations (equipment) are needed to measure their sizes?

>  Past a certain point a bigger mirror doesn't help
> you for Earth observation.  Atmosphere speckle becomes the driving
> parameter and a bigger mirror doesn't help that.

Are you assuming LEO and visible wavelengths?  I don't see why either
one necessarily represents all reconnaissance satellites.  And even
with those assumptions, what about temporal resolution?  Taking short
exposures most certainly helps mitigate seeing effects.
("Atmospheric speckle" is only one of those effects.)

> No, they wouldn't.  The next generation of recce satellites will use a
> mirror right around 2.4 meters; the same size used since KH-11.

Source?  All of them or only some?  Other than better sensors and
onboard processing, how do newer telescopes differ from the older
generation?  (As you no doubt know but some readers may not, two of
those were declared surplus and delivered to NASA.)

>   Distance has a lot to do with everything when
> it comes to telescopes. 

What did you have in mind?  I'd have said the key parameters are
angular resolution, temporal resolution, and sensitivity.  Distance
affects requirements on those parameters, but I don't see that
distance _per se_ matters.

-- 
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner            Phone 617-495-7123     swillner@cfa.harvard.edu
Cambridge, MA 02138 USA                 

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#61469

FromFred J. McCall <fjmccall@gmail.com>
Date2018-06-25 15:52 -0700
Message-ID<err2jdtgfa6qocdehli253go6kmerapq9k@4ax.com>
In reply to#61468
willner@cfa.harvard.edu (Steve Willner) wrote on Mon, 25 Jun 2018
21:17:06 -0000 (UTC):

>In article <2frgidh5cfamkc9f50i79cts222ho7t09j@4ax.com>,
> Fred J. McCall <fjmccall@gmail.com> writes:
>> Oversize fairings are easy.
>
>No doubt the JWST engineers wish you had told them that.
>

Well, someone should have if mirror size alone was the reason for
making it folding.

>>>[mirror size of reconnaissance satellites]
>
>> You can see the bloody things from Earth, after all.
>
>See some of them, sure.  Why do you think the census is complete?
>What observations (equipment) are needed to measure their sizes?
>

What do you think they hide them behind?  I think it's complete
because lots of people put lots of effort into it.  And it takes a
telescope and some time to measure their size.  This may be rocket
science, but it's EASY rocket science.

>>  Past a certain point a bigger mirror doesn't help
>> you for Earth observation.  Atmosphere speckle becomes the driving
>> parameter and a bigger mirror doesn't help that.
>
>Are you assuming LEO and visible wavelengths?  I don't see why either
>one necessarily represents all reconnaissance satellites.  And even
>with those assumptions, what about temporal resolution?  Taking short
>exposures most certainly helps mitigate seeing effects.
>("Atmospheric speckle" is only one of those effects.)
>

You can only 'mitigate' so far.  Are you one of those people who
believes the movies that you can make out faces from orbit and that
you can 'improve' an image with processing beyond the information that
it contains?

>> No, they wouldn't.  The next generation of recce satellites will use a
>> mirror right around 2.4 meters; the same size used since KH-11.
>
>Source?  All of them or only some?  Other than better sensors and
>onboard processing, how do newer telescopes differ from the older
>generation?  (As you no doubt know but some readers may not, two of
>those were declared surplus and delivered to NASA.)
>

Sources aren't hard to find.  Here's one.

https://spaceflightnow.com/2015/05/01/next-round-of-u-s-optical-spy-satellites-to-start-launching-in-2018/

>>   Distance has a lot to do with everything when
>> it comes to telescopes. 
>
>What did you have in mind?  I'd have said the key parameters are
>angular resolution, temporal resolution, and sensitivity.  Distance
>affects requirements on those parameters, but I don't see that
>distance _per se_ matters.
>

'Temporal resolution' is difficult, given that both the satellite and
the Earth's surface are moving relatively rapidly with regard to each
other.  Increased sensitivity means increased image noise.  Distance
matters.  That's why as newer satellites launch the older ones are
moved to lower orbits.


-- 
"The reasonable man adapts himself to the world; the unreasonable 
 man persists in trying to adapt the world to himself. Therefore, 
 all progress depends on the unreasonable man."
                                      --George Bernard Shaw

[toc] | [prev] | [next] | [standalone]


#61390

FromJeff Findley <jfindley@cinci.nospam.rr.com>
Date2018-06-11 07:49 -0400
Message-ID<MPG.35882bbe599c0062989aca@news.eternal-september.org>
In reply to#61387
In article <pfkpim$sa0$1@dont-email.me>, droleary@
2017usenet1.subsume.com says...
> For your reference, records indicate that 
> Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
> 
> > High altitude balloon launch is a tad risky and only gains you a bit of 
> > altitude and zero velocity.  Not worth the complexity and cost, IMHO.
> 
> Like I said, it might not *currently* be viable, but as an alternative 
> technology it brings new sets of trade-offs to the table such that a few 
> tweaks here and there might make it viable for certain kinds of launches 
> (e.g., ?bulky? items that are hard to make aerodynamically efficient 
> benefit from starting at the highest possible altitude).

Balloon launch isn't worth the trades which have to be made, IMHO.
 
> > BFR/BFS is planned to be "zero waste" from the very beginning.  Fully 
> > reusable TSTO with "gas and go" like operations. 
> 
> But that?s not the true ?zero waste? I was talking about.  Any resources 
> that you?re sending up *and* down, along with any fuels you burn to do it 
> safely, is a waste.  It may be a necessary waste for the current launch 
> technologies, so it?s good to minimize it, but I still say it?s a good 
> idea to think about ways to shoot stuff into space that doesn?t involve a 
> lot of heavy stuff coming back to Earth.
 
By your definition, a passenger carrying aircraft is "waste" because it 
flies from one destination to another while carrying passengers.  But 
that sort of "waste" is absolutely not a metric to optimize.  Passengers 
are buying the cheapest ticket for the flight that gets them to their 
destination.  They don't give a rat's ass about the "waste" of the 
actual aircraft having to fly there and back.

Back to space launch.  We're nowhere near the minimum cost per kg 
payload to orbit with chemical launch vehicles.  Propellant costs are 
currently less than 1% of launch costs, even for SpaceX.  

Any "waste" of propellant that allows full reuse of hardware is 
currently worth the investment.  When your hardware costs more than two 
orders of magnitude more than your propellant does, it makes a hell of a 
lot of sense to "expend" a bit of propellant to get your expensive 
hardware back intact.

When faced with an optimization problem, you look for the biggest "bang 
for the buck" bits to optimize.  Propellant "waste" is *not* that, not 
by a couple orders of magnitude.  Also, your launch hardware is a 
precious commodity, so it makes all the sense in the world to recover it 
and use it multiple times, just like a passenger carrying jet aircraft.

Jeff
-- 
All opinions posted by me on Usenet News are mine, and mine alone.  
These posts do not reflect the opinions of my family, friends, 
employer, or any organization that I am a member of.

[toc] | [prev] | [next] | [standalone]


#61391

FromThomas Koenig <tkoenig@netcologne.de>
Date2018-06-11 16:36 +0000
Message-ID<pfm8f1$ad9$1@newsreader5.netcologne.de>
In reply to#61390
Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:

> By your definition, a passenger carrying aircraft is "waste" because it 
> flies from one destination to another while carrying passengers.

Of course.

Firing passengers from large-caliber guns generates much less waste,
obviously, and should be the preferred solution :-)

[toc] | [prev] | [next] | [standalone]


#61392

FromSergio <invalid@invalid.com>
Date2018-06-11 14:02 -0500
Message-ID<pfmgvk$1b3d$1@gioia.aioe.org>
In reply to#61391
On 6/11/2018 11:36 AM, Thomas Koenig wrote:
> Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:
> 
>> By your definition, a passenger carrying aircraft is "waste" because it 
>> flies from one destination to another while carrying passengers.
> 
> Of course.
> 
> Firing passengers from large-caliber guns generates much less waste,
> obviously, and should be the preferred solution :-)
> 

perhaps the passengers should walk.

[toc] | [prev] | [next] | [standalone]


#61393

Frombenj <benj@nobody.net>
Date2018-06-11 17:23 -0400
Message-ID<ZKBTC.220840$o43.69663@fx33.iad>
In reply to#61392
On 6/11/2018 3:02 PM, Sergio wrote:
> On 6/11/2018 11:36 AM, Thomas Koenig wrote:
>> Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:
>>
>>> By your definition, a passenger carrying aircraft is "waste" because it
>>> flies from one destination to another while carrying passengers.
>>
>> Of course.
>>
>> Firing passengers from large-caliber guns generates much less waste,
>> obviously, and should be the preferred solution :-)
>>
> 
> perhaps the passengers should walk.
> 
Correct me if I'm wrong, Sergio, But then they would be
"pedestrians" rather than passengers, right?

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#61399

FromSergio <invalid@invalid.com>
Date2018-06-11 21:20 -0500
Message-ID<pfnal2$ihi$1@gioia.aioe.org>
In reply to#61393
On 6/11/2018 4:23 PM, benj wrote:
> On 6/11/2018 3:02 PM, Sergio wrote:
>> On 6/11/2018 11:36 AM, Thomas Koenig wrote:
>>> Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:
>>>
>>>> By your definition, a passenger carrying aircraft is "waste" because it
>>>> flies from one destination to another while carrying passengers.
>>>
>>> Of course.
>>>
>>> Firing passengers from large-caliber guns generates much less waste,
>>> obviously, and should be the preferred solution :-)
>>>
>>
>> perhaps the passengers should walk.
>>
> Correct me if I'm wrong, Sergio, But then they would be
> "pedestrians" rather than passengers, right?

you are right, again.
Unless you consider them as "shoe" passengers, ugh.

or if they were bundled together, like a tour group

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#61398

FromGreg Goss <gossg@gossg.org>
Date2018-06-11 19:38 -0600
Message-ID<fo8mi9Fr0h9U1@mid.individual.net>
In reply to#61391
Thomas Koenig <tkoenig@netcologne.de> wrote:

>Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:
>
>> By your definition, a passenger carrying aircraft is "waste" because it 
>> flies from one destination to another while carrying passengers.
>
>Of course.
>
>Firing passengers from large-caliber guns generates much less waste,
>obviously, and should be the preferred solution :-)

Bobble tech doesn't bother with the guns.  Just encapsulate then blow
a nuke nearby.
-- 
We are geeks.  Resistance is voltage over current.

[toc] | [prev] | [next] | [standalone]


#61396

FromDoc O'Leary <droleary@2017usenet1.subsume.com>
Date2018-06-11 22:50 +0000
Message-ID<pfmubd$62p$1@dont-email.me>
In reply to#61390
For your reference, records indicate that 
Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:

> Balloon launch isn't worth the trades which have to be made, IMHO.

Certainly not today, no, or people would be doing it.  But as I keep 
saying, new technologies keep popping up all the time that might make 
it viable in the future, at least for a few use cases.

> By your definition, a passenger carrying aircraft is "waste" because it 
> flies from one destination to another while carrying passengers.

Yes; that is true by any definition.  Just because it’s (arguably) the 
least wasteful mode of transportation we currently have says nothing 
about how we might travel in the future.

> They don't give a rat's ass about the "waste" of the 
> actual aircraft having to fly there and back.

That same logic could have been used regarding ship or train travel 
prior to the airplane’s dominance.  The point being that they *will* 
care as soon as a new technology comes along that allows more 
efficient travel.  What that might be in reality is unknown, but 
clearly something like teleportation or Futurama-style tubes are 
sci-fi ways of moving just the bits that need to be moved from one 
location to another.

> When your hardware costs more than two 
> orders of magnitude more than your propellant does, it makes a hell of a 
> lot of sense to "expend" a bit of propellant to get your expensive 
> hardware back intact.

Yes.  And I’m just wondering why you can’t just take the next step and 
admit that eliminating that expensive hardware *completely* would 
represent a cost saving of two orders of magnitude!  You wrote it, but 
it’s like you weren’t really thinking about what your words actually 
meant.

-- 
"Also . . . I can kill you with my brain."
River Tam, Trash, Firefly

[toc] | [prev] | [next] | [standalone]


#61402

FromFred J. McCall <fjmccall@gmail.com>
Date2018-06-11 21:03 -0700
Message-ID<a7huhd110t3tgdov1fm4vlv5mnhjkn26uq@4ax.com>
In reply to#61396
Doc O'Leary  <droleary@2017usenet1.subsume.com> wrote on Mon, 11 Jun
2018 22:50:22 -0000 (UTC):

>For your reference, records indicate that 
>Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
>>
>> Balloon launch isn't worth the trades which have to be made, IMHO.
>>
>
>Certainly not today, no, or people would be doing it.  But as I keep 
>saying, new technologies keep popping up all the time that might make 
>it viable in the future, at least for a few use cases.
>

Certainly not tomorrow or the next day, either.  Just what are these
magical "new technologies" that keep "popping up all the time"?

>
>>
>> By your definition, a passenger carrying aircraft is "waste" because it 
>> flies from one destination to another while carrying passengers.
>>
>
>Yes; that is true by any definition.  Just because it’s (arguably) the 
>least wasteful mode of transportation we currently have says nothing 
>about how we might travel in the future.
>

If you want to talk about "how we might travel in the future", you
need to come up with some suggestions (that aren't PFM).

>
>>
>> They don't give a rat's ass about the "waste" of the 
>> actual aircraft having to fly there and back.
>>
>
>That same logic could have been used regarding ship or train travel 
>prior to the airplane’s dominance.  
>

Nope.  Ships and trains went 'there and back', too.  Logic really
isn't your strong suit, is it?

>
>The point being that they *will* 
>care as soon as a new technology comes along that allows more 
>efficient travel.  What that might be in reality is unknown, but 
>clearly something like teleportation or Futurama-style tubes are 
>sci-fi ways of moving just the bits that need to be moved from one 
>location to another.
>

In other words, you're postulating some unspecified 'magic'.  You're
posting into the wrong newsgroup.  See the 'sci' at the front?  That
means SCIENCE.  That means you can't just wave your arms and fly to
the Moon.  You have to actually put forward the scientific basis for
why you can do so.

>
>>
>> When your hardware costs more than two 
>> orders of magnitude more than your propellant does, it makes a hell of a 
>> lot of sense to "expend" a bit of propellant to get your expensive 
>> hardware back intact.
>>
>
>Yes.  And I’m just wondering why you can’t just take the next step and 
>admit that eliminating that expensive hardware *completely* would 
>represent a cost saving of two orders of magnitude!  You wrote it, but 
>it’s like you weren’t really thinking about what your words actually 
>meant.
>

Because this is a SCIENCE newsgroup, you twat!  Yes, magic would be
nice.  We don't have it and never will.  Get over it.


-- 
"Ordinarily he is insane. But he has lucid moments when he is
 only stupid."
                            -- Heinrich Heine 

[toc] | [prev] | [next] | [standalone]


#61404

FromJeff Findley <jfindley@cinci.nospam.rr.com>
Date2018-06-12 06:44 -0400
Message-ID<MPG.35896e274b8718a3989acd@news.eternal-september.org>
In reply to#61396
In article <pfmubd$62p$1@dont-email.me>, droleary@
2017usenet1.subsume.com says...
> 
> For your reference, records indicate that 
> Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
> 
> > Balloon launch isn't worth the trades which have to be made, IMHO.
> 
> Certainly not today, no, or people would be doing it.  But as I keep 
> saying, new technologies keep popping up all the time that might make 
> it viable in the future, at least for a few use cases.

I have an engineering degree.  When developing new things, engineers 
work with what they have today because they've got schedules and 
deadlines to meet.  You're talking about technologies not yet invented.  
That's research, not development.  The two are not the same.

> > By your definition, a passenger carrying aircraft is "waste" because it 
> > flies from one destination to another while carrying passengers.
> 
> Yes; that is true by any definition.  Just because it?s (arguably) the 
> least wasteful mode of transportation we currently have says nothing 
> about how we might travel in the future.

Again, to an engineer the future is what you can do with existing tech.  
SpaceX has reduced launch costs beyond what any of the competition can 
deliver.  They arguably didn't use any new technology at all.  DC-X 
proved VTVL as a viable take of and landing mode.  SpaceX applied that 
to Falcon 9's first stage.  
 
> > They don't give a rat's ass about the "waste" of the 
> > actual aircraft having to fly there and back.
> 
> That same logic could have been used regarding ship or train travel 
> prior to the airplane?s dominance.  The point being that they *will* 
> care as soon as a new technology comes along that allows more 
> efficient travel.  What that might be in reality is unknown, but 
> clearly something like teleportation or Futurama-style tubes are 
> sci-fi ways of moving just the bits that need to be moved from one 
> location to another.

Actually moving freight by rail is the cheapest way to move a ton of 
goods from point a to point b, assuming you can connect the two by rail.  
Aircraft have the advantage of speed, so your Amazon order gets there 
overnight instead of in a week or two, but you're paying for Amazon 
Prime, which isn't exactly cheap now is it?

Two different sets of requirements lead to two completely different 
vehicles.  That's how engineering optimization works.

> > When your hardware costs more than two 
> > orders of magnitude more than your propellant does, it makes a hell of a 
> > lot of sense to "expend" a bit of propellant to get your expensive 
> > hardware back intact.
> 
> Yes.  And I?m just wondering why you can?t just take the next step and 
> admit that eliminating that expensive hardware *completely* would 
> represent a cost saving of two orders of magnitude!  You wrote it, but 
> it?s like you weren?t really thinking about what your words actually 
> meant.

As an engineer I quite simply can't do that.  There is no *proven* 
existing tech that is cheaper than liquid fueled rocket engines for 
reaching orbit.  

What you are trying to get me to admit is that eventually, some day, 
there may be something better.  Sure, there might.  Also, monkeys might 
fly out of my butt.  I'm not waiting for sci-fi to become reality.  I'm 
working with what I've got today.  Again, that's what engineers do. 

Jeff

-- 
All opinions posted by me on Usenet News are mine, and mine alone.  
These posts do not reflect the opinions of my family, friends, 
employer, or any organization that I am a member of.

[toc] | [prev] | [next] | [standalone]


#61406

FromSergio <invalid@invalid.com>
Date2018-06-12 09:57 -0500
Message-ID<pfon17$upc$2@gioia.aioe.org>
In reply to#61404
On 6/12/2018 5:44 AM, Jeff Findley wrote:
> In article <pfmubd$62p$1@dont-email.me>, droleary@
> 2017usenet1.subsume.com says...
>>
>> For your reference, records indicate that 
>> Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
>>
>>> Balloon launch isn't worth the trades which have to be made, IMHO.
>>
>> Certainly not today, no, or people would be doing it.  But as I keep 
>> saying, new technologies keep popping up all the time that might make 
>> it viable in the future, at least for a few use cases.
> 
> I have an engineering degree.  When developing new things, engineers 
> work with what they have today because they've got schedules and 
> deadlines to meet.  You're talking about technologies not yet invented.  
> That's research, not development.  The two are not the same.
> 
>>> By your definition, a passenger carrying aircraft is "waste" because it 
>>> flies from one destination to another while carrying passengers.
>>
>> Yes; that is true by any definition.  Just because it?s (arguably) the 
>> least wasteful mode of transportation we currently have says nothing 
>> about how we might travel in the future.
> 
> Again, to an engineer the future is what you can do with existing tech.  
> SpaceX has reduced launch costs beyond what any of the competition can 
> deliver.  They arguably didn't use any new technology at all.  DC-X 
> proved VTVL as a viable take of and landing mode.  SpaceX applied that 
> to Falcon 9's first stage.  
>  
>>> They don't give a rat's ass about the "waste" of the 
>>> actual aircraft having to fly there and back.
>>
>> That same logic could have been used regarding ship or train travel 
>> prior to the airplane?s dominance.  The point being that they *will* 
>> care as soon as a new technology comes along that allows more 
>> efficient travel.  What that might be in reality is unknown, but 
>> clearly something like teleportation or Futurama-style tubes are 
>> sci-fi ways of moving just the bits that need to be moved from one 
>> location to another.
> 
> Actually moving freight by rail is the cheapest way to move a ton of 
> goods from point a to point b, assuming you can connect the two by rail.  
> Aircraft have the advantage of speed, so your Amazon order gets there 
> overnight instead of in a week or two, but you're paying for Amazon 
> Prime, which isn't exactly cheap now is it?
> 
> Two different sets of requirements lead to two completely different 
> vehicles.  That's how engineering optimization works.
> 
>>> When your hardware costs more than two 
>>> orders of magnitude more than your propellant does, it makes a hell of a 
>>> lot of sense to "expend" a bit of propellant to get your expensive 
>>> hardware back intact.
>>
>> Yes.  And I?m just wondering why you can?t just take the next step and 
>> admit that eliminating that expensive hardware *completely* would 
>> represent a cost saving of two orders of magnitude!  You wrote it, but 
>> it?s like you weren?t really thinking about what your words actually 
>> meant.
> 
> As an engineer I quite simply can't do that.  There is no *proven* 
> existing tech that is cheaper than liquid fueled rocket engines for 
> reaching orbit.  
> 
> What you are trying to get me to admit is that eventually, some day, 
> there may be something better.  Sure, there might.  Also, monkeys might 
> fly out of my butt.  I'm not waiting for sci-fi to become reality.  I'm 
> working with what I've got today.  Again, that's what engineers do. 
> 
> Jeff
> 

laws of physics do not change, and they constrain possable solutions,
engineers make stuff real, and that stuff complies with physical laws.

[toc] | [prev] | [next] | [standalone]


#61413

Frombenj <benj@nobody.net>
Date2018-06-12 17:52 -0400
Message-ID<hgXTC.307363$LR2.175833@fx41.iad>
In reply to#61406
On 6/12/2018 10:57 AM, Sergio wrote:
> On 6/12/2018 5:44 AM, Jeff Findley wrote:
>> In article <pfmubd$62p$1@dont-email.me>, droleary@
>> 2017usenet1.subsume.com says...
>>>
>>> For your reference, records indicate that
>>> Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
>>>
>>>> Balloon launch isn't worth the trades which have to be made, IMHO.
>>>
>>> Certainly not today, no, or people would be doing it.  But as I keep
>>> saying, new technologies keep popping up all the time that might make
>>> it viable in the future, at least for a few use cases.
>>
>> I have an engineering degree.  When developing new things, engineers
>> work with what they have today because they've got schedules and
>> deadlines to meet.  You're talking about technologies not yet invented.
>> That's research, not development.  The two are not the same.
>>
>>>> By your definition, a passenger carrying aircraft is "waste" because it
>>>> flies from one destination to another while carrying passengers.
>>>
>>> Yes; that is true by any definition.  Just because it?s (arguably) the
>>> least wasteful mode of transportation we currently have says nothing
>>> about how we might travel in the future.
>>
>> Again, to an engineer the future is what you can do with existing tech.
>> SpaceX has reduced launch costs beyond what any of the competition can
>> deliver.  They arguably didn't use any new technology at all.  DC-X
>> proved VTVL as a viable take of and landing mode.  SpaceX applied that
>> to Falcon 9's first stage.
>>   
>>>> They don't give a rat's ass about the "waste" of the
>>>> actual aircraft having to fly there and back.
>>>
>>> That same logic could have been used regarding ship or train travel
>>> prior to the airplane?s dominance.  The point being that they *will*
>>> care as soon as a new technology comes along that allows more
>>> efficient travel.  What that might be in reality is unknown, but
>>> clearly something like teleportation or Futurama-style tubes are
>>> sci-fi ways of moving just the bits that need to be moved from one
>>> location to another.
>>
>> Actually moving freight by rail is the cheapest way to move a ton of
>> goods from point a to point b, assuming you can connect the two by rail.
>> Aircraft have the advantage of speed, so your Amazon order gets there
>> overnight instead of in a week or two, but you're paying for Amazon
>> Prime, which isn't exactly cheap now is it?
>>
>> Two different sets of requirements lead to two completely different
>> vehicles.  That's how engineering optimization works.
>>
>>>> When your hardware costs more than two
>>>> orders of magnitude more than your propellant does, it makes a hell of a
>>>> lot of sense to "expend" a bit of propellant to get your expensive
>>>> hardware back intact.
>>>
>>> Yes.  And I?m just wondering why you can?t just take the next step and
>>> admit that eliminating that expensive hardware *completely* would
>>> represent a cost saving of two orders of magnitude!  You wrote it, but
>>> it?s like you weren?t really thinking about what your words actually
>>> meant.
>>
>> As an engineer I quite simply can't do that.  There is no *proven*
>> existing tech that is cheaper than liquid fueled rocket engines for
>> reaching orbit.
>>
>> What you are trying to get me to admit is that eventually, some day,
>> there may be something better.  Sure, there might.  Also, monkeys might
>> fly out of my butt.  I'm not waiting for sci-fi to become reality.  I'm
>> working with what I've got today.  Again, that's what engineers do.
>>
>> Jeff
>>
> 
> laws of physics do not change, and they constrain possable solutions,
> engineers make stuff real, and that stuff complies with physical laws.
> 
Actually the laws of physics DO CHANGE as they are only the 
understanding of humans and their current interpretation of what they 
perceive as reality. What you mean to say is that fundamental 
relationships governing physical phenomena do not change even if we 
don't quite know what they are.

And what Jeff meant to say is that there is no "publicly known" 
technology cheaper than rockets for reaching orbit. Not quite the same 
thing as no "proven" technology.

And as for "some day" such things can be important such as trying to 
find a workable alternative to fossil fuels which are certain to run 
out. The "green" idea of a return to the ox carts and the middle ages 
does not seem to be a way to lock in the the current advances of our 
civilization, does it?

[toc] | [prev] | [next] | [standalone]


#61408

FromDoc O'Leary <droleary@2017usenet1.subsume.com>
Date2018-06-12 15:20 +0000
Message-ID<pfoobm$hm7$1@dont-email.me>
In reply to#61404
For your reference, records indicate that 
Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:

> I have an engineering degree.  When developing new things, engineers 
> work with what they have today because they've got schedules and 
> deadlines to meet.  You're talking about technologies not yet invented.  
> That's research, not development.  The two are not the same.

I never claimed they were.  The topic of the thread is *not* “what can 
I build today”, it’s “Towards routine, reusable space launch.”  That 
has nothing to do with today’s technology, and nobody has made the 
case that continued use of rockets (even reusable ones) can make it 
happen.

> Two different sets of requirements lead to two completely different 
> vehicles.  That's how engineering optimization works.

Indeed.  Which is why I argue that rockets alone are unlikely to be the 
only path to space.  And they *definitely* are not the path to deep 
space.

> What you are trying to get me to admit is that eventually, some day, 
> there may be something better.  Sure, there might.  Also, monkeys might 
> fly out of my butt.

Really?  You think new technologies are butt-monkeys unlikely?  Then 
let’s get you retired, man, because you are *not* allowing your field 
to innovate nearly as much as it needs to.

> I'm not waiting for sci-fi to become reality.  I'm 
> working with what I've got today.  Again, that's what engineers do. 

Then you should be looking in engineering newsgroups for that kind of 
discussion.  Science is about more than just using your current tools.

-- 
"Also . . . I can kill you with my brain."
River Tam, Trash, Firefly

[toc] | [prev] | [next] | [standalone]


#61412

FromFred J. McCall <fjmccall@gmail.com>
Date2018-06-12 14:47 -0700
Message-ID<o6f0id9pp12elv3g417lcdip54v9p0bhpf@4ax.com>
In reply to#61408
Doc O'Leary  <droleary@2017usenet1.subsume.com> wrote on Tue, 12 Jun
2018 15:20:22 -0000 (UTC):

>For your reference, records indicate that 
>Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
>>
>> I have an engineering degree.  When developing new things, engineers 
>> work with what they have today because they've got schedules and 
>> deadlines to meet.  You're talking about technologies not yet invented.  
>> That's research, not development.  The two are not the same.
>>
>
>I never claimed they were.  
>

Actually you are, but you're too thick to recognize the implications
of your position.

>
>The topic of the thread is *not* “what can 
>I build today”, it’s “Towards routine, reusable space launch.”  That 
>has nothing to do with today’s technology, and nobody has made the 
>case that continued use of rockets (even reusable ones) can make it 
>happen.
>

You're not going to move "towards routine, reusable space launch" with
technologies that you CANNOT build today and that you cannot even
describe a scientific theoretical basis for.  It has EVERYTHING to do
with today's technology and if you think there's something other than
rockets, either trot it out or STFU.

>
>>
>> Two different sets of requirements lead to two completely different 
>> vehicles.  That's how engineering optimization works.
>>
>
>Indeed.  Which is why I argue that rockets alone are unlikely to be the 
>only path to space.  And they *definitely* are not the path to deep 
>space.
>

Right now there IS no path to 'deep space'.  It's sad, but get over
it.

>
>>
>> What you are trying to get me to admit is that eventually, some day, 
>> there may be something better.  Sure, there might.  Also, monkeys might 
>> fly out of my butt.
>>
>
>Really?  You think new technologies are butt-monkeys unlikely?  Then 
>let’s get you retired, man, because you are *not* allowing your field 
>to innovate nearly as much as it needs to.
>

He thinks that your 'magic' technology that breaks the laws of physics
is "butt-monkeys unlikely".  I agree with him.  So does anyone sane
with any knowledge of science and engineering.

>
>>
>> I'm not waiting for sci-fi to become reality.  I'm 
>> working with what I've got today.  Again, that's what engineers do. 
>>
>
>Then you should be looking in engineering newsgroups for that kind of 
>discussion.  Science is about more than just using your current tools.
>

I don't think you know what science is.  What it is NOT is airy
speculation about 'new magic' in the sweet by and by.


-- 
"Some people get lost in thought because it's such unfamiliar
 territory."
                                      --G. Behn

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#61409

FromThomas Koenig <tkoenig@netcologne.de>
Date2018-06-12 19:43 +0000
Message-ID<pfp7o8$ttc$1@newsreader5.netcologne.de>
In reply to#61404
Jeff Findley <jfindley@cinci.nospam.rr.com> schrieb:
> In article <pfmubd$62p$1@dont-email.me>, droleary@
> 2017usenet1.subsume.com says...
>> 
>> For your reference, records indicate that 
>> Jeff Findley <jfindley@cinci.nospam.rr.com> wrote:
>> 
>> > Balloon launch isn't worth the trades which have to be made, IMHO.
>> 
>> Certainly not today, no, or people would be doing it.  But as I keep 
>> saying, new technologies keep popping up all the time that might make 
>> it viable in the future, at least for a few use cases.
>
> I have an engineering degree.

So do I (PhD in chemical engineering).

> When developing new things, engineers 
> work with what they have today because they've got schedules and 
> deadlines to meet.

The world would be a poorer place if that was the case.

> You're talking about technologies not yet invented.  
> That's research, not development.  The two are not the same.

How would you classify chemical process development?  Seems that,
according to your defiinition, I am doing more research than I
thought :-)

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