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Groups > rec.arts.sf.written > #450559
| From | Don Kuenz <g@crcomp.net> |
|---|---|
| Newsgroups | rec.arts.sf.written |
| Subject | Re: Young People Read Old SFF: Nightfall by Isaac Asimov |
| Date | 2016-09-02 04:34 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <20160901c@crcomp.net> (permalink) |
| References | (9 earlier) <nqa7mb$leh$2@dont-email.me> <20160901a@crcomp.net> <nqanku$1ag$1@dont-email.me> <20160901b@crcomp.net> <30ab5c6a-041c-4ead-96d6-69c9c0fbb442@googlegroups.com> |
hamish.laws@gmail.com wrote:
> On Friday, September 2, 2016 at 1:25:43 PM UTC+10, Don Kuenz wrote:
>> David Johnston <Davidjohnston29@yahoo.com> wrote:
>> > On 9/1/2016 6:40 PM, Don Kuenz wrote:
>> >> David Johnston <Davidjohnston29@yahoo.com> wrote:
>> >>> On 9/1/2016 3:24 PM, Michael F. Stemper wrote:
>> >>>> On 2016-09-01 15:48, tsbrueni@gmail.com wrote:
>> >>>>> Every 2050 years, on a day when all but one of the planet's 6 suns has
>> >>>>> set, a moon gets in front of that sun, leading to a multi-hour eclipse
>> >>>>> which allows the people to see a very large number of stars. The
>> >>>>> combination of the darkness and the stars drives everyone mad.
>> >>>>>
>> >>>>> How is the planet able to hang onto a satellite that is so far away
>> >>>>> that it takes 2050 years to complete an orbit?
>> >>>>
>> >>>> Thanks to a complete lack of knowledge of celestial mechanics.
>> >>>>
>> >>>
>> >>> Wait...it doesn't take 2050 years to complete an orbit. It's just 2050
>> >>> years between an eclipse that happens when all except the smallest suns
>> >>> are on the other side of the planet. Of course in order for this to
>> >>> work the planet would have to have a very small land mass.
>> >>
>> >> It's also my understanding that it takes about 2050 years for the Alpha
>> >> sun and the two distant companion pairs to simultaneously set. At that
>> >> point the Beta sun is left alone in the sky so darkness ensues when a
>> >> non-luminous planetary body eclipses Beta.
>> >
>> > I'm not sure how that's different from what I said.
>> >
>> >>
>> >> The non-luminous planet may very well eclipse Beta every day but it only
>> >> causes a black out on the planet Lagash when the other five suns are
>> >> antipodal to Saro City. An antipodal event that occurs approximately
>> >> every 2050 years.
>> >>
>> >> What if Lagash and another planet of equal size rotate about each other?
>> >> Do the celestial mechanics work any better?
>> >
>> > It doesn't change the problem that the eclipse is just not going to
>> > black out the whole planet.
>>
>> This thread finally prodded me into a re-read of the whole story.
>> Michael got it right up thread. This story requires a complete lack of
>> knowledge of celestial mechanics.
>>
>> One way to achieve "a total darkness all over" Lagash is to change the
>> story and have the red dwarf Beta eclipse Alpha and the two distant
>> companion pairs. And then have a moon eclipse Beta.
>>
>> Unfortunately, the story has the other five suns setting. It just
>> doesn't work unless you stretch "a total darkness all over" to mean that
>> Lagash eventually experiences "a total darkness all over" as each
>> longitudinal slice of the planet rotates into the total eclipse.
>>
> It's been a fair while since I read the story but is it possible that
> there's only one small landmass on the planet?
My first re-read was too fast by half. A far more careful re-read of
pertinent parts revealed this essential bit:
Beta is alone in its hemisphere and at maximum distance, at
which time the moon is invariably at minimum distance. The
eclipse that results, with the moon seven times the apparent
diameter of Beta, covers all of Lagash and lasts well over
half a day, so that no spot on the planet escapes the effects.
That's my second scenario. The one where the whole planet of Lagash
eventually experiences darkness as each longitudinal slice rotates
into the eclipse. The celestial mechanics work out after all.
It's a good thing that everything finally got settled. My _Bartlett's_
is running low on eclipse quotes. :0)
Thank you,
--
Don Kuenz KB7RPU
It was that fatal and perfidious bark,
Built in th' eclipse, and rigg'd with curses dark,
That sunk so low that sacred head of thine.
-Milton
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Young People Read Old SFF: Nightfall by Isaac Asimov jdnicoll@panix.com (James Nicoll) - 2016-08-31 19:59 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Lynn McGuire <lynnmcguire5@gmail.com> - 2016-08-31 15:54 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov news{@bestley.co.uk (Mark Bestley) - 2016-08-31 22:43 +0100
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Lynn McGuire <lynnmcguire5@gmail.com> - 2016-08-31 18:30 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-08-31 19:00 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Greg Goss <gossg@gossg.org> - 2016-09-01 03:10 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov jdnicoll@panix.com (James Nicoll) - 2016-09-01 13:41 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov jdnicoll@panix.com (James Nicoll) - 2016-09-01 03:58 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Lynn McGuire <lynnmcguire5@gmail.com> - 2016-09-01 12:37 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov ted@loft.tnolan.com (Ted Nolan <tednolan>) - 2016-09-01 18:07 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-01 11:34 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Lynn McGuire <lynnmcguire5@gmail.com> - 2016-09-01 15:15 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov tsbrueni@gmail.com - 2016-09-01 13:48 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "Michael F. Stemper" <michael.stemper@gmail.com> - 2016-09-01 16:24 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-01 15:45 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-01 15:47 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-02 00:40 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov tsbrueni@gmail.com - 2016-09-01 18:18 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-01 20:20 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-01 19:46 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-01 21:09 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Dimensional Traveler <dtravel@sonic.net> - 2016-09-01 20:47 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 03:13 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-02 03:25 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov hamish.laws@gmail.com - 2016-09-01 20:48 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-02 04:34 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Robert Woodward <robertaw@drizzle.com> - 2016-09-01 22:16 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 07:32 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 07:33 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-03 00:22 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-02 21:39 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "Brian M. Scott" <b.scott@csuohio.edu> - 2016-09-02 22:57 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 21:28 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2016-09-03 05:33 +0200
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-02 23:39 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 21:25 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Paul Colquhoun <newsposter@andor.dropbear.id.au> - 2016-09-03 18:22 +1000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-03 10:10 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-04 00:38 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov tsbrueni@gmail.com - 2016-09-03 20:23 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-03 08:31 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-03 10:14 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-03 08:25 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-03 08:31 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-02 16:21 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-02 10:39 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-02 13:17 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Jaimie Vandenbergh <jaimie@sometimes.sessile.org> - 2016-09-02 23:03 +0100
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-02 17:54 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-03 00:03 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-02 21:35 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov tsbrueni@gmail.com - 2016-09-02 16:08 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David DeLaney <daviddelaney@earthlink.net> - 2016-09-02 21:16 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov 103134.3516@compuserve.com - 2016-09-07 12:56 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Robert Carnegie <rja.carnegie@excite.com> - 2016-09-07 19:05 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "Brian M. Scott" <b.scott@csuohio.edu> - 2016-09-07 22:21 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-08 04:53 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Jaimie Vandenbergh <jaimie@sometimes.sessile.org> - 2016-09-09 00:12 +0100
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Dimensional Traveler <dtravel@sonic.net> - 2016-09-08 17:00 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Greg Goss <gossg@gossg.org> - 2016-09-08 22:36 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Jaimie Vandenbergh <jaimie@sometimes.sessile.org> - 2016-09-09 08:34 +0100
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David DeLaney <daviddelaney@earthlink.net> - 2016-09-09 04:41 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov tsbrueni@gmail.com - 2016-09-09 03:31 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Jaimie Vandenbergh <jaimie@sometimes.sessile.org> - 2016-09-09 16:36 +0100
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Peter Trei <petertrei@gmail.com> - 2016-09-09 09:11 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Joe Bernstein <joe@sfbooks.com> - 2016-09-09 09:45 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 09:52 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-09 11:18 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 10:29 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Peter Trei <petertrei@gmail.com> - 2016-09-09 12:17 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Peter Trei <petertrei@gmail.com> - 2016-09-09 12:20 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov scott@slp53.sl.home (Scott Lurndal) - 2016-09-09 19:59 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 14:14 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 14:44 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 15:35 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 16:00 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 14:34 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Robert Carnegie <rja.carnegie@excite.com> - 2016-09-09 19:19 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-10 04:40 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 08:21 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-10 07:09 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 10:49 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Dimensional Traveler <dtravel@sonic.net> - 2016-09-10 08:19 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 12:27 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Greg Goss <gossg@gossg.org> - 2016-09-10 10:47 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-10 12:49 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 17:15 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Dimensional Traveler <dtravel@sonic.net> - 2016-09-10 14:20 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-10 10:29 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 12:47 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-10 10:55 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-10 12:51 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "J. Clarke" <j.clarke.873638@gmail.com> - 2016-09-10 17:18 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-11 05:45 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Don Kuenz <g@crcomp.net> - 2016-09-12 00:06 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Robert Carnegie <rja.carnegie@excite.com> - 2016-09-10 11:22 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-10 10:33 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 14:33 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Kevrob <kevrob@my-deja.com> - 2016-09-09 15:13 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-09 16:00 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 16:08 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Cryptoengineer <treifamily@gmail.com> - 2016-09-10 10:36 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 16:06 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-09 16:10 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "Brian M. Scott" <b.scott@csuohio.edu> - 2016-09-10 12:49 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Charles Bishop <ctbishop@earthlink.net> - 2016-09-10 14:43 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov "Brian M. Scott" <b.scott@csuohio.edu> - 2016-09-10 17:57 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Tom Kratman <tomkratman@gmail.com> - 2016-09-10 20:20 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-10 20:27 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Tom Kratman <tomkratman@gmail.com> - 2016-09-11 19:51 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-11 21:16 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Tom Kratman <tomkratman@gmail.com> - 2016-09-12 18:08 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-12 19:40 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Tom Kratman <tomkratman@gmail.com> - 2016-09-14 17:31 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov TB <tsbrueni@dcn.davis.ca.us> - 2016-09-14 18:16 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-14 22:26 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-11 05:38 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Greg Goss <gossg@gossg.org> - 2016-09-12 21:55 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov 103134.3516@compuserve.com - 2016-09-16 12:06 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-11 05:30 -0700
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David Johnston <Davidjohnston29@yahoo.com> - 2016-09-02 00:12 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov David DeLaney <daviddelaney@earthlink.net> - 2016-09-02 08:53 -0500
Re: Young People Read Old SFF: Nightfall by Isaac Asimov jdnicoll@panix.com (James Nicoll) - 2016-09-02 01:33 +0000
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Greg Goss <gossg@gossg.org> - 2016-09-01 21:53 -0600
Re: Young People Read Old SFF: Nightfall by Isaac Asimov wdstarr@panix.com (William December Starr) - 2016-09-01 20:11 -0400
Re: Young People Read Old SFF: Nightfall by Isaac Asimov Quadibloc <jsavard@ecn.ab.ca> - 2016-09-02 07:50 -0700
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