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Groups > rec.arts.sf.written > #424852 > unrolled thread
| Started by | "a425couple" <a425couple@hotmail.com> |
|---|---|
| First post | 2015-10-17 14:44 -0700 |
| Last post | 2015-10-22 09:59 -0700 |
| Articles | 20 on this page of 127 — 30 participants |
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Revisit issue of growing things on Mars "a425couple" <a425couple@hotmail.com> - 2015-10-17 14:44 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-18 00:37 +0000
Re: Revisit issue of growing things on Mars Robert Carnegie <rja.carnegie@excite.com> - 2015-10-17 22:23 -0700
Re: Revisit issue of growing things on Mars Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2015-10-17 22:47 -0700
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-18 17:24 -0600
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 00:51 +0000
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-18 21:12 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 02:02 +0000
Re: Revisit issue of growing things on Mars Dimensional Traveler <dtravel@sonic.net> - 2015-10-18 20:02 -0700
Re: Revisit issue of growing things on Mars "Brian M. Scott" <b.scott@csuohio.edu> - 2015-10-18 23:34 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 04:32 +0000
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-19 11:28 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 18:44 +0000
Re: Revisit issue of growing things on Mars Robert Carnegie <rja.carnegie@excite.com> - 2015-10-20 03:05 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 04:31 +0000
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-19 16:50 -0400
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-18 23:16 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 04:34 +0000
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-19 12:25 +0800
Re: Revisit issue of growing things on Mars Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2015-10-19 01:34 -0700
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-19 01:01 -0400
Re: Revisit issue of growing things on Mars Lawrence Watt-Evans <lwe@sff.net> - 2015-10-19 01:25 -0400
Re: Revisit issue of growing things on Mars ted@loft.tnolan.com (Ted Nolan <tednolan>) - 2015-10-19 06:00 +0000
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-19 00:15 -0600
Re: Revisit issue of growing things on Mars Lawrence Watt-Evans <lwe@sff.net> - 2015-10-19 02:39 -0400
Re: Revisit issue of growing things on Mars Robert Carnegie <rja.carnegie@excite.com> - 2015-10-19 05:32 -0700
Re: Revisit issue of growing things on Mars Kevrob <kevrob@my-deja.com> - 2015-10-19 13:21 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-19 13:22 +0000
Re: Revisit issue of growing things on Mars petertrei@gmail.com - 2015-10-19 08:04 -0700
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-19 17:13 -0700
Re: Revisit issue of growing things on Mars David Johnston <David@block.net> - 2015-10-19 18:31 -0600
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-20 02:17 +0000
Re: Revisit issue of growing things on Mars David Johnston <David@block.net> - 2015-10-19 20:47 -0600
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-20 04:03 +0000
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-20 00:33 -0400
Re: Revisit issue of growing things on Mars "John F. Eldredge" <john@jfeldredge.com> - 2015-10-20 23:23 +0000
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-20 17:55 -0600
Re: Revisit issue of growing things on Mars mzenier@eskimo.com (Mark Zenier) - 2015-10-20 17:00 +0000
Re: Revisit issue of growing things on Mars Dimensional Traveler <dtravel@sonic.net> - 2015-10-20 20:38 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-21 04:06 +0000
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-21 04:09 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-21 13:19 +0000
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-21 18:17 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-21 23:31 +0000
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-21 23:22 -0400
Re: Revisit issue of growing things on Mars Dimensional Traveler <dtravel@sonic.net> - 2015-10-21 20:01 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-22 03:38 +0000
Re: Revisit issue of growing things on Mars Dimensional Traveler <dtravel@sonic.net> - 2015-10-22 17:11 -0700
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-22 17:38 -0700
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-22 22:28 -0600
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-26 23:16 -0400
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-23 14:48 +0800
Re: Revisit issue of growing things on Mars petertrei@gmail.com - 2015-10-23 08:07 -0700
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-23 15:33 +0000
Re: Revisit issue of growing things on Mars petertrei@gmail.com - 2015-10-23 10:10 -0700
Re: Revisit issue of growing things on Mars Dimensional Traveler <dtravel@sonic.net> - 2015-10-23 19:07 -0700
Re: Revisit issue of growing things on Mars Larry Moore <larry@wightman.ca> - 2015-10-24 12:56 +0000
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-24 10:57 -0500
Re: Revisit issue of growing things on Mars Anthony Frost <Vulch@vulch.org> - 2015-10-25 10:40 +0100
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-25 17:23 -0400
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-25 16:41 -0500
Re: Revisit issue of growing things on Mars Thomas Koenig <tkoenig@netcologne.de> - 2015-10-25 22:32 +0000
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-26 10:39 +0800
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-25 21:47 -0500
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-27 10:42 +0800
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-23 00:57 +0000
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-26 23:12 -0400
Re: Revisit issue of growing things on Mars David DeLaney <daviddelaney@earthlink.net> - 2015-10-28 20:33 -0500
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-19 23:33 -0400
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-20 15:00 +0800
Re: Revisit issue of growing things on Mars David Johnston <David@block.net> - 2015-10-20 01:09 -0600
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-24 05:17 -0400
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-24 10:43 -0500
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-24 13:27 -0400
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-25 10:45 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-24 16:01 +0000
Re: Revisit issue of growing things on Mars Joy Beeson <jbeeson@invalid.net.invalid> - 2015-10-24 23:16 -0300
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-26 10:41 +0800
Re: Revisit issue of growing things on Mars Bill Gill <billnews2@cox.net> - 2015-10-25 08:37 -0500
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-25 14:10 +0000
Re: Revisit issue of growing things on Mars David DeLaney <daviddelaney@earthlink.net> - 2015-10-25 09:43 -0500
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-25 11:19 -0500
Re: Revisit issue of growing things on Mars Bill Gill <billnews2@cox.net> - 2015-10-25 11:42 -0500
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-26 10:43 +0800
Re: Revisit issue of growing things on Mars Larry Moore <larry@wightman.ca> - 2015-10-25 18:18 +0000
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-25 12:54 -0600
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-25 12:07 -0400
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-25 17:32 -0400
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-25 19:49 -0400
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-26 10:47 +0800
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-26 03:52 -0600
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-27 10:44 +0800
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-19 17:10 -0700
Re: Revisit issue of growing things on Mars "J. Clarke" <j.clarke.873638@gmail.com> - 2015-10-19 22:02 -0400
Re: Revisit issue of growing things on Mars Thomas Koenig <tkoenig@netcologne.de> - 2015-10-20 05:07 +0000
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-20 01:27 -0400
Re: Revisit issue of growing things on Mars Thomas Koenig <tkoenig@netcologne.de> - 2015-10-20 21:17 +0000
Re: Revisit issue of growing things on Mars Robert Carnegie <rja.carnegie@excite.com> - 2015-10-20 03:00 -0700
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-20 11:20 -0700
Re: Revisit issue of growing things on Mars petertrei@gmail.com - 2015-10-20 11:49 -0700
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-21 03:13 -0700
Re: Revisit issue of growing things on Mars petertrei@gmail.com - 2015-10-21 08:21 -0700
Re: Revisit issue of growing things on Mars Kevrob <kevrob@my-deja.com> - 2015-10-21 17:29 -0700
Re: Revisit issue of growing things on Mars Cryptoengineer <treifamily@gmail.com> - 2015-10-21 22:05 -0500
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-26 23:03 -0400
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-27 08:37 -0400
Re: Revisit issue of growing things on Mars "Brian M. Scott" <b.scott@csuohio.edu> - 2015-10-27 19:28 -0400
Re: Revisit issue of growing things on Mars Larry Moore <larry@wightman.ca> - 2015-10-28 20:28 +0000
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-29 06:07 -0400
Re: Revisit issue of growing things on Mars Robert Bannister <robban@clubtelco.com> - 2015-10-22 09:03 +0800
Re: Revisit issue of growing things on Mars Robert Carnegie <rja.carnegie@excite.com> - 2015-10-21 21:17 -0700
Re: Revisit issue of growing things on Mars wdstarr@panix.com (William December Starr) - 2015-10-25 17:42 -0400
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-26 23:05 -0400
Re: Revisit issue of growing things on Mars mzenier@eskimo.com (Mark Zenier) - 2015-10-21 15:55 +0000
Re: Revisit issue of growing things on Mars "nuny@bid.nes" <Alien8752@gmail.com> - 2015-10-22 23:19 -0700
Re: Revisit issue of growing things on Mars David DeLaney <daviddelaney@earthlink.net> - 2015-10-24 02:16 -0500
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-24 14:33 -0700
Re: Revisit issue of growing things on Mars Bill Gill <billnews2@cox.net> - 2015-10-21 08:13 -0500
Re: Revisit issue of growing things on Mars Walter Bushell <proto@panix.com> - 2015-10-19 16:42 -0400
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-19 17:15 -0700
Re: Revisit issue of growing things on Mars "Brian M. Scott" <b.scott@csuohio.edu> - 2015-10-19 20:46 -0400
Re: Revisit issue of growing things on Mars djheydt@kithrup.com (Dorothy J Heydt) - 2015-10-20 02:18 +0000
Re: Revisit issue of growing things on Mars Quadibloc <jsavard@ecn.ab.ca> - 2015-10-20 11:15 -0700
Re: Revisit issue of growing things on Mars Greg Goss <gossg@gossg.org> - 2015-10-20 18:00 -0600
Re: Revisit issue of growing things on Mars William Vetter <mdhangton@gmail.com> - 2015-10-20 20:44 -0400
Re: Revisit issue of growing things on Mars "artyw2@yahoo.com" <artyw2@yahoo.com> - 2015-10-20 14:51 -0700
Re: Revisit issue of growing things on Mars Des <desmondkavanagh@gmail.com> - 2015-10-22 09:59 -0700
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| From | "J. Clarke" <j.clarke.873638@gmail.com> |
|---|---|
| Date | 2015-10-21 04:09 -0400 |
| Message-ID | <MPG.309112433b139234989bd1@news.eternal-september.org> |
| In reply to | #425063 |
In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... > > In article <562708a0$0$1703$742ec2ed@news.sonic.net>, > Dimensional Traveler <dtravel@sonic.net> wrote: > >On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: > >> In article <n041tp$v9u$1@dont-email.me>, > >> David Johnston <David@block.net> wrote: > >>> On 10/19/2015 6:13 PM, Quadibloc wrote: > >>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: > >>>>> In article <n01tb2$uei$1@dont-email.me>, > >>>>> William Vetter <mdhangton@gmail.com> wrote: > >>>> > >>>>>> Most people don't realize that irrigation salinates soil over the > >>>>>> course of decades as trace salts in the irrigation water are > >>>>>> concentrated, after which more irrigation water is required to flush > >>>>>> out the salts before planting. > >>>> > >>>>>> In the ancient world, this was never a problem in the Nile valley, > >>>>>> because the river would flood its banks every year to do this > >>>>>> automatically, up until the Aswan Dam was built. But it was a big deal > >>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent isn't as > >>>>>> fertile as it originally was. > >>>> > >>>>> I knew the Crescent had deteriorated over the centuries because > >>>>> of salts in the soil, the result of irrigation. I didn't realize > >>>>> perchlorates were involved. > >>>> > >>>> I don't believe he was trying to say they were - just that the same > >>> accumulation of ordinary salt that caused problems on Earth could happen > >>> with perchlorates on Mars if we thought that just washing them out with > >>> water would solve the problem. > >>>> > >>>> John Savard > >>>> > >>> > >>> Just washing out salt with water DOES work. It just takes a whole > >>> heaping lot of water. > >> > >> That drains away somewhere. If you're irrigating the soil with > >> canals full of slightly salty water, then it builds up right > >> where you're trying to grow things. > >> > >It drains away to where the perchlorate eating bacteria is I believe is > >the unstated part of the argument. > > Yup. Find your perchlorate-eating bacteria,* put them down in the > bottomlands, flood the uplands with water, and wait. > > _____ > *Mrs. Beeton never did actually say "First catch your rabbit." > Her recipe began something like "Select your rabbit, and be sure > it is young and tender." The perchlorate eating bacteria seem to be around wherever there is perchlorate and water. They aren't eating the perchlorate in the Atacama Desert for example, where concentrations can be as high as .25 percent. Note that travel through the Atacama is not the instant perchlorate death that the "Perchlorate will prevent Mars exploration" people seem to think it should be.
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| From | djheydt@kithrup.com (Dorothy J Heydt) |
|---|---|
| Date | 2015-10-21 13:19 +0000 |
| Message-ID | <nwKnoK.r4D@kithrup.com> |
| In reply to | #425068 |
In article <MPG.309112433b139234989bd1@news.eternal-september.org>, J. Clarke <j.clarke.873638@gmail.com> wrote: >In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... >> >> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, >> Dimensional Traveler <dtravel@sonic.net> wrote: >> >On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: >> >> In article <n041tp$v9u$1@dont-email.me>, >> >> David Johnston <David@block.net> wrote: >> >>> On 10/19/2015 6:13 PM, Quadibloc wrote: >> >>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: >> >>>>> In article <n01tb2$uei$1@dont-email.me>, >> >>>>> William Vetter <mdhangton@gmail.com> wrote: >> >>>> >> >>>>>> Most people don't realize that irrigation salinates soil over the >> >>>>>> course of decades as trace salts in the irrigation water are >> >>>>>> concentrated, after which more irrigation water is required to flush >> >>>>>> out the salts before planting. >> >>>> >> >>>>>> In the ancient world, this was never a problem in the Nile valley, >> >>>>>> because the river would flood its banks every year to do this >> >>>>>> automatically, up until the Aswan Dam was built. But it was a big deal >> >>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent isn't as >> >>>>>> fertile as it originally was. >> >>>> >> >>>>> I knew the Crescent had deteriorated over the centuries because >> >>>>> of salts in the soil, the result of irrigation. I didn't realize >> >>>>> perchlorates were involved. >> >>>> >> >>>> I don't believe he was trying to say they were - just that the same >> >>> accumulation of ordinary salt that caused problems on Earth could happen >> >>> with perchlorates on Mars if we thought that just washing them out with >> >>> water would solve the problem. >> >>>> >> >>>> John Savard >> >>>> >> >>> >> >>> Just washing out salt with water DOES work. It just takes a whole >> >>> heaping lot of water. >> >> >> >> That drains away somewhere. If you're irrigating the soil with >> >> canals full of slightly salty water, then it builds up right >> >> where you're trying to grow things. >> >> >> >It drains away to where the perchlorate eating bacteria is I believe is >> >the unstated part of the argument. >> >> Yup. Find your perchlorate-eating bacteria,* put them down in the >> bottomlands, flood the uplands with water, and wait. >> >> _____ >> *Mrs. Beeton never did actually say "First catch your rabbit." >> Her recipe began something like "Select your rabbit, and be sure >> it is young and tender." > >The perchlorate eating bacteria seem to be around wherever there is >perchlorate and water. They aren't eating the perchlorate in the >Atacama Desert for example, where concentrations can be as high as .25 >percent. > >Note that travel through the Atacama is not the instant perchlorate >death that the "Perchlorate will prevent Mars exploration" people seem >to think it should be. Well, no, as long as the human explorers stay inside their spacesits and clean off thoroughly before entering the habitat. But we're talking about trying to terraform the place. -- Dorothy J. Heydt Vallejo, California djheydt at gmail dot com
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| From | "J. Clarke" <j.clarke.873638@gmail.com> |
|---|---|
| Date | 2015-10-21 18:17 -0400 |
| Message-ID | <MPG.3091d91fe0aa423c989bd3@news.eternal-september.org> |
| In reply to | #425073 |
In article <nwKnoK.r4D@kithrup.com>, djheydt@kithrup.com says... > > In article <MPG.309112433b139234989bd1@news.eternal-september.org>, > J. Clarke <j.clarke.873638@gmail.com> wrote: > >In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... > >> > >> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, > >> Dimensional Traveler <dtravel@sonic.net> wrote: > >> >On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: > >> >> In article <n041tp$v9u$1@dont-email.me>, > >> >> David Johnston <David@block.net> wrote: > >> >>> On 10/19/2015 6:13 PM, Quadibloc wrote: > >> >>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: > >> >>>>> In article <n01tb2$uei$1@dont-email.me>, > >> >>>>> William Vetter <mdhangton@gmail.com> wrote: > >> >>>> > >> >>>>>> Most people don't realize that irrigation salinates soil over the > >> >>>>>> course of decades as trace salts in the irrigation water are > >> >>>>>> concentrated, after which more irrigation water is required to flush > >> >>>>>> out the salts before planting. > >> >>>> > >> >>>>>> In the ancient world, this was never a problem in the Nile valley, > >> >>>>>> because the river would flood its banks every year to do this > >> >>>>>> automatically, up until the Aswan Dam was built. But it was a big deal > >> >>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent isn't as > >> >>>>>> fertile as it originally was. > >> >>>> > >> >>>>> I knew the Crescent had deteriorated over the centuries because > >> >>>>> of salts in the soil, the result of irrigation. I didn't realize > >> >>>>> perchlorates were involved. > >> >>>> > >> >>>> I don't believe he was trying to say they were - just that the same > >> >>> accumulation of ordinary salt that caused problems on Earth could happen > >> >>> with perchlorates on Mars if we thought that just washing them out with > >> >>> water would solve the problem. > >> >>>> > >> >>>> John Savard > >> >>>> > >> >>> > >> >>> Just washing out salt with water DOES work. It just takes a whole > >> >>> heaping lot of water. > >> >> > >> >> That drains away somewhere. If you're irrigating the soil with > >> >> canals full of slightly salty water, then it builds up right > >> >> where you're trying to grow things. > >> >> > >> >It drains away to where the perchlorate eating bacteria is I believe is > >> >the unstated part of the argument. > >> > >> Yup. Find your perchlorate-eating bacteria,* put them down in the > >> bottomlands, flood the uplands with water, and wait. > >> > >> _____ > >> *Mrs. Beeton never did actually say "First catch your rabbit." > >> Her recipe began something like "Select your rabbit, and be sure > >> it is young and tender." > > > >The perchlorate eating bacteria seem to be around wherever there is > >perchlorate and water. They aren't eating the perchlorate in the > >Atacama Desert for example, where concentrations can be as high as .25 > >percent. > > > >Note that travel through the Atacama is not the instant perchlorate > >death that the "Perchlorate will prevent Mars exploration" people seem > >to think it should be. > > Well, no, as long as the human explorers stay inside their > spacesits and clean off thoroughly before entering the habitat. > But we're talking about trying to terraform the place. Friend of mine spent a good bit of time in the Atacama. No spacesuit in sight. And he's far from dead.
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| From | djheydt@kithrup.com (Dorothy J Heydt) |
|---|---|
| Date | 2015-10-21 23:31 +0000 |
| Message-ID | <nwLG0v.6sL@kithrup.com> |
| In reply to | #425088 |
In article <MPG.3091d91fe0aa423c989bd3@news.eternal-september.org>, J. Clarke <j.clarke.873638@gmail.com> wrote: >In article <nwKnoK.r4D@kithrup.com>, djheydt@kithrup.com says... >> >> In article <MPG.309112433b139234989bd1@news.eternal-september.org>, >> J. Clarke <j.clarke.873638@gmail.com> wrote: >> >In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... >> >> >> >> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, >> >> Dimensional Traveler <dtravel@sonic.net> wrote: >> >> >On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: >> >> >> In article <n041tp$v9u$1@dont-email.me>, >> >> >> David Johnston <David@block.net> wrote: >> >> >>> On 10/19/2015 6:13 PM, Quadibloc wrote: >> >> >>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J >Heydt wrote: >> >> >>>>> In article <n01tb2$uei$1@dont-email.me>, >> >> >>>>> William Vetter <mdhangton@gmail.com> wrote: >> >> >>>> >> >> >>>>>> Most people don't realize that irrigation salinates soil over the >> >> >>>>>> course of decades as trace salts in the irrigation water are >> >> >>>>>> concentrated, after which more irrigation water is required to flush >> >> >>>>>> out the salts before planting. >> >> >>>> >> >> >>>>>> In the ancient world, this was never a problem in the Nile valley, >> >> >>>>>> because the river would flood its banks every year to do this >> >> >>>>>> automatically, up until the Aswan Dam was built. But it was >a big deal >> >> >>>>>> with the Tigris & Euphrates, which is why the Fertile >Crescent isn't as >> >> >>>>>> fertile as it originally was. >> >> >>>> >> >> >>>>> I knew the Crescent had deteriorated over the centuries because >> >> >>>>> of salts in the soil, the result of irrigation. I didn't realize >> >> >>>>> perchlorates were involved. >> >> >>>> >> >> >>>> I don't believe he was trying to say they were - just that the same >> >> >>> accumulation of ordinary salt that caused problems on Earth >could happen >> >> >>> with perchlorates on Mars if we thought that just washing them out with >> >> >>> water would solve the problem. >> >> >>>> >> >> >>>> John Savard >> >> >>>> >> >> >>> >> >> >>> Just washing out salt with water DOES work. It just takes a whole >> >> >>> heaping lot of water. >> >> >> >> >> >> That drains away somewhere. If you're irrigating the soil with >> >> >> canals full of slightly salty water, then it builds up right >> >> >> where you're trying to grow things. >> >> >> >> >> >It drains away to where the perchlorate eating bacteria is I believe is >> >> >the unstated part of the argument. >> >> >> >> Yup. Find your perchlorate-eating bacteria,* put them down in the >> >> bottomlands, flood the uplands with water, and wait. >> >> >> >> _____ >> >> *Mrs. Beeton never did actually say "First catch your rabbit." >> >> Her recipe began something like "Select your rabbit, and be sure >> >> it is young and tender." >> > >> >The perchlorate eating bacteria seem to be around wherever there is >> >perchlorate and water. They aren't eating the perchlorate in the >> >Atacama Desert for example, where concentrations can be as high as .25 >> >percent. >> > >> >Note that travel through the Atacama is not the instant perchlorate >> >death that the "Perchlorate will prevent Mars exploration" people seem >> >to think it should be. >> >> Well, no, as long as the human explorers stay inside their >> spacesits and clean off thoroughly before entering the habitat. >> But we're talking about trying to terraform the place. > >Friend of mine spent a good bit of time in the Atacama. No spacesuit in >sight. And he's far from dead. Hm. I assume he's an astronomer? -- Dorothy J. Heydt Vallejo, California djheydt at gmail dot com
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| From | "J. Clarke" <j.clarke.873638@gmail.com> |
|---|---|
| Date | 2015-10-21 23:22 -0400 |
| Message-ID | <MPG.3092207a2e5b8457989bd5@news.eternal-september.org> |
| In reply to | #425092 |
In article <nwLG0v.6sL@kithrup.com>, djheydt@kithrup.com says... > > In article <MPG.3091d91fe0aa423c989bd3@news.eternal-september.org>, > J. Clarke <j.clarke.873638@gmail.com> wrote: > >In article <nwKnoK.r4D@kithrup.com>, djheydt@kithrup.com says... > >> > >> In article <MPG.309112433b139234989bd1@news.eternal-september.org>, > >> J. Clarke <j.clarke.873638@gmail.com> wrote: > >> >In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... > >> >> > >> >> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, > >> >> Dimensional Traveler <dtravel@sonic.net> wrote: > >> >> >On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: > >> >> >> In article <n041tp$v9u$1@dont-email.me>, > >> >> >> David Johnston <David@block.net> wrote: > >> >> >>> On 10/19/2015 6:13 PM, Quadibloc wrote: > >> >> >>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J > >Heydt wrote: > >> >> >>>>> In article <n01tb2$uei$1@dont-email.me>, > >> >> >>>>> William Vetter <mdhangton@gmail.com> wrote: > >> >> >>>> > >> >> >>>>>> Most people don't realize that irrigation salinates soil over the > >> >> >>>>>> course of decades as trace salts in the irrigation water are > >> >> >>>>>> concentrated, after which more irrigation water is required to flush > >> >> >>>>>> out the salts before planting. > >> >> >>>> > >> >> >>>>>> In the ancient world, this was never a problem in the Nile valley, > >> >> >>>>>> because the river would flood its banks every year to do this > >> >> >>>>>> automatically, up until the Aswan Dam was built. But it was > >a big deal > >> >> >>>>>> with the Tigris & Euphrates, which is why the Fertile > >Crescent isn't as > >> >> >>>>>> fertile as it originally was. > >> >> >>>> > >> >> >>>>> I knew the Crescent had deteriorated over the centuries because > >> >> >>>>> of salts in the soil, the result of irrigation. I didn't realize > >> >> >>>>> perchlorates were involved. > >> >> >>>> > >> >> >>>> I don't believe he was trying to say they were - just that the same > >> >> >>> accumulation of ordinary salt that caused problems on Earth > >could happen > >> >> >>> with perchlorates on Mars if we thought that just washing them out with > >> >> >>> water would solve the problem. > >> >> >>>> > >> >> >>>> John Savard > >> >> >>>> > >> >> >>> > >> >> >>> Just washing out salt with water DOES work. It just takes a whole > >> >> >>> heaping lot of water. > >> >> >> > >> >> >> That drains away somewhere. If you're irrigating the soil with > >> >> >> canals full of slightly salty water, then it builds up right > >> >> >> where you're trying to grow things. > >> >> >> > >> >> >It drains away to where the perchlorate eating bacteria is I believe is > >> >> >the unstated part of the argument. > >> >> > >> >> Yup. Find your perchlorate-eating bacteria,* put them down in the > >> >> bottomlands, flood the uplands with water, and wait. > >> >> > >> >> _____ > >> >> *Mrs. Beeton never did actually say "First catch your rabbit." > >> >> Her recipe began something like "Select your rabbit, and be sure > >> >> it is young and tender." > >> > > >> >The perchlorate eating bacteria seem to be around wherever there is > >> >perchlorate and water. They aren't eating the perchlorate in the > >> >Atacama Desert for example, where concentrations can be as high as .25 > >> >percent. > >> > > >> >Note that travel through the Atacama is not the instant perchlorate > >> >death that the "Perchlorate will prevent Mars exploration" people seem > >> >to think it should be. > >> > >> Well, no, as long as the human explorers stay inside their > >> spacesits and clean off thoroughly before entering the habitat. > >> But we're talking about trying to terraform the place. > > > >Friend of mine spent a good bit of time in the Atacama. No spacesuit in > >sight. And he's far from dead. > > Hm. I assume he's an astronomer? Nope, just an adventurer. He's also been up Everest and done other suchlike.
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| From | Dimensional Traveler <dtravel@sonic.net> |
|---|---|
| Date | 2015-10-21 20:01 -0700 |
| Message-ID | <56285170$0$1675$742ec2ed@news.sonic.net> |
| In reply to | #425073 |
On 10/21/2015 6:19 AM, Dorothy J Heydt wrote: > In article <MPG.309112433b139234989bd1@news.eternal-september.org>, > J. Clarke <j.clarke.873638@gmail.com> wrote: >> In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... >>> >>> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, >>> Dimensional Traveler <dtravel@sonic.net> wrote: >>>> On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: >>>>> In article <n041tp$v9u$1@dont-email.me>, >>>>> David Johnston <David@block.net> wrote: >>>>>> On 10/19/2015 6:13 PM, Quadibloc wrote: >>>>>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: >>>>>>>> In article <n01tb2$uei$1@dont-email.me>, >>>>>>>> William Vetter <mdhangton@gmail.com> wrote: >>>>>>> >>>>>>>>> Most people don't realize that irrigation salinates soil over the >>>>>>>>> course of decades as trace salts in the irrigation water are >>>>>>>>> concentrated, after which more irrigation water is required to flush >>>>>>>>> out the salts before planting. >>>>>>> >>>>>>>>> In the ancient world, this was never a problem in the Nile valley, >>>>>>>>> because the river would flood its banks every year to do this >>>>>>>>> automatically, up until the Aswan Dam was built. But it was a big deal >>>>>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent isn't as >>>>>>>>> fertile as it originally was. >>>>>>> >>>>>>>> I knew the Crescent had deteriorated over the centuries because >>>>>>>> of salts in the soil, the result of irrigation. I didn't realize >>>>>>>> perchlorates were involved. >>>>>>> >>>>>>> I don't believe he was trying to say they were - just that the same >>>>>> accumulation of ordinary salt that caused problems on Earth could happen >>>>>> with perchlorates on Mars if we thought that just washing them out with >>>>>> water would solve the problem. >>>>>>> >>>>>>> John Savard >>>>>>> >>>>>> >>>>>> Just washing out salt with water DOES work. It just takes a whole >>>>>> heaping lot of water. >>>>> >>>>> That drains away somewhere. If you're irrigating the soil with >>>>> canals full of slightly salty water, then it builds up right >>>>> where you're trying to grow things. >>>>> >>>> It drains away to where the perchlorate eating bacteria is I believe is >>>> the unstated part of the argument. >>> >>> Yup. Find your perchlorate-eating bacteria,* put them down in the >>> bottomlands, flood the uplands with water, and wait. >>> >>> _____ >>> *Mrs. Beeton never did actually say "First catch your rabbit." >>> Her recipe began something like "Select your rabbit, and be sure >>> it is young and tender." >> >> The perchlorate eating bacteria seem to be around wherever there is >> perchlorate and water. They aren't eating the perchlorate in the >> Atacama Desert for example, where concentrations can be as high as .25 >> percent. >> >> Note that travel through the Atacama is not the instant perchlorate >> death that the "Perchlorate will prevent Mars exploration" people seem >> to think it should be. > > Well, no, as long as the human explorers stay inside their > spacesits and clean off thoroughly before entering the habitat. > But we're talking about trying to terraform the place. > Terraforming Mars: Step 1: throw lots of icy comets at planet. -- Even Confucius complained about the younger generation's music.
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| From | djheydt@kithrup.com (Dorothy J Heydt) |
|---|---|
| Date | 2015-10-22 03:38 +0000 |
| Message-ID | <nwLrFn.sHu@kithrup.com> |
| In reply to | #425100 |
In article <56285170$0$1675$742ec2ed@news.sonic.net>, Dimensional Traveler <dtravel@sonic.net> wrote: >On 10/21/2015 6:19 AM, Dorothy J Heydt wrote: >> In article <MPG.309112433b139234989bd1@news.eternal-september.org>, >> J. Clarke <j.clarke.873638@gmail.com> wrote: >>> In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... >>>> >>>> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, >>>> Dimensional Traveler <dtravel@sonic.net> wrote: >>>>> On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: >>>>>> In article <n041tp$v9u$1@dont-email.me>, >>>>>> David Johnston <David@block.net> wrote: >>>>>>> On 10/19/2015 6:13 PM, Quadibloc wrote: >>>>>>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: >>>>>>>>> In article <n01tb2$uei$1@dont-email.me>, >>>>>>>>> William Vetter <mdhangton@gmail.com> wrote: >>>>>>>> >>>>>>>>>> Most people don't realize that irrigation salinates soil over the >>>>>>>>>> course of decades as trace salts in the irrigation water are >>>>>>>>>> concentrated, after which more irrigation water is required to flush >>>>>>>>>> out the salts before planting. >>>>>>>> >>>>>>>>>> In the ancient world, this was never a problem in the Nile valley, >>>>>>>>>> because the river would flood its banks every year to do this >>>>>>>>>> automatically, up until the Aswan Dam was built. But it was a >big deal >>>>>>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent >isn't as >>>>>>>>>> fertile as it originally was. >>>>>>>> >>>>>>>>> I knew the Crescent had deteriorated over the centuries because >>>>>>>>> of salts in the soil, the result of irrigation. I didn't realize >>>>>>>>> perchlorates were involved. >>>>>>>> >>>>>>>> I don't believe he was trying to say they were - just that the same >>>>>>> accumulation of ordinary salt that caused problems on Earth could happen >>>>>>> with perchlorates on Mars if we thought that just washing them out with >>>>>>> water would solve the problem. >>>>>>>> >>>>>>>> John Savard >>>>>>>> >>>>>>> >>>>>>> Just washing out salt with water DOES work. It just takes a whole >>>>>>> heaping lot of water. >>>>>> >>>>>> That drains away somewhere. If you're irrigating the soil with >>>>>> canals full of slightly salty water, then it builds up right >>>>>> where you're trying to grow things. >>>>>> >>>>> It drains away to where the perchlorate eating bacteria is I believe is >>>>> the unstated part of the argument. >>>> >>>> Yup. Find your perchlorate-eating bacteria,* put them down in the >>>> bottomlands, flood the uplands with water, and wait. >>>> >>>> _____ >>>> *Mrs. Beeton never did actually say "First catch your rabbit." >>>> Her recipe began something like "Select your rabbit, and be sure >>>> it is young and tender." >>> >>> The perchlorate eating bacteria seem to be around wherever there is >>> perchlorate and water. They aren't eating the perchlorate in the >>> Atacama Desert for example, where concentrations can be as high as .25 >>> percent. >>> >>> Note that travel through the Atacama is not the instant perchlorate >>> death that the "Perchlorate will prevent Mars exploration" people seem >>> to think it should be. >> >> Well, no, as long as the human explorers stay inside their >> spacesits and clean off thoroughly before entering the habitat. >> But we're talking about trying to terraform the place. >> >Terraforming Mars: > >Step 1: throw lots of icy comets at planet. That's certainly one of the steps. I'm not sure if it's 1 or not. -- Dorothy J. Heydt Vallejo, California djheydt at gmail dot com
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| From | Dimensional Traveler <dtravel@sonic.net> |
|---|---|
| Date | 2015-10-22 17:11 -0700 |
| Message-ID | <56297b4f$0$1640$742ec2ed@news.sonic.net> |
| In reply to | #425104 |
On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: > In article <56285170$0$1675$742ec2ed@news.sonic.net>, > Dimensional Traveler <dtravel@sonic.net> wrote: >> On 10/21/2015 6:19 AM, Dorothy J Heydt wrote: >>> In article <MPG.309112433b139234989bd1@news.eternal-september.org>, >>> J. Clarke <j.clarke.873638@gmail.com> wrote: >>>> In article <nwJy24.12K1@kithrup.com>, djheydt@kithrup.com says... >>>>> >>>>> In article <562708a0$0$1703$742ec2ed@news.sonic.net>, >>>>> Dimensional Traveler <dtravel@sonic.net> wrote: >>>>>> On 10/19/2015 7:17 PM, Dorothy J Heydt wrote: >>>>>>> In article <n041tp$v9u$1@dont-email.me>, >>>>>>> David Johnston <David@block.net> wrote: >>>>>>>> On 10/19/2015 6:13 PM, Quadibloc wrote: >>>>>>>>> On Monday, October 19, 2015 at 7:30:07 AM UTC-6, Dorothy J Heydt wrote: >>>>>>>>>> In article <n01tb2$uei$1@dont-email.me>, >>>>>>>>>> William Vetter <mdhangton@gmail.com> wrote: >>>>>>>>> >>>>>>>>>>> Most people don't realize that irrigation salinates soil over the >>>>>>>>>>> course of decades as trace salts in the irrigation water are >>>>>>>>>>> concentrated, after which more irrigation water is required to flush >>>>>>>>>>> out the salts before planting. >>>>>>>>> >>>>>>>>>>> In the ancient world, this was never a problem in the Nile valley, >>>>>>>>>>> because the river would flood its banks every year to do this >>>>>>>>>>> automatically, up until the Aswan Dam was built. But it was a >> big deal >>>>>>>>>>> with the Tigris & Euphrates, which is why the Fertile Crescent >> isn't as >>>>>>>>>>> fertile as it originally was. >>>>>>>>> >>>>>>>>>> I knew the Crescent had deteriorated over the centuries because >>>>>>>>>> of salts in the soil, the result of irrigation. I didn't realize >>>>>>>>>> perchlorates were involved. >>>>>>>>> >>>>>>>>> I don't believe he was trying to say they were - just that the same >>>>>>>> accumulation of ordinary salt that caused problems on Earth could happen >>>>>>>> with perchlorates on Mars if we thought that just washing them out with >>>>>>>> water would solve the problem. >>>>>>>>> >>>>>>>>> John Savard >>>>>>>>> >>>>>>>> >>>>>>>> Just washing out salt with water DOES work. It just takes a whole >>>>>>>> heaping lot of water. >>>>>>> >>>>>>> That drains away somewhere. If you're irrigating the soil with >>>>>>> canals full of slightly salty water, then it builds up right >>>>>>> where you're trying to grow things. >>>>>>> >>>>>> It drains away to where the perchlorate eating bacteria is I believe is >>>>>> the unstated part of the argument. >>>>> >>>>> Yup. Find your perchlorate-eating bacteria,* put them down in the >>>>> bottomlands, flood the uplands with water, and wait. >>>>> >>>>> _____ >>>>> *Mrs. Beeton never did actually say "First catch your rabbit." >>>>> Her recipe began something like "Select your rabbit, and be sure >>>>> it is young and tender." >>>> >>>> The perchlorate eating bacteria seem to be around wherever there is >>>> perchlorate and water. They aren't eating the perchlorate in the >>>> Atacama Desert for example, where concentrations can be as high as .25 >>>> percent. >>>> >>>> Note that travel through the Atacama is not the instant perchlorate >>>> death that the "Perchlorate will prevent Mars exploration" people seem >>>> to think it should be. >>> >>> Well, no, as long as the human explorers stay inside their >>> spacesits and clean off thoroughly before entering the habitat. >>> But we're talking about trying to terraform the place. >>> >> Terraforming Mars: >> >> Step 1: throw lots of icy comets at planet. > > That's certainly one of the steps. I'm not sure if it's 1 or > not. > Is there something else that has to be done on/to the planet before you can start throwing giant snowballs at it? Or that would be significantly easier to do before rather than after? -- Even Confucius complained about the younger generation's music.
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| From | Quadibloc <jsavard@ecn.ab.ca> |
|---|---|
| Date | 2015-10-22 17:38 -0700 |
| Message-ID | <a74598c5-4126-4cde-afca-96724b78ac48@googlegroups.com> |
| In reply to | #425143 |
On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional Traveler wrote: > On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: > > In article <56285170$0$1675$742ec2ed@news.sonic.net>, > > Dimensional Traveler <dtravel@sonic.net> wrote: > >> Step 1: throw lots of icy comets at planet. > > That's certainly one of the steps. I'm not sure if it's 1 or > > not. > Is there something else that has to be done on/to the planet before you > can start throwing giant snowballs at it? Or that would be > significantly easier to do before rather than after? I'm certainly inclined towards doing it rather early in the plan. It's much easier to throw comets at a planet, if one's intentions are benign, when there isn't anything important for them to accidentally *hit* yet. If the plan included increasing Mars' gravity, say by dropping Mercury on it, then, as that would (ultimately) reduce the rate at which volatiles escape into space (and it would also, temporarily, make Mars rather *hot*, given the release of energy involved, resulting in the loss of a lot of volatiles) one would do _that_ before sending in the comets. But that kind of plan involves far-future technology, and thus is not the usual sort of terraforming plan. John Savard
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| From | Greg Goss <gossg@gossg.org> |
|---|---|
| Date | 2015-10-22 22:28 -0600 |
| Message-ID | <d8trbkF3nlbU1@mid.individual.net> |
| In reply to | #425145 |
Quadibloc <jsavard@ecn.ab.ca> wrote: >If the plan included increasing Mars' gravity, say by dropping Mercury on it, >then, as that would (ultimately) reduce the rate at which volatiles escape into >space (and it would also, temporarily, make Mars rather *hot*, given the >release of energy involved, resulting in the loss of a lot of volatiles) one >would do _that_ before sending in the comets. But that kind of plan involves >far-future technology, and thus is not the usual sort of terraforming plan. Niven moved planets around by floating a nuclear ramjet rocket in the atmosphere of a gas giant, then using that to move the gas giant around to push the rest of the planets with gravity. It wasn't until my third read of the novel that I realized Niven was moving stuff around the solar system by shoving a hot rocket up Uranus. -- We are geeks. Resistance is voltage over current.
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| From | Walter Bushell <proto@panix.com> |
|---|---|
| Date | 2015-10-26 23:16 -0400 |
| Message-ID | <proto-C0CB4B.23155426102015@news.panix.com> |
| In reply to | #425159 |
In article <d8trbkF3nlbU1@mid.individual.net>, Greg Goss <gossg@gossg.org> wrote: > It wasn't until my third read of the novel that I realized Niven was > moving stuff around the solar system by shoving a hot rocket up > Uranus. s/hot rocket/white hot rocket/ At that temperature you'd hardly feel anything. -- Never attribute to stupidity that which can be explained by greed. Me.
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| From | Robert Bannister <robban@clubtelco.com> |
|---|---|
| Date | 2015-10-23 14:48 +0800 |
| Message-ID | <d8u3hmF5jpsU1@mid.individual.net> |
| In reply to | #425145 |
On 23/10/2015 8:38 AM, Quadibloc wrote: > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional Traveler wrote: >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, >>> Dimensional Traveler <dtravel@sonic.net> wrote: > >>>> Step 1: throw lots of icy comets at planet. > >>> That's certainly one of the steps. I'm not sure if it's 1 or >>> not. > >> Is there something else that has to be done on/to the planet before you >> can start throwing giant snowballs at it? Or that would be >> significantly easier to do before rather than after? > > I'm certainly inclined towards doing it rather early in the plan. It's much > easier to throw comets at a planet, if one's intentions are benign, when there > isn't anything important for them to accidentally *hit* yet. > > If the plan included increasing Mars' gravity, say by dropping Mercury on it, > then, as that would (ultimately) reduce the rate at which volatiles escape into > space (and it would also, temporarily, make Mars rather *hot*, given the > release of energy involved, resulting in the loss of a lot of volatiles) one > would do _that_ before sending in the comets. But that kind of plan involves > far-future technology, and thus is not the usual sort of terraforming plan. Isn't one of Mars's moons close to losing its orbit or am I totally off-beam? Maybe it would be a good idea to help it on its way first. -- Robert Bannister Perth, Western Australia
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| From | petertrei@gmail.com |
|---|---|
| Date | 2015-10-23 08:07 -0700 |
| Message-ID | <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com> |
| In reply to | #425173 |
On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister wrote: > On 23/10/2015 8:38 AM, Quadibloc wrote: > > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional Traveler wrote: > >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: > >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, > >>> Dimensional Traveler <dtravel@sonic.net> wrote: > > > >>>> Step 1: throw lots of icy comets at planet. > > > >>> That's certainly one of the steps. I'm not sure if it's 1 or > >>> not. > > > >> Is there something else that has to be done on/to the planet before you > >> can start throwing giant snowballs at it? Or that would be > >> significantly easier to do before rather than after? > > > > I'm certainly inclined towards doing it rather early in the plan. It's much > > easier to throw comets at a planet, if one's intentions are benign, when there > > isn't anything important for them to accidentally *hit* yet. > > > > If the plan included increasing Mars' gravity, say by dropping Mercury on it, > > then, as that would (ultimately) reduce the rate at which volatiles escape into > > space (and it would also, temporarily, make Mars rather *hot*, given the > > release of energy involved, resulting in the loss of a lot of volatiles) one > > would do _that_ before sending in the comets. But that kind of plan involves > > far-future technology, and thus is not the usual sort of terraforming plan. > > Isn't one of Mars's moons close to losing its orbit or am I totally > off-beam? Maybe it would be a good idea to help it on its way first. It isn't even near big enough. Running the numbers.... (all weights at Earth gravity) Earth's atmosphere weighs 5e18 kg Mars' surface area is 27.5% of Earth's. Thus, to put the same atmosphereic mass/surface area on Mars, we'd need 1.4e18 kg of gases That would provide the same amount of shielding as we get from Earth's atmosphere. But, since we're terraforming, we also need to be able to breath. Since Mars' gravity is 37.6% of Earth's, the pressure at the surface would only be 0.376 atmosphere, and unbreathable (equiv to over 24,000 feet, or 7.5 km). To get 1 atm pressure on Mars' surface, we'd need 3.7e18 kg of gases (or arrange for a 50% oxygen atmosphere). Water isn't air, and an ice asteroid wouldn't create that much atmosphere, but I'll use water as a proxy to give an approximate idea of the size of object needed. 1.4e18 kg of ice = 140 km diameter 3.76e18 kg of ice = 200 km diameter (about the size of Mimas) This is well into 'earth/mars-shattering Kaboom!' territory. I'd highly advise dropping much smaller chunks. pt
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| From | djheydt@kithrup.com (Dorothy J Heydt) |
|---|---|
| Date | 2015-10-23 15:33 +0000 |
| Message-ID | <nwoJ8F.DB5@kithrup.com> |
| In reply to | #425186 |
In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, <petertrei@gmail.com> wrote: >On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister wrote: >> On 23/10/2015 8:38 AM, Quadibloc wrote: >> > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional >Traveler wrote: >> >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: >> >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, >> >>> Dimensional Traveler <dtravel@sonic.net> wrote: >> > >> >>>> Step 1: throw lots of icy comets at planet. >> > >> >>> That's certainly one of the steps. I'm not sure if it's 1 or >> >>> not. >> > >> >> Is there something else that has to be done on/to the planet before you >> >> can start throwing giant snowballs at it? Or that would be >> >> significantly easier to do before rather than after? >> > >> > I'm certainly inclined towards doing it rather early in the plan. It's much >> > easier to throw comets at a planet, if one's intentions are benign, >when there >> > isn't anything important for them to accidentally *hit* yet. >> > >> > If the plan included increasing Mars' gravity, say by dropping >Mercury on it, >> > then, as that would (ultimately) reduce the rate at which volatiles >escape into >> > space (and it would also, temporarily, make Mars rather *hot*, given the >> > release of energy involved, resulting in the loss of a lot of volatiles) one >> > would do _that_ before sending in the comets. But that kind of plan involves >> > far-future technology, and thus is not the usual sort of terraforming plan. >> >> Isn't one of Mars's moons close to losing its orbit or am I totally >> off-beam? Maybe it would be a good idea to help it on its way first. > >It isn't even near big enough. > >Running the numbers.... > >(all weights at Earth gravity) > >Earth's atmosphere weighs 5e18 kg >Mars' surface area is 27.5% of Earth's. >Thus, to put the same atmosphereic mass/surface >area on Mars, we'd need 1.4e18 kg of gases > >That would provide the same amount of shielding as >we get from Earth's atmosphere. > >But, since we're terraforming, we also need to be >able to breath. Since Mars' gravity is 37.6% of >Earth's, the pressure at the surface would only be >0.376 atmosphere, and unbreathable (equiv to over >24,000 feet, or 7.5 km). To get 1 atm pressure on >Mars' surface, we'd need 3.7e18 kg of gases (or >arrange for a 50% oxygen atmosphere). > >Water isn't air, and an ice asteroid wouldn't create >that much atmosphere, but I'll use water as a proxy to >give an approximate idea of the size of object needed. > >1.4e18 kg of ice = 140 km diameter >3.76e18 kg of ice = 200 km diameter (about the size of Mimas) > >This is well into 'earth/mars-shattering Kaboom!' >territory. I'd highly advise dropping much smaller >chunks. If you can really fine-tune your orbits, maybe several Mars-grazing passes to let the Oort-object sublime off a lot of its mass before its final impact? Note that I am not a physicist, and don't have the foggiest whether this would work or not. One might have to mount thrusters on the object and nudge it after each pass. -- Dorothy J. Heydt Vallejo, California djheydt at gmail dot com
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| From | petertrei@gmail.com |
|---|---|
| Date | 2015-10-23 10:10 -0700 |
| Message-ID | <8ace6372-1704-4055-b89f-15243a5b9d99@googlegroups.com> |
| In reply to | #425190 |
On Friday, October 23, 2015 at 11:45:13 AM UTC-4, Dorothy J Heydt wrote: > In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, > <petertrei@gmail.com> wrote: > >On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister wrote: > >> On 23/10/2015 8:38 AM, Quadibloc wrote: > >> > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional > >Traveler wrote: > >> >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: > >> >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, > >> >>> Dimensional Traveler <dtravel@sonic.net> wrote: > >> > > >> >>>> Step 1: throw lots of icy comets at planet. > >> > > >> >>> That's certainly one of the steps. I'm not sure if it's 1 or > >> >>> not. > >> > > >> >> Is there something else that has to be done on/to the planet before you > >> >> can start throwing giant snowballs at it? Or that would be > >> >> significantly easier to do before rather than after? > >> > > >> > I'm certainly inclined towards doing it rather early in the plan. It's much > >> > easier to throw comets at a planet, if one's intentions are benign, > >when there > >> > isn't anything important for them to accidentally *hit* yet. > >> > > >> > If the plan included increasing Mars' gravity, say by dropping > >Mercury on it, > >> > then, as that would (ultimately) reduce the rate at which volatiles > >escape into > >> > space (and it would also, temporarily, make Mars rather *hot*, given the > >> > release of energy involved, resulting in the loss of a lot of volatiles) one > >> > would do _that_ before sending in the comets. But that kind of plan involves > >> > far-future technology, and thus is not the usual sort of terraforming plan. > >> > >> Isn't one of Mars's moons close to losing its orbit or am I totally > >> off-beam? Maybe it would be a good idea to help it on its way first. > > > >It isn't even near big enough. > > > >Running the numbers.... > > > >(all weights at Earth gravity) > > > >Earth's atmosphere weighs 5e18 kg > >Mars' surface area is 27.5% of Earth's. > >Thus, to put the same atmosphereic mass/surface > >area on Mars, we'd need 1.4e18 kg of gases > > > >That would provide the same amount of shielding as > >we get from Earth's atmosphere. > > > >But, since we're terraforming, we also need to be > >able to breath. Since Mars' gravity is 37.6% of > >Earth's, the pressure at the surface would only be > >0.376 atmosphere, and unbreathable (equiv to over > >24,000 feet, or 7.5 km). To get 1 atm pressure on > >Mars' surface, we'd need 3.7e18 kg of gases (or > >arrange for a 50% oxygen atmosphere). > > > >Water isn't air, and an ice asteroid wouldn't create > >that much atmosphere, but I'll use water as a proxy to > >give an approximate idea of the size of object needed. > > > >1.4e18 kg of ice = 140 km diameter > >3.76e18 kg of ice = 200 km diameter (about the size of Mimas) > > > >This is well into 'earth/mars-shattering Kaboom!' > >territory. I'd highly advise dropping much smaller > >chunks. > > If you can really fine-tune your orbits, maybe several > Mars-grazing passes to let the Oort-object sublime off a lot of > its mass before its final impact? Note that I am not a > physicist, and don't have the foggiest whether this would work or > not. One might have to mount thrusters on the object and nudge > it after each pass. "Several passes"? Think about the size - over 100 miles across, and the thinness of the Martian atmosphere. I don't think this would work. pt
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| From | Dimensional Traveler <dtravel@sonic.net> |
|---|---|
| Date | 2015-10-23 19:07 -0700 |
| Message-ID | <562ae7d0$0$1641$742ec2ed@news.sonic.net> |
| In reply to | #425193 |
On 10/23/2015 10:10 AM, petertrei@gmail.com wrote: > On Friday, October 23, 2015 at 11:45:13 AM UTC-4, Dorothy J Heydt wrote: >> In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, >> <petertrei@gmail.com> wrote: >>> On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister wrote: >>>> On 23/10/2015 8:38 AM, Quadibloc wrote: >>>>> On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional >>> Traveler wrote: >>>>>> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: >>>>>>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, >>>>>>> Dimensional Traveler <dtravel@sonic.net> wrote: >>>>> >>>>>>>> Step 1: throw lots of icy comets at planet. >>>>> >>>>>>> That's certainly one of the steps. I'm not sure if it's 1 or >>>>>>> not. >>>>> >>>>>> Is there something else that has to be done on/to the planet before you >>>>>> can start throwing giant snowballs at it? Or that would be >>>>>> significantly easier to do before rather than after? >>>>> >>>>> I'm certainly inclined towards doing it rather early in the plan. It's much >>>>> easier to throw comets at a planet, if one's intentions are benign, >>> when there >>>>> isn't anything important for them to accidentally *hit* yet. >>>>> >>>>> If the plan included increasing Mars' gravity, say by dropping >>> Mercury on it, >>>>> then, as that would (ultimately) reduce the rate at which volatiles >>> escape into >>>>> space (and it would also, temporarily, make Mars rather *hot*, given the >>>>> release of energy involved, resulting in the loss of a lot of volatiles) one >>>>> would do _that_ before sending in the comets. But that kind of plan involves >>>>> far-future technology, and thus is not the usual sort of terraforming plan. >>>> >>>> Isn't one of Mars's moons close to losing its orbit or am I totally >>>> off-beam? Maybe it would be a good idea to help it on its way first. >>> >>> It isn't even near big enough. >>> >>> Running the numbers.... >>> >>> (all weights at Earth gravity) >>> >>> Earth's atmosphere weighs 5e18 kg >>> Mars' surface area is 27.5% of Earth's. >>> Thus, to put the same atmosphereic mass/surface >>> area on Mars, we'd need 1.4e18 kg of gases >>> >>> That would provide the same amount of shielding as >>> we get from Earth's atmosphere. >>> >>> But, since we're terraforming, we also need to be >>> able to breath. Since Mars' gravity is 37.6% of >>> Earth's, the pressure at the surface would only be >>> 0.376 atmosphere, and unbreathable (equiv to over >>> 24,000 feet, or 7.5 km). To get 1 atm pressure on >>> Mars' surface, we'd need 3.7e18 kg of gases (or >>> arrange for a 50% oxygen atmosphere). >>> >>> Water isn't air, and an ice asteroid wouldn't create >>> that much atmosphere, but I'll use water as a proxy to >>> give an approximate idea of the size of object needed. >>> >>> 1.4e18 kg of ice = 140 km diameter >>> 3.76e18 kg of ice = 200 km diameter (about the size of Mimas) >>> >>> This is well into 'earth/mars-shattering Kaboom!' >>> territory. I'd highly advise dropping much smaller >>> chunks. >> >> If you can really fine-tune your orbits, maybe several >> Mars-grazing passes to let the Oort-object sublime off a lot of >> its mass before its final impact? Note that I am not a >> physicist, and don't have the foggiest whether this would work or >> not. One might have to mount thrusters on the object and nudge >> it after each pass. > > "Several passes"? Think about the size - over 100 miles across, > and the thinness of the Martian atmosphere. I don't think this > would work. > Not a lot of difference between aerobraking on Mars and lithobraking.... -- Even Confucius complained about the younger generation's music.
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| From | Larry Moore <larry@wightman.ca> |
|---|---|
| Date | 2015-10-24 12:56 +0000 |
| Message-ID | <n0fv57$u0e$1@dont-email.me> |
| In reply to | #425193 |
On 2015-10-23, petertrei@gmail.com <petertrei@gmail.com> wrote: > On Friday, October 23, 2015 at 11:45:13 AM UTC-4, Dorothy J Heydt wrote: >> In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, >> <petertrei@gmail.com> wrote: >> >On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister wrote: >> >> On 23/10/2015 8:38 AM, Quadibloc wrote: >> >> > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional >> >Traveler wrote: >> >> >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: >> >> >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, >> >> >>> Dimensional Traveler <dtravel@sonic.net> wrote: >> >> > >> >> >>>> Step 1: throw lots of icy comets at planet. >> >> > >> >> >>> That's certainly one of the steps. I'm not sure if it's 1 or >> >> >>> not. >> >> > >> >> >> Is there something else that has to be done on/to the planet before you >> >> >> can start throwing giant snowballs at it? Or that would be >> >> >> significantly easier to do before rather than after? >> >> > >> >> > I'm certainly inclined towards doing it rather early in the plan. It's much >> >> > easier to throw comets at a planet, if one's intentions are benign, >> >when there >> >> > isn't anything important for them to accidentally *hit* yet. >> >> > >> >> > If the plan included increasing Mars' gravity, say by dropping >> >Mercury on it, >> >> > then, as that would (ultimately) reduce the rate at which volatiles >> >escape into >> >> > space (and it would also, temporarily, make Mars rather *hot*, given the >> >> > release of energy involved, resulting in the loss of a lot of volatiles) one >> >> > would do _that_ before sending in the comets. But that kind of plan involves >> >> > far-future technology, and thus is not the usual sort of terraforming plan. >> >> >> >> Isn't one of Mars's moons close to losing its orbit or am I totally >> >> off-beam? Maybe it would be a good idea to help it on its way first. >> > >> >It isn't even near big enough. >> > >> >Running the numbers.... >> > >> >(all weights at Earth gravity) >> > >> >Earth's atmosphere weighs 5e18 kg >> >Mars' surface area is 27.5% of Earth's. >> >Thus, to put the same atmosphereic mass/surface >> >area on Mars, we'd need 1.4e18 kg of gases >> > >> >That would provide the same amount of shielding as >> >we get from Earth's atmosphere. >> > >> >But, since we're terraforming, we also need to be >> >able to breath. Since Mars' gravity is 37.6% of >> >Earth's, the pressure at the surface would only be >> >0.376 atmosphere, and unbreathable (equiv to over >> >24,000 feet, or 7.5 km). To get 1 atm pressure on >> >Mars' surface, we'd need 3.7e18 kg of gases (or >> >arrange for a 50% oxygen atmosphere). >> > >> >Water isn't air, and an ice asteroid wouldn't create >> >that much atmosphere, but I'll use water as a proxy to >> >give an approximate idea of the size of object needed. >> > >> >1.4e18 kg of ice = 140 km diameter >> >3.76e18 kg of ice = 200 km diameter (about the size of Mimas) >> > >> >This is well into 'earth/mars-shattering Kaboom!' >> >territory. I'd highly advise dropping much smaller >> >chunks. >> >> If you can really fine-tune your orbits, maybe several >> Mars-grazing passes to let the Oort-object sublime off a lot of >> its mass before its final impact? Note that I am not a >> physicist, and don't have the foggiest whether this would work or >> not. One might have to mount thrusters on the object and nudge >> it after each pass. > > "Several passes"? Think about the size - over 100 miles across, > and the thinness of the Martian atmosphere. I don't think this > would work. > > pt Does Roche's Limit also apply here -- Just do the work you find in front of you and enjoy yourself.
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| From | Cryptoengineer <treifamily@gmail.com> |
|---|---|
| Date | 2015-10-24 10:57 -0500 |
| Message-ID | <XnsA53D79A16166Amelchizedek@216.166.97.131> |
| In reply to | #425242 |
Larry Moore <larry@wightman.ca> wrote in news:n0fv57$u0e$1@dont-email.me: > On 2015-10-23, petertrei@gmail.com <petertrei@gmail.com> wrote: >> On Friday, October 23, 2015 at 11:45:13 AM UTC-4, Dorothy J Heydt >> wrote: >>> In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, >>> <petertrei@gmail.com> wrote: >>> >On Friday, October 23, 2015 at 2:48:25 AM UTC-4, Robert Bannister >>> >wrote: >>> >> On 23/10/2015 8:38 AM, Quadibloc wrote: >>> >> > On Thursday, October 22, 2015 at 6:15:11 PM UTC-6, Dimensional >>> >Traveler wrote: >>> >> >> On 10/21/2015 8:38 PM, Dorothy J Heydt wrote: >>> >> >>> In article <56285170$0$1675$742ec2ed@news.sonic.net>, >>> >> >>> Dimensional Traveler <dtravel@sonic.net> wrote: >>> >> > >>> >> >>>> Step 1: throw lots of icy comets at planet. >>> >> > >>> >> >>> That's certainly one of the steps. I'm not sure if it's 1 or >>> >> >>> not. >>> >> > >>> >> >> Is there something else that has to be done on/to the planet >>> >> >> before you can start throwing giant snowballs at it? Or that >>> >> >> would be significantly easier to do before rather than after? >>> >> > >>> >> > I'm certainly inclined towards doing it rather early in the >>> >> > plan. It's much easier to throw comets at a planet, if one's >>> >> > intentions are benign, >>> >when there >>> >> > isn't anything important for them to accidentally *hit* yet. >>> >> > >>> >> > If the plan included increasing Mars' gravity, say by dropping >>> >Mercury on it, >>> >> > then, as that would (ultimately) reduce the rate at which >>> >> > volatiles >>> >escape into >>> >> > space (and it would also, temporarily, make Mars rather *hot*, >>> >> > given the release of energy involved, resulting in the loss of >>> >> > a lot of volatiles) one would do _that_ before sending in the >>> >> > comets. But that kind of plan involves far-future technology, >>> >> > and thus is not the usual sort of terraforming plan. >>> >> >>> >> Isn't one of Mars's moons close to losing its orbit or am I >>> >> totally off-beam? Maybe it would be a good idea to help it on its >>> >> way first. >>> > >>> >It isn't even near big enough. >>> > >>> >Running the numbers.... >>> > >>> >(all weights at Earth gravity) >>> > >>> >Earth's atmosphere weighs 5e18 kg >>> >Mars' surface area is 27.5% of Earth's. >>> >Thus, to put the same atmosphereic mass/surface >>> >area on Mars, we'd need 1.4e18 kg of gases >>> > >>> >That would provide the same amount of shielding as >>> >we get from Earth's atmosphere. >>> > >>> >But, since we're terraforming, we also need to be >>> >able to breath. Since Mars' gravity is 37.6% of >>> >Earth's, the pressure at the surface would only be >>> >0.376 atmosphere, and unbreathable (equiv to over >>> >24,000 feet, or 7.5 km). To get 1 atm pressure on >>> >Mars' surface, we'd need 3.7e18 kg of gases (or >>> >arrange for a 50% oxygen atmosphere). >>> > >>> >Water isn't air, and an ice asteroid wouldn't create >>> >that much atmosphere, but I'll use water as a proxy to >>> >give an approximate idea of the size of object needed. >>> > >>> >1.4e18 kg of ice = 140 km diameter >>> >3.76e18 kg of ice = 200 km diameter (about the size of Mimas) >>> > >>> >This is well into 'earth/mars-shattering Kaboom!' >>> >territory. I'd highly advise dropping much smaller >>> >chunks. >>> >>> If you can really fine-tune your orbits, maybe several >>> Mars-grazing passes to let the Oort-object sublime off a lot of >>> its mass before its final impact? Note that I am not a >>> physicist, and don't have the foggiest whether this would work or >>> not. One might have to mount thrusters on the object and nudge >>> it after each pass. >> >> "Several passes"? Think about the size - over 100 miles across, >> and the thinness of the Martian atmosphere. I don't think this >> would work. >> >> pt > > Does Roche's Limit also apply here > It might. We're right at the border where bodies round themselves out, instead of being potato shaped. If we could put our body in a really tight orbit, it might get pulled apart into a ring, snd rain down more gradually. I suspect many of the chunks would still be unpleasantly large. Of possible relevance is the 'mould mark' on Iapetus: https://en.wikipedia.org/wiki/Equatorial_ridge_on_Iapetus pt
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| From | Anthony Frost <Vulch@vulch.org> |
|---|---|
| Date | 2015-10-25 10:40 +0100 |
| Message-ID | <3ac2e1855%Vulch@kerrier.vulch.org> |
| In reply to | #425247 |
In message <XnsA53D79A16166Amelchizedek@216.166.97.131>
Cryptoengineer <treifamily@gmail.com> wrote:
> If we could put our body in a really tight orbit, it might get pulled
> apart into a ring, snd rain down more gradually. I suspect many of the
> chunks would still be unpleasantly large.
Stick a mass driver on the back and kick out a stream of ice blocks.
Tune the size and velocity of the stream so the main body stays in orbit
from the thrust and the chunks re-enter harmlessly.
Anthony
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| From | wdstarr@panix.com (William December Starr) |
|---|---|
| Date | 2015-10-25 17:23 -0400 |
| Message-ID | <n0jh99$7rv$1@panix3.panix.com> |
| In reply to | #425186 |
In article <a57b5bc4-7dc6-4b34-936a-88601244d681@googlegroups.com>, petertrei@gmail.com said: > Robert Bannister wrote: > >> Isn't one of Mars's moons close to losing its orbit or am I >> totally off-beam? Maybe it would be a good idea to help it on >> its way first. > > It isn't even near big enough. I think Robert meant: wouldn't it be a good idea to deliberately crash this Moon of Damocles on our terms before we put anything remotely valuable underneath it, rather than letting it hang over the place until it decides to come down on its own? -- wds
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