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Catastrophism
Various ^ | Various

Posted on 04/02/2006 2:13:59 PM PDT by SunkenCiv

Did a planetary wobble kill the dinosaurs?
by Nicola Jones
New Scientist
June 27 2001
Bruce Runnegar from the University of California at Los Angeles' Center for Astrobiology... and his colleagues used computer models to map out the Solar System for the past 250 million years. In particular, they looked at the perihelion of each planet - the point in its orbit where it is closest to the Sun. The perihelion of Earth rotates around the Sun with a period of hundreds of thousands of years. Because of subtle tugs and pulls between the planets, this period changes slightly with time... Their model suggests one of these blips significantly changed Mercury's orbit 65 million years ago. This wobble would have pulled at the asteroid belt, increasing the chances that asteroids in the Hungarias region would be knocked out of place. Now the researchers are running a fresh set of models to see how much the orbits of these asteroids changed. It wouldn't have been enough to send a shower of asteroids into the Earth, but Runnegar says the wobble could have sent a single asteroid onto collision course with our planet... Now he is planning to run his models forward in time, to see when the next potentially catastrophic planetary wobble will be.


TOPICS: Miscellaneous
KEYWORDS: bookmark; catastrophism; dallasabbott; emiliospedicato; godsgravesglyphs; impact; spedicato; tethysocean
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Asteroid 1950 DA
Don Yeomans, Site Manager
NASA Near Earth Object Program
When high-precision radar meaurements were included in a new orbit solution, a potentially very close approach to the Earth on March 16, 2880 was discovered to exist. Analysis performed by Giorgini et al and reported in the April 5, 2002 edition of the journal Science ("Asteroid 1950 DA's Encounter With Earth in 2880: Physical Limits of Collision Probability Prediction") determined the impact probability as being at most 1 in 300 and probably even more remote, based on what is known about the asteroid so far. At its greatest, this could represent a risk 50% greater than that of the average background hazard due to all other asteroids from the present era through 2880, as defined by the Palermo Technical Scale (PTS value = +0.17). 1950 DA is the only known asteroid whose hazard could be above the background level.

141 posted on 08/04/2006 8:14:42 PM PDT by SunkenCiv (updated my FR profile on Thursday, July 27, 2006. https://secure.freerepublic.com/donate/)
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To: 75thOVI; AndrewC; Avoiding_Sulla; BenLurkin; Berosus; CGVet58; chilepepper; ckilmer; demlosers; ...

garbageseeker, I tossed your name on the end because I know you've expressed interest in something like this.

Explosions In Space May Have Initiated Ancient Extinction On Earth
Science Daily | 4/12/05 | NASA/Goddard Space Flight Center
Posted on 04/12/2005 4:12:15 PM EDT by doc30
http://www.freerepublic.com/focus/news/1382310/posts

http://www.freerepublic.com/focus/f-news/1048934/posts?page=44#44
http://www.freerepublic.com/focus/f-news/1048934/posts?page=46#46
http://www.freerepublic.com/focus/f-news/1070173/posts?page=21#21
http://www.freerepublic.com/focus/f-news/1278524/posts?page=30#30
http://www.freerepublic.com/focus/f-news/1354126/posts?page=28#28
http://www.freerepublic.com/focus/f-news/1608702/posts?page=14#14

Starburst caused Ordovician mass extinction: scientists
Posted on : Mon, 11 Apr 2005 00:00:00 GMT | Author : Nigel Wright
News Category : Space
http://www.earthtimes.org/articles/show/2373.html


142 posted on 08/08/2006 9:49:14 AM PDT by SunkenCiv (updated my FR profile on Thursday, July 27, 2006. https://secure.freerepublic.com/donate/)
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To: SunkenCiv
Runnegar says the wobble could have sent a single asteroid onto collision course with our planet...

I'm sure we'll have our comet/asteriod deflector in place by then. :-)

143 posted on 08/08/2006 10:42:21 AM PDT by demlosers
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To: demlosers

We could call it the weeble. :')


144 posted on 08/08/2006 9:53:25 PM PDT by SunkenCiv (updated my FR profile on Thursday, July 27, 2006. https://secure.freerepublic.com/donate/)
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To: 75thOVI; AndrewC; Avoiding_Sulla; BenLurkin; Berosus; CGVet58; chilepepper; ckilmer; demlosers; ...
News to me -- in 1958 a 1700+ foot megatsunami was observed, Lituya Bay:
Google
"the pile of water was tremendous"
145 posted on 08/12/2006 6:44:21 PM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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To: SunkenCiv

Eye witness report:

...The Swansons and the Uhlrichs in Lituya Bay rose in alarm to gaze in unbelieving wonder and terror. Swanson and his wife later insisted that the terminal ice mass of Lituya Glacier rose into view from behind a headland up the bay, with great masses falling from its face, and then fell majestically into the water, creating a wave that went over the whole headland. It then caromed down the bay, scouring the shores of their trees, obliterating the mountaineer's campsite, overrunning Cenotaph Island and its lone cabin, and killing the Wagners and all but killing the Swansons in a surfboard kind of plunge of their two boats across 40-foot high LaChausee Spit to destruction in the sea outside - a wave of such improbability as to strain the credulity of later investigators, and to remain a scientific puzzle...

http://wcatwc.arh.noaa.gov/web_tsus/19580710/narrative1.htm

Sounds like a wild ride.


146 posted on 08/12/2006 9:42:56 PM PDT by Fred Nerks (ENEMY + MEDIA = ENEMEDIA)
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To: 75thOVI; AndrewC; Avoiding_Sulla; BenLurkin; Berosus; CGVet58; chilepepper; ckilmer; demlosers; ...
testing, testing...

· Catastrophism ping list · join · view topics · view or post blog · bookmark ·

147 posted on 08/19/2006 1:19:32 AM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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To: annie laurie; garbageseeker; Knitting A Conundrum; 75thOVI; AndrewC; Avoiding_Sulla; BenLurkin; ...
this particular post is also of interest to the X-Planets list.
Moving the Orbits of Planets
by David Jewitt
September 2004
The mechanism was described in 1984 by Julio Fernandez and Wing Ip. In a one-planet solar system, the outward scattering of comets by the planet would cause the planet to spiral in towards the sun. In the real solar system, the motions of the planets are inter-dependent, causing some to move outwards and others inwards. What connects the planets is the transfer of comets (and angular momentum) from one to the other. Neptune scatters comets out to the interstellar medium and inwards, where some meet Uranus and are scattered again. The process repeats down to the innermost big planet Jupiter. Fernandez and Ip showed that massive Jupiter anchors the flow of angular momentum caused by the ejection of comets. It spirals towards the sun but Saturn, Uranus and Neptune drift outwards. It is the outward migration of Neptune that has had (apparently) observable effects on the Kuiper Belt by trapping the Plutinos...

Meanwhile, the Doppler discovery of extrasolar planets orbiting very close to their parent stars has raised a different problem. Many of the planets are so close to their stars (<0.1 AU), and so hot, that they cannot be supposed to have formed where we now observe them. By inference, they could have formed at larger distances (several AU) and then migrated inwards. What would cause this inward migration? As with the solar system case, the root cause may be an exchange of angular momentum with material surrounding the planets at their formation. In particular, if the extrasolar planets formed in massive disks, then torques between the planets and the disks could drive the former inwards.

148 posted on 08/26/2006 5:26:31 PM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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To: SunkenCiv

THANKS


149 posted on 08/26/2006 5:28:38 PM PDT by Quix (LET GOD ARISE AND HIS ENEMIES BE SCATTERED. LET ISRAEL CALL ON GOD AS THEIRS! & ISLAM FLUSH ITSELF)
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To: Quix

My pleasure.


150 posted on 08/26/2006 5:42:37 PM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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related to message 16.
Is Phoebe A Kuiper Belt Object?
by David Jewitt
Last updated Jun 2006
Phoebe is a 200 km scale irregular satellite of Saturn. With a retrograde orbit (inclination 178 deg), Phoebe cannot have formed in a Saturn-associated accretion disk and, instead, is inferred to have been captured from an independent orbit around the Sun... The two main possibilities are that... Phoebe was captured from heliocentric orbit near Saturn, probably in association with planet formation itself... OR... Phoebe was captured from a more distant reservoir, possibly the Kuiper Belt. We do not possess any way to decide clearly between these possibilities. Recently, Kuiper Belt capture has been widely publicised and two (not wholly convincing) strands of evidence have been supplied.

151 posted on 08/26/2006 5:51:48 PM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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To: SunkenCiv
The People's Cube has already weighed in on the Pluto story.


152 posted on 08/26/2006 7:22:58 PM PDT by Berosus ("There is no beauty like Jerusalem, no wealth like Rome, no depravity like Arabia."--the Talmud)
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To: Berosus

Weighed in being the appropriate metaphor, considering who's on the cover. ;')


153 posted on 08/27/2006 6:19:28 PM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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To: 75thOVI; AndrewC; Avoiding_Sulla; BenLurkin; Berosus; CGVet58; chilepepper; ckilmer; demlosers; ...
Didn't check, but this link is probably good and dead.
Earth's Oxygen Enigma
by Kathy A. Svitil
February 11, 2003
Carrine Blank of Washington University in St. Louis
Scientists have long believed that blue-green algae arose 3.5 billion years ago, pumping out oxygen and causing the oceans to fill with rust. Over the next billion years the algae transformed Earth's atmosphere, allowing oxygen-breathing life to evolve. Carrine Blank of Washington University in St. Louis... compared genetic sequences from 53 different groups of bacteria -- including blue-green algae, also known as cyanobacteria -- to construct a detailed family tree. The results confounded her expectations. "Cyanobacteria arose fairly late, about 2.2 or 2.3 billion years ago. That explains why we see this very sudden increase in oxygen, around 2.2 to 2 billion years ago, which has always been a big mystery," she says. The finding implies that something else caused the ocean rusting.

154 posted on 09/02/2006 12:06:42 AM PDT by SunkenCiv (updated my FR profile on Thursday, August 10, 2006. https://secure.freerepublic.com/donate/)
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Comet's course hints at mystery planet [ from 2001 ]
Govert Schilling | last updated February 5th, 2002 | Govert Schilling
Posted on 08/18/2006 5:36:59 PM EDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1686125/posts


155 posted on 10/20/2006 1:08:22 PM PDT by SunkenCiv (Dhimmicrati delenda est! https://secure.freerepublic.com/donate/)
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To: SunkenCiv

Four theoretical causes of the Permian extincion event.

To what extent could the first event have triggered one or more of the other three effects?


156 posted on 11/02/2006 12:48:07 AM PST by gleeaikin
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To: SunkenCiv

ping, many celestial articles, including impact.


157 posted on 11/02/2006 12:49:51 AM PST by gleeaikin
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To: gleeaikin

Hydrogen sulfide is found at depth in the oceans, either as a product of inorganic processes deep in the Earth, or as a biological byproduct. A large ocean impact (or a series of impacts from a former single object that broke up) would release that. However, with large impacts, that wouldn't be the only problem. :')


158 posted on 11/02/2006 6:18:20 AM PST by SunkenCiv (Dhimmicrati delenda est! https://secure.freerepublic.com/donate/)
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one of those old-fashioned topics, with a catastrophism focus:

The Origin of Sex: Cosmic Solution to Ancient Mystery
Source: Reuters
Published: Tuesday July 10 09:57 AM EDT
Author: Robert Roy Britt, Senior Science Writer, SPACE.com
Posted on 07/11/2001 09:23:06 PDT by Junior
http://www.FreeRepublic.com/forum/a3b4c7d6a4873.htm

[original, dead link]

http://dailynews.yahoo.com/h/space/20010710/sc/the_origin_of_sex_cosmic_solution_to_ancient_mystery_1.html

[also at http://www.space.com/scienceastronomy/solarsystem/origin_sex_010710.html ]


159 posted on 01/14/2007 9:13:34 PM PST by SunkenCiv ("I've learned to live with not knowing." -- Richard Feynman https://secure.freerepublic.com/donate/)
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Some old logo prototypes, finally uploaded for future use:
Catastrophism
Catastrophism

160 posted on 02/03/2007 11:30:53 AM PST by SunkenCiv (I last updated my profile on Wednesday, January 31, 2007. https://secure.freerepublic.com/donate/)
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