Transcript Nemesis - The Evergreen State College

Nemesis: Death From Beyond the Oort Cloud
Brian Flewell; Student, The Evergreen State College, Olympia, WA 98505; 360-866-0619
Extinctions Are Periodic
In the last three decades,
greater and greater proof of
asteroid or comet impacts have
begun to show why there is an
apparent periodicity to the
extinction rate.
The Nemesis theory arose in the 1980s as one of three
possible explanations to, seemingly, periodic mass
extinctions in the earth’s geologic record. According to
Jack Sepkoski and David Raup, there is a 26-million to
31-million year cycle of mass extinctions dating back as
far as 600-million year to the Precambrian era.
This research is backed by M. Davis, P. Hut, and R.A.
Muller who studied the impact history of several of
Earth’s craters, announcing a 28-million year periodicity.
It is with this in mind, I wanted to determine if the
Nemesis theory is the most plausible explanation to a
periodic mass extinction on Earth.
RESEARCH POINTS:
Does/Can Nemesis Exist?
Can the data collected by paleontologists and
physicists who presented a possible explanation to
Sepkoski and Raup’s periodic extinction theory be
proven?
By understanding the Hertzsprung-Russell (H-R)
Diagram, can an apparent magnitude (from Earth) of
Nemesis be determined?
Can a proof for Nemesis be developed to show
Nemesis’ gravitational pull on the Sun?
www.carleton.ca/…/cambrian/cambrianex1.html
Note the peaks on this chart.
They are very nearly evenly
spaced at 29-million years.
Nemesis is one of many theories to be put forward to
answer the question of periodic extinctions on Earth.
I hope to show that a sub-stellar object, a brown
dwarf, beyond Pluto is causing an increase in the
amount of comets and comet fragments from the
Oort Cloud and the Kupier Belt that are sent to the
inner Solar System, resulting in the increased
probability of a comet impacting Earth.
Nemesis’ mass is critical to what Nemesis may be. In order to be
considered a Brown Dwarf, a star that didn’t accrete enough mass
to begin Hydrogen fusion, Nemesis must have a mass at least 10
times that of Jupiter.
Kepler’s Third Law states:
where P is the Period in
years, m1 is the primary mass in kilograms, m2 is the secondary
mass in kilograms, and a is the semi-major axis in Astronomical
Units. To determine that mass of an unknown object we use the
equation:
It is commonly accepted that the impact crater in the Yucatan
Peninsula is from the K-T impact, the death blow to the Dinosaurs
65-million years ago. It has been recently shown that the PermianTriassic extinction 251-million years ago was also caused by an
asteroid impact. It is becoming more likely that most, if not all,
mass extinction events are caused by extraterrestrial sources.
Using the data: P=29.2*106 years, m1 = 2*1030kg (MΘ), and a =
94860 A.U. we determine the mass of Nemesis to be
approximately 8.6*10-4MΘ, or 1.72*1026 kg. This shows that the
mass of Nemesis is somewhere between Uranus and Saturn. Far
too small to be a Brown Dwarf.
Nemesis’ Orbit
Observable Trials of the Nemesis Theory
In order for Nemesis to have the proper
orbit of 29-million years, it must have a
semi-major axis of 1.5 light-years away
from the sun. This orbit it highly elliptical,
bringing Nemesis as close as .5 lightyears, in to the Oort Cloud of comets and
as far as 3 light-years, 3/4 the distance to
the nearest star, Alpha Centauri.
To confirm the period of Nemesis, we use the Keplerian Velocity
Curve a3 = p2. Where a is the semi-major axis of 94860 A.U. (1.5
light-years) and p is the period of Nemesis.
948603 = 8.5*1014 p2= 8.5*1014 √p2=√8.5*1014=29.2*106
p = 29.2 *106 years!
Conclusions
THESIS:
Nemesis’ Mass
Based on my calculations, Nemesis has a semi-major axis of 1.5
light-years or 94,860A.U. Which does give this object the
necessary period of 29.2-million years. After studying the graphs
and proofs of the extinction record, It is the opinion of this
researcher that most, if not all, of the mass extinctions over the
past 250-million years have been caused by comet and/or asteroid
impacts.
However, the theory of a brown dwarf is unlikely, my thesis
incorrect. My mass calculations show the mass to be 1.72*1026 kg,
far smaller than Jupiter and no where large enough to be a brown
dwarf.
This does not, however, rule out the probability of a Jovan sized
planet beyond the orbit of Pluto. There is still the unsolved
question of what is causing the periodic bombardment of the inner
solar system. My research can not answer this.
To determine what effects Nemesis would have on Sol, we will
test the 19MJupiter that I have earlier presented. First, assuming
that all planets in the Solar System have negligible effects on the
Sun, a Saturn size Nemesis would also have a negligible effect
on Sol and therefor be undetectable. To test the 19 MJupiter we
will use Kepler’s First law to find the center of gravity and
determine a binary orbit. Kepler’s First law states:
Comparing m (mass) with r (radius) to determine the center of
gravity in a binary system (R =1).
May 27, 2004
Acknowledgments
Observations
and the H-R Diagram
I would like to thank the following people for the help with my project:
The Hertzsprung-Russell Diagram
allows us to classify stars based
on their luminosity and surface
temperature. After finding
examples of many of the spectral
types through 20x80 binoculars, I
was able to more fully understand
the diagram itself. From my
research, I estimate Nemesis’
http://www.ulink.net/stargazerdan/star.html
surface temperature
to be close to 1500K. This chart does not show beyond the M
classification. But the next step down is called L. An L5 star, such
as a 19MJ Nemesis would be, would have the surface temperature
of 1500K and an absolute magnitude of +20.
My roommates at Evergreen, for putting up with my late nights sitting at the computer.
My classmates in Astronomy and Cosmologies, our friendships kept me in this class.
My classmates in Science Seminar, our discussions have greatly expanded my knowledge of the
universe.
The Evergreen State College, for furthering student’s knowledge of the sciences.
The Cooper Point Journal; Sophal, Renata, Katie, Rob, and Mitch, for putting up with my
astronomy articles, week after week.
E.J.Zita, my professor of Astronomy and Cosmologies.
My Parents, for funding my education.
Doug, Gene, and Nicole, Team 3 A&C class group.
Everyone else that I missed. Now try and blame me for missing you!
My friend Russell Allen, the Ronin of Bremerton, with whom I debate all my insane theories with.
Nemesis’ Magnitude
Assuming Nemesis has a 19MJ, with a surface temperature of
1500K, it’s location on the H-R diagram would classify it as a
spectral type L5. This would indicate that Nemesis would have an
absolute magnitude of close to +20.
To determine the value or r1, the distance the sun resides from
the center of gravity, we derive the formula to:
Using the values m2 = 1.72*1026 kg and r2 = 94860, we find r1 to
be 1.05 *10-5AU or 980 miles per 26 million years or about
2.3 inches per year.
The relationship between the apparent magnitude and the absolute
magnitude of an object is expressed as m-M = 5 log d-5, where m
is apparent magnitude, M is absolute magnitude, and d is distance
in parsecs. Knowing M = 20 and d = .5, we find that
m-20 = -5 log |.5-5| or m-20 = -3.26
From this we now know that the apparent magnitude of Nemesis
should be approximately magnitude 16. Far dimmer than can be
seen by the naked eye and beyond the limits of binoculars. Some
of the more powerful telescopes could see it. If they knew where
to look. Unfortunately, we have no evidence to determine an exact
orbit.
Acknowledgments
Bibliography
I would like to thank the following people for the help with my project:
Allen, Richard Hinckley. Star Names. General Publishing Co, Ltd., Toronto, Ontario, 1963.
My roommates at Evergreen, for putting up with my late nights
sitting at the computer.
Carroll, Bradley W. and Ostlie, Dale A. An Introduction to Modern Astrophysics. Addison-Wesley Publishing Company, Inc., Reading,
Massachusetts, 1996.
My classmates in Astronomy and Cosmologies and Science Seminar,
our discussions have greatly expanded my knowledge of the universe.
Maeder, André and Renzini, Alvio. eds. Observational Tests of the Stellar Evolution Theory, D. Reidel Publishing Company, Dordrecht, The
Netherlands, 1984.
The Cooper Point Journal; Sophal, Renata, Katie, Rob, and
Mitch, for putting up with my astronomy articles and the spellings of
ancient Greek words, week after week.
Shklovskii, Iosif S., Stars, Their Birth, Life, and Death. W.H. Freeman and Company, 1978
Gehrels, T. ed. Protostars & Planets. The University of Arizona Press, Tuscon, Arizona, 1978.
Raup, David M. The Nemesis Affair. W W Norton & Company, New York, London, 1999.
Smoluchowski, Roman, et al., eds. The Galaxy and the Solar System. The University of Arizona Press. Tuscan, Arizona. 1986.
Watt, Graeme D. and Williams, Peredur M. eds. Circumstellar Matter 1994. Kluwer Academic Publishers, Dordrecht, The Netherlands, 1995
Rose, William K, Advanced Stellar Astrophysics. Cambridge University Press. Cambridge, United Kingdom, 1998.
My Parents, for funding my education.
Russell Allen, the Ronin of Bremerton, with whom I discuss and
debate all my insane theories.
All those I have forgotten to mention, there is just so little space on
this one little slide.
Brown Dwarfs – Planet X. Phil Plait. 4 March 2003. May 2004
<www.BadAstronomy.com>
Dinosaurs Fried Within Hours, Study Concludes. Robert Roy Britt. Space.com. 26 May 2004. May 2004
< http://www.space.com/scienceastronomy/dinosaur_death_040526.html>
Asteroid Caused Earth’s Largest Mass Extinction. Space.com STAFF. Space.com. 29 August 2001. May 2004.
<http://www.space.com/scienceastronomy/solarsystem/permian_impact_010829.html>
Did and Impact Trigger the “Great Dying”? J. Kelly Beatty. Sky and Telescope.com, 14 May 2004. May 2004.
<http://skyandtelescope.com/news/article_1257_1.asp>
Properties of Stars. Nick Strobel. Astronomy Notes. 12 November 2002. May 2004
< http://www.astronomynotes.com/starprop/s4.htm>
Nemesis and Planet X. PlanetXVideo.com. May 2004
< http://www.planetxvideo.com/nemesis.htm>