American physicist (1925?2006)
George Wetherill
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Born
| (
1925-08-12
)
12 August 1925
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Died
| 19 July 2006
(2006-07-19)
(aged 80)
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Education
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Known for
| |
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Spouses
|
- Phyllis Steiss Wetherill
- Mary Bailey
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Children
| Rachel Wetherill
Sarah Wetherill Okumura
George W. Wetherill III
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Awards
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Scientific career
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Fields
| Astrophysics
,
Geology
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Institutions
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George Wetherill
(August 12, 1925 Philadelphia, Pennsylvania ? July 19, 2006 Washington, D.C.) was a physicist and geologist and the director emeritus of the department of terrestrial magnetism at the
Carnegie Institution of Washington
, DC, US.
[1]
[2]
In 2000, Wetherill received the
J. Lawrence Smith Medal
from the
National Academy of Sciences
"For his unique contributions to the cosmochronology of the planets and meteorites and to the orbital dynamics and formation of solar system bodies."
[3]
In 2003, Wetherill received the
Henry Norris Russell Lectureship
, the highest honor bestowed by the
American Astronomical Society
, "For pioneering the application of modern physics and numerical simulations to the formation and evolution of terrestrial planets."
[4]
Early life and education
[
edit
]
George Wetherill was born on August 12, 1925, in Philadelphia, Pennsylvania. Wetherill benefited from the
G.I. Bill
to receive four degrees, the Ph.B. (1948), S.B. (1949), S.M. (1951), and Ph.D., in physics (1953), all from the
University of Chicago
. He did his thesis research on the spontaneous
fission
of
uranium
, as well as nuclear processes in nature, as a
U.S. Atomic Energy Commission
Predoctoral Fellow.
[5]
Career and achievements
[
edit
]
Department of Terrestrial Magnetism, 1953-1960
[
edit
]
After receiving his Ph.D., Wetherill became a staff member at Carnegie's Department of Terrestrial Magnetism (DTM) in Washington, D.C. There, he joined an interdepartmental group who were working to date rocks using geochemical methods that measured natural
radioactive decay
. This involved determining the concentration and
isotopic
composition of
inert gases
such as
argon
, as well as the isotopes of
strontium
and
lead
.
[1]
Wetherill originated the concept of the Concordia Diagram for the uranium-lead isotopic system; this diagram became the standard means for determining precise ages of rocks, and of detecting the possibility of
metamorphism
. It provides a basis for high-precision
geochronology
of rocks dating back through the history of the planet Earth.
[1]
Wetherill was also a member of the Carnegie group that accurately determined the decay constants of
potassium
and
rubidium
, an effort that has also become fundamental to the measurement of geological time.
[1]
[6]
University of California, Los Angeles
[
edit
]
Wetherill left DTM in 1960 to become a professor of geophysics and geology at the
University of California, Los Angeles
. There, he served as chairman of the interdepartmental curriculum in geochemistry (1964-1968), and as chairman of the Department of Planetary and Space Sciences (1968-1972).
[7]
At UCLA, Wetherill further explored techniques for age-dating, examining extraterrestrial material with radiometric chronology techniques to
meteorite
and
lunar
samples. At the same time, he began to theorize about the origin of meteorites. His studies concentrated on collisions between objects in the
asteroid belt
together with resonances between their motions and those of planets. He computed how these events could move material into Earth-crossing orbits to become meteorites or larger Earth-impacting bodies responsible for the devastating impacts that caused mass extinctions of the majority of living species, including the dinosaurs.
[7]
Later, Wetherill, along with scientists elsewhere, proposed that a certain unusual class of meteorites was not asteroidal in origin but instead came from the planet
Mars
. This was later confirmed by laboratory work elsewhere and is now well accepted.
[7]
Department of Terrestrial Magnetism, 1975-
[
edit
]
In 1975, Wetherill returned to Carnegie's Department of Terrestrial Magnetism as director. He remained director until 1991, when he became a staff member. At DTM, he began extending his research efforts into questions concerning the origin of the terrestrial planets--
Mercury
,
Venus
,
Earth
, and
Mars
. He was stimulated by earlier studies by
Victor Safronov
(O. Yu. Schmidt Institute, Moscow), who showed that as a swarm of
planetesimals
coagulated into large bodies the swarm could evolve to produce a few terrestrial planets. Wetherill developed a technique to calculate numerically the orbital evolution and accumulation of planetesimal swarms, and he used the technique to reach specific predictions of the physical and orbital properties of terrestrial planets. His results agreed well with present observations.
[8]
In addition to showing how the inner solar system formed, Wetherill's work provided the basis for a model of a giant-impact origin for the
Moon
[9]
and the core of Mercury.
[10]
It also led to explanations for the isotopic abundances of present-day planetary atmospheres.
[11]
Wetherill has shown that
Jupiter
plays an important role in the evolution of the
Solar System
; by ejecting
comets
from the solar system, it offers a protective presence to the inner planets.
[7]
Wetherill's theoretical work supports discussions on the origins of the Solar System as well as on
extrasolar planets
.
[12]
[13]
Wetherill provided leadership in the scientific community by serving on advisory committees for
NASA
, the
National Academy of Sciences
,
[14]
and the
National Science Foundation
. For 15 years, he was editor of the
Annual Review of Earth and Planetary Sciences
.
[15]
He served as president of the
Meteoritical Society
, the
Geochemical Society
, the Planetology Section of the
American Geophysical Union
, the International Association of Geochemistry and Cosmochemistry,
[16]
and was a member of the
American Philosophical Society
.
[17]
Wetherill died at his home in Washington, D.C Wednesday, July 19, 2006, after a long illness.
[18]
[19]
Awards
[
edit
]
- 1974, Member,
National Academy of Sciences
[14]
[20]
- 1977,
National Medal of Science
,
National Science Foundation
[2]
- 1981,
Leonard Medal
,
Meteoritical Society
[21]
- 1984,
G. K. Gilbert Award
,
Geological Society of America
[22]
- 1986,
G. P. Kuiper Prize
of the Division of Planetary Sciences of the
American Astronomical Society
[23]
- 1991,
Harry H. Hess Medal
of the
American Geophysical Union
[24]
- 1997,
National Medal of Science
awarded by President Clinton
[25]
- 2000,
J. Lawrence Smith Medal
,
National Academy of Sciences
[3]
- 2003,
Henry Norris Russell Lectureship
, American Astronomical Society
[4]
External links
[
edit
]
References
[
edit
]
- ^
a
b
c
d
Pearce, Jeremy (2006-07-28).
"George W. Wetherill, 80, Expert on Dating of Rocks, Dies"
.
The New York Times
.
ISSN
0362-4331
.
Archived
from the original on 2021-11-17
. Retrieved
2021-08-18
.
- ^
a
b
"George W. Wetherill"
.
National Science and Technology Medals Foundation
.
Archived
from the original on 2021-11-17
. Retrieved
2021-08-18
.
- ^
a
b
"J. Lawrence Smith Medal"
.
National Academy of Sciences
.
Archived
from the original on 27 May 2016
. Retrieved
10 May
2022
.
- ^
a
b
"Henry Norris Russell Lectureship"
.
American Astronomical Society
.
Archived
from the original on 18 January 2021
. Retrieved
10 May
2022
.
- ^
"Wetherill, George West - Niels Bohr Library & Archives"
.
American Institute of Physics
.
Archived
from the original on 2021-05-17
. Retrieved
2021-08-18
.
- ^
Wetherill, George W. (1998).
"Contemplation of Things Past"
.
Annual Review of Earth and Planetary Sciences
.
26
(1): 1?21.
Bibcode
:
1998AREPS..26....1W
.
doi
:
10.1146/annurev.earth.26.1.1
.
ISSN
0084-6597
.
- ^
a
b
c
d
Holley, Joe (2006-07-22).
"George Wetherill"
.
Washington Post
.
ISSN
0190-8286
. Retrieved
2021-08-18
.
- ^
Henbest, Nigel.
"Science: Are there lots of Earths out there?"
.
New Scientist
.
Archived
from the original on 2021-08-18
. Retrieved
2021-08-18
.
- ^
Melosh, H. J. (13 September 2014).
"New approaches to the Moon's isotopic crisis"
.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
.
372
(2024): 20130168.
Bibcode
:
2014RSPTA.37230168M
.
doi
:
10.1098/rsta.2013.0168
.
PMC
4128260
.
PMID
25114301
.
- ^
Spalding, Christopher; Adams, Fred C. (1 March 2020).
"The Solar Wind Prevents Reaccretion of Debris after Mercury's Giant Impact"
.
The Planetary Science Journal
.
1
(1): 7.
arXiv
:
2002.07847
.
Bibcode
:
2020PSJ.....1....7S
.
doi
:
10.3847/psj/ab781f
.
ISSN
2632-3338
.
S2CID
211171488
.
- ^
Lupu, R. E.; Zahnle, Kevin; Marley, Mark S.;
Schaefer, Laura
; Fegley, Bruce; Morley, Caroline; Cahoy, Kerri; Freedman, Richard; Fortney, Jonathan J. (28 February 2014).
"The Atmospheres of Earthlike Planets After Giant Impact Events"
.
The Astrophysical Journal
.
784
(1): 27.
arXiv
:
1401.1499
.
Bibcode
:
2014ApJ...784...27L
.
doi
:
10.1088/0004-637x/784/1/27
.
hdl
:
1721.1/92946
.
ISSN
0004-637X
.
S2CID
10033333
.
Archived
from the original on 12 May 2022
. Retrieved
12 May
2022
.
- ^
Ksanfomaliti, L. V. (1 November 2000).
"Extrasolar Planetary Systems"
.
Solar System Research
.
34
(6): 481?495.
doi
:
10.1023/A:1005218112981
.
ISSN
1608-3423
.
S2CID
117713002
.
Archived
from the original on 12 May 2022
. Retrieved
12 May
2022
.
- ^
Wetherill, G. W. (1 January 1996).
"The Formation and Habitability of Extra-Solar Planets"
.
Icarus
.
119
(1): 219?238.
Bibcode
:
1996Icar..119..219W
.
doi
:
10.1006/icar.1996.0015
.
ISSN
0019-1035
.
Archived
from the original on 12 May 2022
. Retrieved
12 May
2022
.
- ^
a
b
"George W. Wetherill"
.
www.nasonline.org
.
Archived
from the original on 2021-12-07
. Retrieved
2021-12-07
.
- ^
Jeanloz, Raymond (May 1997).
"Preface"
.
Annual Review of Earth and Planetary Sciences
.
25
(1): annurev.ea.25.092506.100001.
doi
:
10.1146/annurev.ea.25.092506.100001
.
- ^
"NASA - NASA ASTROBIOLOGY INSTITUTE MEMBER GEORGE WETHERILL HONORED"
.
www.nasa.gov
. Archived from
the original
on 2021-08-18
. Retrieved
2021-08-18
.
- ^
"APS Member History"
.
search.amphilsoc.org
.
Archived
from the original on 2021-12-07
. Retrieved
2021-12-07
.
- ^
"George Wetherill"
.
www.lpi.usra.edu
.
Archived
from the original on 2021-07-30
. Retrieved
2021-08-18
.
- ^
"Father of Earth-formation models, Carnegie's George Wetherill, dies at 80"
.
Carnegie Institution for Science
. 21 July 2006.
Archived
from the original on 9 July 2022
. Retrieved
10 May
2022
.
- ^
"Science Academy Elects 96 Members"
.
The New York Times
. 28 April 1974.
Archived
from the original on 10 May 2022
. Retrieved
10 May
2022
.
- ^
"Leonard Medalists"
.
The Meteoritical Society
. Archived from
the original
on 29 June 2019
. Retrieved
10 May
2022
.
- ^
"G.K. Gilbert Award - Planetary Geology Division"
.
The Geological Society of America, Inc
.
Archived
from the original on 25 April 2022
. Retrieved
10 May
2022
.
- ^
"Gerard P. Kuiper Prize in Planetary Sciences | Division for Planetary Sciences"
.
American Astronomical Society
.
Archived
from the original on 29 October 2012
. Retrieved
10 May
2022
.
- ^
Anonymous (1992). "Wetherill receives 1991 Hess award".
Eos, Transactions American Geophysical Union
.
73
(12): 131.
doi
:
10.1029/91EO00111
.
- ^
"Recipients Of The 1997 National Medal Of Science"
.
clintonwhitehouse4.archives.gov
.
Archived
from the original on 9 December 2022
. Retrieved
10 May
2022
.