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President pro tempore of the United States Senate
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For a list of presidents pro tempore of the Senate, see List of Presidents pro tempore of the United States Senate.
President pro tempore of the United States Senate
Seal of the President pro tempore
Incumbent
Orrin Hatch (R)
since January 6, 2015
United States Senate
Style
Mr. President
(Informal and within the Senate)
The Honorable
(Formal)
Status
Deputy presiding officer
Seat
United States Capitol, Washington, D.C.
Appointer
United States Senate
Term length
At the pleasure of the Senate, and until another is elected or their term of office as a Senator expires
Constituting instrument
United States Constitution
Formation
March 4, 1789
First holder
John Langdon
April 6, 1789
Succession
Third[1]
Deputy
Any senator, typically a member of the majority party, designated by the President pro tempore
Website
www.senate.gov
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The President pro tempore of the United States Senate (often shortened to president pro tem) is the second-highest-ranking official of the United States Senate. Article One, Section Three of the United States Constitution provides that the Vice President of the United States is the President of the Senate (despite not being a Senator), and mandates that the Senate must choose a President pro tempore to act in the Vice President's absence. Unlike the Vice President, the President pro tempore is an elected member of the Senate, able to speak or vote on any issue. Selected by the Senate at large, the President pro tempore has enjoyed many privileges and some limited powers.[2] During the Vice President's absence, the President pro tempore is empowered to preside over Senate sessions. In practice, neither the Vice President nor the President pro tempore usually presides; instead, the duty of presiding officer is rotated among junior U.S. Senators of the majority party to give them experience in parliamentary procedure.[3]
Since 1890, the most senior U.S. Senator in the majority party has generally been chosen to be President pro tempore and holds the office continuously until the election of another. This tradition has been observed without interruption since 1949.[4] Since enactment of the current Presidential Succession Act in 1947, the president pro tempore is third in the line of succession to the presidency, after the vice president and the Speaker of the House of Representatives and ahead of the Secretary of State.[5]
The current President pro tempore of the Senate is Utah Republican Orrin Hatch. Elected on January 6, 2015,[6] he is the 90th person to serve in this office. On January 2, 2018, Hatch announced that he will retire from the Senate at the end of his current term, January 3, 2019.[7]
Contents
1 Power and responsibilities
2 History
3 Related officials
3.1 Acting president pro tempore
3.1.1 Permanent acting president pro tempore
3.2 Deputy president pro tempore
3.3 President pro tempore emeritus
4 Salary
5 See also
6 References
7 External links
Power and responsibilities[edit]
John Tyler is the only Senate president pro tempore to also become President of the United States.
Although the position is in some ways analogous to the Speaker of the House of Representatives, the powers of the president pro tempore are far more limited. In the Senate, most power rests with party leaders and individual senators, but as the chamber's presiding officer, the president pro tempore is authorized to perform certain duties in the absence of the vice president, including ruling on points of order.[8] Additionally, under the 25th Amendment to the Constitution, the president pro tempore and the speaker are the two authorities to whom declarations must be transmitted that the president is unable to perform the duties of the office, or is able to resume doing so. The president pro tempore is third in the line of presidential succession, following the vice president and the speaker.[8] Additional duties include appointment of various congressional officers, certain commissions, advisory boards, and committees and joint supervision of the congressional page school.[8] The president pro tempore is the designated legal recipient of various reports to the Senate, including War Powers Act reports under which he or she, jointly with the speaker, may have the president call Congress back into session. The officeholder is an ex officio member of various boards and commissions. With the secretary and sergeant at arms, the president pro tempore maintains order in Senate portions of the Capitol and Senate buildings.[8][9]
History[edit]
Benjamin Wade came within one vote of being the first president pro tempore to succeed to the presidency after the impeachment trial of Andrew Johnson in 1868
The office of president pro tempore was established by the Constitution of the United States in 1789. The first president pro tempore, John Langdon, was elected on April 6 the same year.[8] Between 1792 and 1886, the president pro tempore was second in the line of presidential succession following the vice president and preceding the speaker. Through 1891, the president pro tempore was appointed on an intermittent basis only, when the vice president was not present to preside over the Senate, or at the adjournment of a session of Congress.[10] Langdon served four separate terms from 1789 to 1793. During the 4th Congress (1795 – 1797); in all, more than a 12 senators held the office during the Senate’s first decade.[11] When called upon to serve, they would preside, sign legislation, and perform routine administrative tasks.
Whenever the vice presidency was vacant, as it was on 10 occasions between 1812 and 1889,[12] the office garnered heightened importance, for although he did not assume the vice presidency, the president pro was then next in line for the presidency.[13] Before the ratification of the Twenty-fifth Amendment in 1967, a vacancy in the vice presidency could be filled only by a regular election; several who served during these vacancies were referred to informally as "Acting Vice President."[14]
On three occasions during the 19th century, the Senate was without both a president and a president pro tempore:
July 9–11, 1850, following Millard Fillmore's accession to the presidency upon the death of Zachary Taylor, until William R. King was elected president pro tempore;[15]
September 19–October 10, 1881, following Chester Arthur's accession to the presidency upon the death of James A. Garfield, until Thomas F. Bayard was elected president pro tempore;[16]
November 25–December 7, 1885, following the death of Vice President Thomas A. Hendricks, until John Sherman was elected president pro tempore.[16]
President pro tempore Robert Byrd and House Speaker Dennis Hastert presided over a special joint session following the September 11, 2001, attacks. Here President Bush shakes hands with Byrd.
When President Andrew Johnson, who had no vice president, was impeached and tried in 1868, Senate President pro tempore Benjamin Franklin Wade was next in line to the presidency. Wade's radicalism is thought by many historians to be a major reason why the Senate, which did not want to see Wade in the White House, acquitted Johnson.[17] The President pro tempore and the Speaker of the House were removed from the presidential line of succession in 1886. Both were restored to it in 1947, though this time with the president pro tempore following the speaker.[8]
William P. Frye served as President pro tempore from 1896 to 1911 (54th–62nd Congress), a tenure longer than anyone else. He resigned from the position due to ill health a couple of months before his death. Electing his successor proved difficult, as Senate Republicans, then in the majority, were split between progressive and conservative factions, each promoting its own candidate. Likewise, the Democrats proposed their own candidate. As a result of this three-way split, no individual received a majority vote. It took four months for a compromise solution to emerge: Democrat Augustus Bacon would serve for a single day, August 14, 1911, during the vice president's absence. Thereafter, Bacon and four Republicans—Charles Curtis, Jacob Gallinger, Henry Cabot Lodge, and Frank Brandegee—would alternate as president pro tempore for the remainder of the Congress.[8]
In January 1945, the 79th Congress elected Kenneth McKellar, who at the time was the Senator with the longest continuous service, to be President pro tempore. Since then, it has become customary for the majority party's senior member to hold this position. Arthur Vandenberg (in 1947–1949) was the last president pro tempore not to be the senior member of the majority party, aside from the single day accorded Milton Young (in December 1980), who was the retiring senior member of the Republican Party, which would hold the majority in the incoming 97th Congress.[4]
Three presidents pro tempore subsequently became Vice President: John Tyler, William R. King and Charles Curtis. Tyler is the only one to become president (in April 1841, following the death of William Henry Harrison).
Related officials[edit]
Acting president pro tempore[edit]
President pro tempore Carl Hayden seated to the left of House Speaker John W. McCormick during a 1963 speech by President Lyndon B. Johnson to a joint session of Congress.
While the president pro tempore does have other official duties, the holders of the office have, like the vice president, over time ceased presiding over the Senate on a daily basis, owing to the mundane and ceremonial nature of the position.[10] Furthermore, as the president pro tempore is now usually the most senior senator of the majority party, he or she most likely also chairs a major Senate committee and has other significant demands on his or her time. Therefore, the president pro tempore has less time now than in the past to preside daily over the Senate. Instead, junior senators from the majority party are designated acting president pro tempore to preside over the Senate.[18] This allows junior senators to learn proper parliamentary procedure.[3] The acting president pro tempore is usually reappointed daily by the president pro tempore.[19]
Permanent acting president pro tempore[edit]
In June 1963, because of the illness of president pro tempore Carl Hayden, Senator Lee Metcalf was designated permanent acting president pro tempore. No term was imposed on this designation, so Metcalf retained it until he died in office in 1978.[9]
Deputy president pro tempore[edit]
Hubert Humphrey (D-Minnesota) was the first Deputy President pro tempore in 1977–1978
The ceremonial post of deputy president pro tempore was created for Hubert Humphrey, a former vice president, in 1977 following his losing bid to become the Senate majority leader.[20] The Senate resolution creating the position stated that any former president or former vice president serving in the Senate would be entitled to this position, though none has served since Humphrey's death in 1978,[9] and former vice president Walter Mondale, who sought his former Senate seat in Minnesota in 2002, is the only one to have tried. Andrew Johnson is the only former president (1865–1869) to have subsequently served in the Senate (1875).
George J. Mitchell was elected deputy president pro tempore in 1987, because of the illness of president pro tempore John C. Stennis, similar to Metcalf's earlier designation as permanent acting president pro tempore. The office has remained vacant since 1989 and no senator other than Humphrey and Mitchell has held it since its creation.[9] Mitchell is the only person to have served as deputy president pro tempore who was neither a former president nor former vice president of the United States.
The post is largely honorary and ceremonial, but comes with a salary increase. By statute, the compensation granted to the position holder equals the rate of annual compensation paid to the president pro tempore, majority leader, and minority leader. (See 2 U.S.C. § 6112.)[9]
President pro tempore emeritus[edit]
Patrick Leahy (D-Vermont), former president pro tempore, and current president pro tempore emeritus.
Since 2001, the honorary title of president pro tempore emeritus has been given to a senator of the minority party who has previously served as president pro tempore. The position has been held by Strom Thurmond (R-South Carolina) (2001–2003), Robert Byrd (D-West Virginia) (2003–2007), Ted Stevens (R-Alaska) (2007–2009) and Patrick Leahy (D-Vermont) (2015–present). From 2009 to 2015, no senator met the requirements for the position.
The position was created for Thurmond when the Democratic Party regained a majority in the Senate in June 2001.[21] With the change in party control, Democrat Robert Byrd of West Virginia replaced Thurmond as president pro tempore, reclaiming a position he had previously held from 1989 to 1995 and briefly in January 2001. Thurmond's retirement from the Senate on January 3, 2003, coincided with a change from Democratic to Republican control, making Stevens president pro tempore and Byrd the second president pro tempore emeritus. Byrd returned as president pro tempore, and Stevens became the third president pro tempore emeritus, when the Democrats gained control of the Senate in 2007.[9] While a president pro tempore emeritus has no official duties, he is entitled to an increase in staff[22] and advises party leaders on the functions of the Senate.
The office's accompanying budget increase was removed toward the end of the 113th Congress, shortly before Patrick Leahy was to become the first holder of the title in six years. Quoted in CQ Roll Call, Leahy commented, "[The Republicans] didn't keep their commitment. They want to treat us differently than we treated them, and so they've got that right. It seems kind of petty, but it really doesn't matter to me. I've got plenty of funding, plenty of good staff."[23]
Salary[edit]
The salary of the president pro tempore for 2012 was $193,400, equal to that of the majority leaders and minority leaders of both houses of Congress. If there is a vacancy in the office of vice president, then the salary would be the same as that of the vice president, $230,700.[9]
See also[edit]
Seniority in the United States Senate
References[edit]
Jump up ^ "3 U.S. Code § 19 - Vacancy in offices of both President and Vice President; officers eligible to act".
Jump up ^ Senate Historical Office; With a preface by Senator Robert C. Byrd, President pro tempore (2008). Erickson, Nancy (Secretary of the Senate), ed. Pro Tem: Presidents Pro Tempore of the United States Senate since 1789 (PDF). U.S. Government Printing Office. p. 9. ISBN 978-0-16-079984-6. Retrieved January 9, 2017.
^ Jump up to: a b "Hillary takes Senate gavel–for an hour". CNN. January 24, 2001. Archived from the original on January 20, 2010.
^ Jump up to: a b Davis, Christopher M. (December 20, 2012). The President Pro Tempore of the Senate: History and Authority of the Office (Report). Congressional Research Service. Retrieved February 23, 2015.
Jump up ^ Lord, Debbie (June 18, 2018). "A president resigns, dies or is impeached: What is the line of succession?". wftv.com. Cox Media Group. Retrieved June 18, 2018.
Jump up ^ Burr, Thomas (January 6, 2015). "Hatch now third in line for presidency as Senate president pro tem". The Salt Lake Tribune.
Jump up ^ Sullivan, Sean; Scherer, Michael (January 2, 2018). "Republican Sen. Orrin Hatch of Utah will retire, opening door for a Romney candidacy". The Washington Post. Retrieved January 3, 2017.
^ Jump up to: a b c d e f g "President Pro Tempore". United States Senate. Retrieved May 2, 2017.
^ Jump up to: a b c d e f g Sachs, Richard C. (January 22, 2003). "The President Pro Tempore of the Senate: History and Authority of the Office" (PDF). Congressional Research Service. Retrieved December 9, 2008.
^ Jump up to: a b Richard E. Berg-Andersson (June 7, 2001). "A Brief History of Congressional Leadership". The Green Papers. Retrieved November 17, 2009.
Jump up ^ Erickson, Nancy, ed. (August 22, 2008). "Chapter 1:The Formative Years, 1789–1860" (PDF). Pro tem : presidents pro tempore of the United States Senate since 1789. Washington, D.C.: U.S. Government Printing office. pp. 7–10. ISBN 978-0-16-079984-6. Retrieved July 12, 2018.
Jump up ^ Neale, Thomas H. (September 27, 2004). "Presidential and Vice Presidential Succession: Overview and Current Legislation" (PDF). CRS Report for Congress. Washington, D.C.: Congressional Research Service, the Library of Congress. p. 22. Retrieved June 16, 2018.
Jump up ^ "John Tyler, Tenth Vice President (1841)". Washington, D.C.: Office of the Secretary, United States Senate. Retrieved June 30, 2018.
Jump up ^ "Lafayette Foster". Art & History. Washington, D.C.: Secretary of the Senate. Retrieved July 12, 2018.
Jump up ^ Feerick, John D.; Freund, Paul A. (1965). From Failing Hands: the Story of Presidential Succession. New York City: Fordham University Press. pp. 104–105. LCCN 65-14917.
^ Jump up to: a b Erickson, Nancy, ed. (August 22, 2008). "Chapter 2: A Question of Succession, 1861-1889" (PDF). Pro tem : presidents pro tempore of the United States Senate since 1789. Washington, D.C.: U.S. Government Printing office. pp. 55–57. ISBN 978-0-16-079984-6. Retrieved July 12, 2018.
Jump up ^ Smith, Gene (1977). High Crimes and Misdemeanors: The Impeachment and Trial of Andrew Johnson. William Morrow & Company. ISBN 0-688-03072-6.
Jump up ^ Gold, Martin B.; Gupta, Dimple. "The Constitutional Option to Change Senate Rules and Procedures: A Majoritarian Means to Over Come the Filibuster*" (PDF). Harvard Journal of Law & Public Policy. 28 (1): 211.
Jump up ^ "APPOINTMENT OF A SENATOR TO THE CHAIR - Rules of the Senate - United States Senate Committee on Rules and Administration". Archived from the original on December 2, 2016.
Jump up ^ "Hubert H. Humphrey". virtualology.com. Evisum Inc. 2000. Retrieved December 24, 2009.
Jump up ^ S.Res. 103, adopted, June 6, 2001. "Thanking and Electing Strom Thurmond President pro tempore emeritus."
Jump up ^ 2 U.S.C. § 32b
Jump up ^ Lesniewski, Niels (December 10, 2014). "Leahy: 'Kind of Petty' Not to Fund Emeritus Office in 'Cromnibus'". CQ Roll Call. Retrieved January 7, 2015.
External links[edit]
"President pro tempore". Official website of the United States Senate. Retrieved November 27, 2008.
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President pro tempore of the Senate (Orrin Hatch)
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Secretary of Veterans Affairs (Robert Wilkie)
Secretary of Homeland Security (Kirstjen Nielsen)
* Ineligible to act as president
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Radiometric dating
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.[1] The use of radiometric dating was first published in 1907 by Bertram Boltwood[2] and is now the principal source of information about the absolute age of rocks and other geological features, including the age of fossilized life forms or the age of the Earth itself, and can also be used to date a wide range of natural and man-made materials.
Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geologic time scale.[3] Among the best-known techniques are radiocarbon dating, potassium–argon dating and uranium–lead dating. By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change. Radiometric dating is also used to date archaeological materials, including ancient artifacts.
Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.
Contents
[hide]
1 Fundamentals of radiometric dating
1.1 Radioactive decay
1.2 Accuracy of radiometric dating
1.3 Closure temperature
1.4 The age equation
2 Modern dating methods
2.1 Uranium–lead dating method
2.2 Samarium–neodymium dating method
2.3 Potassium–argon dating method
2.4 Rubidium–strontium dating method
2.5 Uranium–thorium dating method
2.6 Radiocarbon dating method
2.7 Fission track dating method
2.8 Chlorine-36 dating method
2.9 Luminescence dating methods
2.10 Other methods
3 Dating with short-lived extinct radionuclides
3.1 The 129I – 129Xe chronometer
3.2 The 26Al – 26Mg chronometer
4 See also
5 References
6 Further reading
Fundamentals of radiometric dating[edit]
Radioactive decay[edit]
Example of a radioactive decay chain from lead-212 (212Pb) to lead-208 (208Pb) . Each parent nuclide spontaneously decays into a daughter nuclide (the decay product) via an α decay or a β− decay. The final decay product, lead-208 (208Pb), is stable and can no longer undergo spontaneous radioactive decay.
All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus. Additionally, elements may exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus. A particular isotope of a particular element is called a nuclide. Some nuclides are inherently unstable. That is, at some point in time, an atom of such a nuclide will undergo radioactive decay and spontaneously transform into a different nuclide. This transformation may be accomplished in a number of different ways, including alpha decay (emission of alpha particles) and beta decay (electron emission, positron emission, or electron capture). Another possibility is spontaneous fission into two or more nuclides.
While the moment in time at which a particular nucleus decays is unpredictable, a collection of atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life, usually given in units of years when discussing dating techniques. After one half-life has elapsed, one half of the atoms of the nuclide in question will have decayed into a "daughter" nuclide or decay product. In many cases, the daughter nuclide itself is radioactive, resulting in a decay chain, eventually ending with the formation of a stable (nonradioactive) daughter nuclide; each step in such a chain is characterized by a distinct half-life. In these cases, usually the half-life of interest in radiometric dating is the longest one in the chain, which is the rate-limiting factor in the ultimate transformation of the radioactive nuclide into its stable daughter. Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., tritium) to over 100 billion years (e.g., samarium-147).[4]
For most radioactive nuclides, the half-life depends solely on nuclear properties and is essentially a constant. It is not affected by external factors such as temperature, pressure, chemical environment, or presence of a magnetic or electric field.[5][6][7] The only exceptions are nuclides that decay by the process of electron capture, such as beryllium-7, strontium-85, and zirconium-89, whose decay rate may be affected by local electron density. For all other nuclides, the proportion of the original nuclide to its decay products changes in a predictable way as the original nuclide decays over time. This predictability allows the relative abundances of related nuclides to be used as a clock to measure the time from the incorporation of the original nuclides into a material to the present.
Accuracy of radiometric dating[edit]
Thermal ionization mass spectrometer used in radiometric dating.
The basic equation of radiometric dating requires that neither the parent nuclide nor the daughter product can enter or leave the material after its formation. The possible confounding effects of contamination of parent and daughter isotopes have to be considered, as do the effects of any loss or gain of such isotopes since the sample was created. It is therefore essential to have as much information as possible about the material being dated and to check for possible signs of alteration.[8] Precision is enhanced if measurements are taken on multiple samples from different locations of the rock body. Alternatively, if several different minerals can be dated from the same sample and are assumed to be formed by the same event and were in equilibrium with the reservoir when they formed, they should form an isochron. This can reduce the problem of contamination. In uranium–lead dating, the concordia diagram is used which also decreases the problem of nuclide loss. Finally, correlation between different isotopic dating methods may be required to confirm the age of a sample. For example, the age of the Amitsoq gneisses from western Greenland was determined to be 3.6 ± 0.05 million years ago (MA) using uranium–lead dating and 3.56 ± 0.10 Ma using lead–lead dating, results that are consistent with each other.[9]:142–143
Accurate radiometric dating generally requires that the parent has a long enough half-life that it will be present in significant amounts at the time of measurement (except as described below under "Dating with short-lived extinct radionuclides"), the half-life of the parent is accurately known, and enough of the daughter product is produced to be accurately measured and distinguished from the initial amount of the daughter present in the material. The procedures used to isolate and analyze the parent and daughter nuclides must be precise and accurate. This normally involves isotope-ratio mass spectrometry.[10]
The precision of a dating method depends in part on the half-life of the radioactive isotope involved. For instance, carbon-14 has a half-life of 5,730 years. After an organism has been dead for 60,000 years, so little carbon-14 is left that accurate dating can not be established. On the other hand, the concentration of carbon-14 falls off so steeply that the age of relatively young remains can be determined precisely to within a few decades.[11]
Closure temperature[edit]
Main article: Closure temperature
If a material that selectively rejects the daughter nuclide is heated, any daughter nuclides that have been accumulated over time will be lost through diffusion, setting the isotopic "clock" to zero. The temperature at which this happens is known as the closure temperature or blocking temperature and is specific to a particular material and isotopic system. These temperatures are experimentally determined in the lab by artificially resetting sample minerals using a high-temperature furnace. As the mineral cools, the crystal structure begins to form and diffusion of isotopes is less easy. At a certain temperature, the crystal structure has formed sufficiently to prevent diffusion of isotopes. This temperature is what is known as closure temperature and represents the temperature below which the mineral is a closed system to isotopes. Thus an igneous or metamorphic rock or melt, which is slowly cooling, does not begin to exhibit measurable radioactive decay until it cools below the closure temperature. The age that can be calculated by radiometric dating is thus the time at which the rock or mineral cooled to closure temperature.[12][13] Dating of different minerals and/or isotope systems (with differing closure temperatures) within the same rock can therefore enable the tracking of the thermal history of the rock in question with time, and thus the history of metamorphic events may become known in detail. This field is known as thermochronology or thermochronometry.
The age equation[edit]
Sm/Nd isochron plotted of samples [14] from the Great Dyke, Zimbabwe. The age is calculated from the slope of the isochron (line) and the original composition from the intercept of the isochron with the y-axis.
The mathematical expression that relates radioactive decay to geologic time is[12][15]
D = D0 + N(t) (eλt − 1)
where
t is age of the sample,
D is number of atoms of the daughter isotope in the sample,
D0 is number of atoms of the daughter isotope in the original composition,
N is number of atoms of the parent isotope in the sample at time t (the present), given by N(t) = Noe-λt, and
λ is the decay constant of the parent isotope, equal to the inverse of the radioactive half-life of the parent isotope[16] times the natural logarithm of 2.
The equation is most conveniently expressed in terms of the measured quantity N(t) rather than the constant initial value No.
The above equation makes use of information on the composition of parent and daughter isotopes at the time the material being tested cooled below its closure temperature. This is well-established for most isotopic systems.[13][17] However, construction of an isochron does not require information on the original compositions, using merely the present ratios of the parent and daughter isotopes to a standard isotope. Plotting an isochron is used to solve the age equation graphically and calculate the age of the sample and the original composition.
Modern dating methods[edit]
Radiometric dating has been carried out since 1905 when it was invented by Ernest Rutherford as a method by which one might determine the age of the Earth. In the century since then the techniques have been greatly improved and expanded.[16] Dating can now be performed on samples as small as a nanogram using a mass spectrometer. The mass spectrometer was invented in the 1940s and began to be used in radiometric dating in the 1950s. It operates by generating a beam of ionized atoms from the sample under test. The ions then travel through a magnetic field, which diverts them into different sampling sensors, known as "Faraday cups", depending on their mass and level of ionization. On impact in the cups, the ions set up a very weak current that can be measured to determine the rate of impacts and the relative concentrations of different atoms in the beams.
Uranium–lead dating method[edit]
Main article: Uranium–lead dating
A concordia diagram as used in uranium–lead dating, with data from the Pfunze Belt, Zimbabwe.[18] All the samples show loss of lead isotopes, but the intercept of the errorchron (straight line through the sample points) and the concordia (curve) shows the correct age of the rock.[13]
Uranium–lead radiometric dating involves using uranium-235 or uranium-238 to date a substance's absolute age. This scheme has been refined to the point that the error margin in dates of rocks can be as low as less than two million years in two-and-a-half billion years.[14][19] An error margin of 2–5% has been achieved on younger Mesozoic rocks.[20]
Uranium–lead dating is often performed on the mineral zircon (ZrSiO4), though it can be used on other materials, such as baddeleyite, as well as monazite (see: monazite geochronology).[21] Zircon and baddeleyite incorporate uranium atoms into their crystalline structure as substitutes for zirconium, but strongly reject lead. Zircon has a very high closure temperature, is resistant to mechanical weathering and is very chemically inert. Zircon also forms multiple crystal layers during metamorphic events, which each may record an isotopic age of the event. In situ micro-beam analysis can be achieved via laser ICP-MS or SIMS techniques.[22]
One of its great advantages is that any sample provides two clocks, one based on uranium-235's decay to lead-207 with a half-life of about 700 million years, and one based on uranium-238's decay to lead-206 with a half-life of about 4.5 billion years, providing a built-in crosscheck that allows accurate determination of the age of the sample even if some of the lead has been lost. This can be seen in the concordia diagram, where the samples plot along an errorchron (straight line) which intersects the concordia curve at the age of the sample.
Samarium–neodymium dating method[edit]
Main article: Samarium–neodymium dating
This involves the alpha decay of 147Sm to 143Nd with a half-life of 1.06 x 1011 years. Accuracy levels of within twenty million years in ages of two-and-a-half billion years are achievable.[23]
Potassium–argon dating method[edit]
Main article: Potassium–argon dating
This involves electron capture or positron decay of potassium-40 to argon-40. Potassium-40 has a half-life of 1.3 billion years, and so this method is applicable to the oldest rocks. Radioactive potassium-40 is common in micas, feldspars, and hornblendes, though the closure temperature is fairly low in these materials, about 350 °C (mica) to 500 °C (hornblende).
Rubidium–strontium dating method[edit]
Main article: Rubidium–strontium dating
This is based on the beta decay of rubidium-87 to strontium-87, with a half-life of 50 billion years. This scheme is used to date old igneous and metamorphic rocks, and has also been used to date lunar samples. Closure temperatures are so high that they are not a concern. Rubidium-strontium dating is not as precise as the uranium-lead method, with errors of 30 to 50 million years for a 3-billion-year-old sample.
Uranium–thorium dating method[edit]
Main article: Uranium–thorium dating
A relatively short-range dating technique is based on the decay of uranium-234 into thorium-230, a substance with a half-life of about 80,000 years. It is accompanied by a sister process, in which uranium-235 decays into protactinium-231, which has a half-life of 32,760 years.
While uranium is water-soluble, thorium and protactinium are not, and so they are selectively precipitated into ocean-floor sediments, from which their ratios are measured. The scheme has a range of several hundred thousand years. A related method is ionium–thorium dating, which measures the ratio of ionium (thorium-230) to thorium-232 in ocean sediment.
Radiocarbon dating method[edit]
Main article: Radiocarbon dating
Ale's Stones at Kåseberga, around ten kilometres south east of Ystad, Sweden were dated at 56 CE using the carbon-14 method on organic material found at the site.[24]
Radiocarbon dating is also simply called Carbon-14 dating. Carbon-14 is a radioactive isotope of carbon, with a half-life of 5,730 years,[25][26] (which is very short compared with the above isotopes) and decays into nitrogen.[27] In other radiometric dating methods, the heavy parent isotopes were produced by nucleosynthesis in supernovas, meaning that any parent isotope with a short half-life should be extinct by now. Carbon-14, though, is continuously created through collisions of neutrons generated by cosmic rays with nitrogen in the upper atmosphere and thus remains at a near-constant level on Earth. The carbon-14 ends up as a trace component in atmospheric carbon dioxide (CO2).
A carbon-based life form acquires carbon during its lifetime. Plants acquire it through photosynthesis, and animals acquire it from consumption of plants and other animals. When an organism dies, it ceases to take in new carbon-14, and the existing isotope decays with a characteristic half-life (5730 years). The proportion of carbon-14 left when the remains of the organism are examined provides an indication of the time elapsed since its death. This makes carbon-14 an ideal dating method to date the age of bones or the remains of an organism. The carbon-14 dating limit lies around 58,000 to 62,000 years.[28]
The rate of creation of carbon-14 appears to be roughly constant, as cross-checks of carbon-14 dating with other dating methods show it gives consistent results. However, local eruptions of volcanoes or other events that give off large amounts of carbon dioxide can reduce local concentrations of carbon-14 and give inaccurate dates. The releases of carbon dioxide into the biosphere as a consequence of industrialization have also depressed the proportion of carbon-14 by a few percent; conversely, the amount of carbon-14 was increased by above-ground nuclear bomb tests that were conducted into the early 1960s. Also, an increase in the solar wind or the Earth's magnetic field above the current value would depress the amount of carbon-14 created in the atmosphere.
Fission track dating method[edit]
Main article: fission track dating
Apatite crystals are widely used in fission track dating.
This involves inspection of a polished slice of a material to determine the density of "track" markings left in it by the spontaneous fission of uranium-238 impurities. The uranium content of the sample has to be known, but that can be determined by placing a plastic film over the polished slice of the material, and bombarding it with slow neutrons. This causes induced fission of 235U, as opposed to the spontaneous fission of 238U. The fission tracks produced by this process are recorded in the plastic film. The uranium content of the material can then be calculated from the number of tracks and the neutron flux.
This scheme has application over a wide range of geologic dates. For dates up to a few million years micas, tektites (glass fragments from volcanic eruptions), and meteorites are best used. Older materials can be dated using zircon, apatite, titanite, epidote and garnet which have a variable amount of uranium content.[29] Because the fission tracks are healed by temperatures over about 200 °C the technique has limitations as well as benefits. The technique has potential applications for detailing the thermal history of a deposit.
Chlorine-36 dating method[edit]
Large amounts of otherwise rare 36Cl (half-life ~300ky) were produced by irradiation of seawater during atmospheric detonations of nuclear weapons between 1952 and 1958. The residence time of 36Cl in the atmosphere is about 1 week. Thus, as an event marker of 1950s water in soil and ground water, 36Cl is also useful for dating waters less than 50 years before the present. 36Cl has seen use in other areas of the geological sciences, including dating ice and sediments.
Luminescence dating methods[edit]
Main article: Luminescence dating
Luminescence dating methods are not radiometric dating methods in that they do not rely on abundances of isotopes to calculate age. Instead, they are a consequence of background radiation on certain minerals. Over time, ionizing radiation is absorbed by mineral grains in sediments and archaeological materials such as quartz and potassium feldspar. The radiation causes charge to remain within the grains in structurally unstable "electron traps". Exposure to sunlight or heat releases these charges, effectively "bleaching" the sample and resetting the clock to zero. The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried. Stimulating these mineral grains using either light (optically stimulated luminescence or infrared stimulated luminescence dating) or heat (thermoluminescence dating) causes a luminescence signal to be emitted as the stored unstable electron energy is released, the intensity of which varies depending on the amount of radiation absorbed during burial and specific properties of the mineral.
These methods can be used to date the age of a sediment layer, as layers deposited on top would prevent the grains from being "bleached" and reset by sunlight. Pottery shards can be dated to the last time they experienced significant heat, generally when they were fired in a kiln.
Other methods[edit]
Other methods include:
argon–argon (Ar–Ar)
iodine–xenon (I–Xe)
lanthanum–barium (La–Ba)
lead–lead (Pb–Pb)
lutetium–hafnium (Lu–Hf)
potassium–calcium (K–Ca)
rhenium–osmium (Re–Os)
uranium–lead–helium (U–Pb–He)
uranium–uranium (U–U)
krypton–krypton (Kr–Kr)
Dating with short-lived extinct radionuclides[edit]
Absolute radiometric dating requires a measurable fraction of parent nucleus to remain in the sample rock. For rocks dating back to the beginning of the solar system, this requires extremely long-lived parent isotopes, making measurement of such rocks' exact ages imprecise. To be able to distinguish the relative ages of rocks from such old material, and to get a better time resolution than that available from long-lived isotopes, short-lived isotopes that are no longer present in the rock can be used.[30]
At the beginning of the solar system, there were several relatively short-lived radionuclides like 26Al, 60Fe, 53Mn, and 129I present within the solar nebula. These radionuclides—possibly produced by the explosion of a supernova—are extinct today, but their decay products can be detected in very old material, such as that which constitutes meteorites. By measuring the decay products of extinct radionuclides with a mass spectrometer and using isochronplots, it is possible to determine relative ages of different events in the early history of the solar system. Dating methods based on extinct radionuclides can also be calibrated with the U-Pb method to give absolute ages. Thus both the approximate age and a high time resolution can be obtained. Generally a shorter half-life leads to a higher time resolution at the expense of timescale.
The 129I – 129Xe chronometer[edit]
See also: Iodine-129 § Meteorite age dating
129I beta-decays to 129Xe with a half-life of 16 million years. The iodine-xenon chronometer[31] is an isochron technique. Samples are exposed to neutrons in a nuclear reactor. This converts the only stable isotope of iodine (127I) into 128Xe via neutron capture followed by beta decay (of 128I). After irradiation, samples are heated in a series of steps and the xenon isotopic signature of the gas evolved in each step is analysed. When a consistent 129Xe/128Xe ratio is observed across several consecutive temperature steps, it can be interpreted as corresponding to a time at which the sample stopped losing xenon.
Samples of a meteorite called Shallowater are usually included in the irradiation to monitor the conversion efficiency from 127I to 128Xe. The difference between the measured 129Xe/128Xe ratios of the sample and Shallowater then corresponds to the different ratios of 129I/127I when they each stopped losing xenon. This in turn corresponds to a difference in age of closure in the early solar system.
The 26Al – 26Mg chronometer[edit]
Another example of short-lived extinct radionuclide dating is the 26Al – 26Mg chronometer, which can be used to estimate the relative ages of chondrules. 26Al decays to 26Mg with a half-life of 720 000 years. The dating is simply a question of finding the deviation from the natural abundance of 26Mg (the product of 26Al decay) in comparison with the ratio of the stable isotopes 27Al/24Mg.
The excess of 26Mg (often designated 26Mg* ) is found by comparing the 26Mg/27Mg ratio to that of other Solar System materials.[32]
The 26Al – 26Mg chronometer gives an estimate of the time period for formation of primitive meteorites of only a few million years (1.4 million years for Chondrule formation).[33]
See also[edit]
Hadean zircon
Isochron dating
Isotope geochemistry
Isotopic signature
Paleopedological record
Radioactivity
Radiohalo
Sensitive High Resolution Ion Microprobe (SHRIMP)
References[edit]
Jump up ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "radioactive dating".
Jump up ^ Boltwood, Bertram (1907). "The Ultimate Disintegration Products of the Radio-active Elements. Part II. The disintegration products of uranium". American Journal of Science. 4. 23 (134): 77–88. doi:10.2475/ajs.s4-23.134.78.
Jump up ^ McRae, A. 1998. Radiometric Dating and the Geological Time Scale: Circular Reasoning or Reliable Tools? Radiometric Dating and the Geological Time Scale TalkOrigins Archive
Jump up ^ Bernard-Griffiths, J.; Groan, G. (1989). "The samarium–neodymium method". In Roth, Etienne; Poty, Bernard. Nuclear Methods of Dating. Springer Netherlands. pp. 53 – 72. ISBN 978-0-7923-0188-2.
Jump up ^ Emery, G T (1972). "Perturbation of Nuclear Decay Rates". Annual Review of Nuclear Science. 22 (1): 165–202. Bibcode:1972ARNPS..22..165E. doi:10.1146/annurev.ns.22.120172.001121.
Jump up ^ Shlyakhter, A. I. (1976). "Direct test of the constancy of fundamental nuclear constants". Nature. 264 (5584): 340. Bibcode:1976Natur.264..340S. doi:10.1038/264340a0.
Jump up ^ Johnson, B. 1993. How to Change Nuclear Decay Rates Usenet Physics FAQ
Jump up ^ Stewart, K,, Turner, S, Kelley, S, Hawkesworh, C Kristein, L and Manotvani, M (1996). "3-D, 40Ar---39Ar geochronology in the Paraná continental flood basalt province". Earth and Planetary Science Letters. 143 (1–4): 95–109. Bibcode:1996E&PSL.143...95S. doi:10.1016/0012-821X(96)00132-X. CS1 maint: Multiple names: authors list (link)
Jump up ^ Dalrymple, G. Brent (1994). The age of the earth. Stanford, Calif.: Stanford Univ. Press. ISBN 9780804723312.
Jump up ^ Dickin, Alan P. (2008). Radiogenic isotope geology (2nd ed.). Cambridge: Cambridge Univ. Press. pp. 15–49. ISBN 9780521530170.
Jump up ^ Reimer Paula J, et al. (2004). "INTCAL04 Terrestrial Radiocarbon Age Calibration, 0–26 Cal Kyr BP" (PDF). Radiocarbon. 46 (3): 1029–1058.
^ Jump up to: a b Faure, Gunter (1998). Principles and applications of geochemistry: a comprehensive textbook for geology students (2nd ed.). Englewood Cliffs, New Jersey: Prentice Hall. ISBN 0-02-336450-5. OCLC 37783103. [page needed]
^ Jump up to: a b c Rollinson, Hugh R. (1993). Using geochemical data: evaluation, presentation, interpretation. Harlow: Longman. ISBN 0-582-06701-4. OCLC 27937350. [page needed]
^ Jump up to: a b Oberthür, T, Davis, DW, Blenkinsop, TG, Hoehndorf, A (2002). "Precise U–Pb mineral ages, Rb–Sr and Sm–Nd systematics for the Great Dyke, Zimbabwe—constraints on late Archean events in the Zimbabwe craton and Limpopo belt". Precambrian Research. 113 (3–4): 293–306. Bibcode:2002PreR..113..293O. doi:10.1016/S0301-9268(01)00215-7. CS1 maint: Multiple names: authors list (link)
Jump up ^ White, W. M. (2003). "Basics of Radioactive Isotope Geochemistry" (PDF). Cornell University.
^ Jump up to: a b "Geologic Time: Radiometric Time Scale". United States Geological Survey. 16 June 2001.
Jump up ^ Stacey, J. S.; J. D. Kramers (June 1975). "Approximation of terrestrial lead isotope evolution by a two-stage model". Earth and Planetary Science Letters. 26 (2): 207–221. Bibcode:1975E&PSL..26..207S. doi:10.1016/0012-821X(75)90088-6.
Jump up ^ Vinyu, M. L.; R. E. Hanson; M. W. Martin; S. A. Bowring; H. A. Jelsma; P. H. G. M. Dirks (2001). "U-Pb zircon ages from a craton-margin archaean orogenic belt in northern Zimbabwe". Journal of African Earth Sciences. 32 (1): 103–114. Bibcode:2001JAfES..32..103V. doi:10.1016/S0899-5362(01)90021-1.
Jump up ^ Manyeruke, Tawanda D.; Thomas G. Blenkinsop; Peter Buchholz; David Love; Thomas Oberthür; Ulrich K. Vetter; Donald W. Davis (2004). "The age and petrology of the Chimbadzi Hill Intrusion, NW Zimbabwe: first evidence for early Paleoproterozoic magmatism in Zimbabwe". Journal of African Earth Sciences. 40 (5): 281–292. Bibcode:2004JAfES..40..281M. doi:10.1016/j.jafrearsci.2004.12.003.
Jump up ^ Li, Xian-hua; Liang, Xi-rong; Sun, Min; Guan, Hong; Malpas, J. G. (2001). "Precise 206Pb/238U age determination on zircons by laser ablation microprobe-inductively coupled plasma-mass spectrometry using continuous linear ablation". Chemical Geology. 175 (3–4): 209–219. Bibcode:2001ChGeo.175..209L. doi:10.1016/S0009-2541(00)00394-6.
Jump up ^ Wingate, M.T.D. (2001). "SHRIMP baddeleyite and zircon ages for an Umkondo dolerite sill, Nyanga Mountains, Eastern Zimbabwe". South African Journal of Geology. 104 (1): 13–22. doi:10.2113/104.1.13.
Jump up ^ Ireland, Trevor (December 1999). "Isotope Geochemistry: New Tools for Isotopic Analysis". Science. 286 (5448): 2289–2290. doi:10.1126/science.286.5448.2289.
Jump up ^ Mukasa, S. B.; A. H. Wilson; R. W. Carlson (December 1998). "A multielement geochronologic study of the Great Dyke, Zimbabwe: significance of the robust and reset ages". Earth and Planetary Science Letters. 164 (1–2): 353–369. Bibcode:1998E&PSL.164..353M. doi:10.1016/S0012-821X(98)00228-3.
Jump up ^ "Ales stenar". The Swedish National Heritage Board. 11 October 2006. Retrieved 9 March 2009.
Jump up ^ Clark, R. M. (1975). "A calibration curve for radiocarbon dates". Antiquity. 49: 251–266.
Jump up ^ Vasiliev, S. S.; V. A. Dergachev (2002). "The ~2400-year cycle in atmospheric radiocarbon concentration: Bispectrum of 14C data over the last 8000 years" (PDF). Annales Geophysicae. 20 (1): 115–120. Bibcode:2002AnGeo..20..115V. doi:10.5194/angeo-20-115-2002.
Jump up ^ "Carbon-14 Dating". www.chem.uwec.edu. Retrieved 2016-04-06.
Jump up ^ Plastino, Wolfango; Lauri Kaihola; Paolo Bartolomei; Francesco Bella (2001). "Cosmic background reduction in the radiocarbon measurement by scintillation spectrometry at the underground laboratory of Gran Sasso" (PDF). Radiocarbon. 43 (2A): 157–161.
Jump up ^ Jacobs, J.; R. J. Thomas (August 2001). "A titanite fission track profile across the southeastern Archæan Kaapvaal Craton and the Mesoproterozoic Natal Metamorphic Province, South Africa: evidence for differential cryptic Meso- to Neoproterozoic tectonism". Journal of African Earth Sciences. 33 (2): 323–333. Bibcode:2001JAfES..33..323J. doi:10.1016/S0899-5362(01)80066-X.
Jump up ^ Imke de Pater and Jack J. Lissauer: Planetary Sciences, page 321. Cambridge University Press, 2001. ISBN 0-521-48219-4
Jump up ^ Gilmour, J. D.; O. V Pravdivtseva; A. Busfield; C. M. Hohenberg (2006). "The I-Xe Chronometer and the Early Solar System". Meteoritics and Planetary Science. 41: 19–31. Bibcode:2006M&PS...41...19G. doi:10.1111/j.1945-5100.2006.tb00190.x. Retrieved 2013-01-21.
Jump up ^ Alexander N. Krot(2002) Dating the Earliest Solids in our Solar System, Hawai'i Institute of Geophysics and Planetology http://www.psrd.hawaii.edu/Sept02/isotopicAges.html.
Jump up ^ Imke de Pater and Jack J. Lissauer: Planetary Sciences, page 322. Cambridge University Press, 2001. ISBN 0-521-48219-4
Further reading[edit]
Gunten, Hans R. von (1995). "Radioactivity: A Tool to Explore the Past". Radiochimica Acta. 70-71 (s1). doi:10.1524/ract.1995.7071.special-issue.305. ISSN 2193-3405.
Magill, Joseph; Galy, Jean (2005). "Archaeology and Dating". Radioactivity Radionuclides Radiation. Springer Berlin Heidelberg. pp. 105–115. doi:10.1007/3-540-26881-2_6. ISBN 978-3-540-26881-9.
Isotope Geology. ISBN 978-0521862288.
Geochemistry: Pathways and Processes (2 ed.). ISBN 0-231-12440-6.
Cosmochemistry. ISBN 978-0-521-87862-3.
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Fearless (TV series)
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Fearless
Genre
Crime thriller
Created by
Patrick Harbinson
Written by
Patrick Harbinson
Directed by
Pete Travis
Creative director(s)
Rebecca Keane
Starring
Helen McCrory
Wunmi Mosaku
Jonathan Forbes
Sam Swainsbury
John Bishop
Jack Shepherd
Kika Markham
Rick Warden
Alec Newman
Rebecca Callard
Allan Corduner
Jemima Rooper
Robin Weigert
Michael Gambon
Jamie Bamber
Emma Hamilton
Country of origin
United Kingdom
Original language(s)
English
No. of series
1
No. of episodes
6 (list of episodes)
Production
Executive producer(s)
Patrick Harbinson
Damien Timmer
Tom Mullens
Producer(s)
Adrian Sturges
Location(s)
London, England
Editor(s)
Matt Platt-Mills
Sigvaldi J. Karason
Malcolm Crowe
Running time
45 minutes
Production company(s)
Mammoth Screen
Distributor
ITV Studios Global Entertainment
Release
Original network
ITV
Picture format
18:9 (1080i)
Audio format
Stereo
Original release
12 June 2017 (2017-06-12) – present
Fearless is a six-part British crime thriller television drama series, created by screenwriter Patrick Harbinson.[1] The series follows human rights lawyer Emma Banville (Helen McCrory), as she attempts to prove convicted murderer Kevin Russell innocent of the murder of schoolgirl Linda Simms 14 years ago. Kevin proclaims his innocence of the crime, and Emma, believing a miscarriage of justice has occurred, goes to extreme lengths to discover the truth.[2]
Supporting cast includes Michael Gambon as influential former Deputy Secretary to the Cabinet Office Sir Alastair McKinnon, Jonathan Forbes as Emma's colleague Dominic Truelove, Wunmi Mosaku as DCS Olivia Greenwood, the Investigating Officer on the Linda Simms case, and John Bishop as Emma's boyfriend Steve Livesey.[3]
Filming for the series began in September 2016 in London and East Anglia.[4] The series debuted on ITV in the UK on 12 June 2017. The series received positive reviews, with critics praising Helen McCrory's performance.[5][6]
Contents
[hide]
1 Cast
1.1 Main cast
1.2 Supporting cast
2 Episodes
3 References
4 External links
Cast[edit]
Main cast[edit]
Helen McCrory as Emma Banville, a successful human rights lawyer
Jonathan Forbes as Dominic Truelove, a former police officer and Banville's legal assistant
Sam Swainsbury as Kevin Russell, a man wrongly imprisoned for 14 years for the murder of Linda Simms
Rebecca Callard as Annie Peterson, Kevin's former girlfriend and the mother of his son
Wunmi Mosaku as DCS Olivia Greenwood, a Counter Terrorism Command officer who previously led the Simms murder investigation
Robin Weigert as Heather Myles, a Central Intelligence Agency operative
John Bishop as Steve Livesey, Banville's photographer boyfriend
Jamie Bamber as Matthew Wild MP, a young politician and former soldier who later becomes Leader of the Opposition
Emma Hamilton as Rachel Leigh/Laura Wild, a childhood friend of Linda Simms and the wife of Matthew Wild
Michael Gambon as Sir Alastair McKinnon, the former Deputy Secretary to the Cabinet under Prime Minister Tony Blair.
Supporting cast[edit]
Rick Warden as Charlie Simms, father of Linda Simms
Cathy Murphy as Beth Simms, mother of Linda Simms
Ben Cartwright as Phil Simms, uncle of Linda Simms
Jack Hollington as Jason Russell-Peterson, the 14 year old son of Kevin Russell and Annie Peterson
Christine Bottomley as DS Jenna Brooks, a Counter Terrorism Command officer
Karima McAdams as Miriam Attar, the wife of a suspected terrorist and friend of Banville
Alec Newman as Tony Pullings, a media photographer involved in the conspiracy
Allan Corduner as Monty Berman
Jemima Rooper as Maggie Berman
David Menkin as Sergeant Marcus
Brendan Patricks as DCI Nicholas Staines, a Metropolitan Police Service detective
Eve Austin as Linda Simms, the 15 year old girl Kevin Russell was wrongly accused of killing
Armin Karima as Imran
Colin Stinton as Jack Kretchmer, the former US Under Secretary of Defense under President George W. Bush
Catherine Steadman as Karen Buxton
David Mumeni as Hamid
Dhaffer L'Abidine as Dr. Yusef Attar, one of Banville's clients suspected of having ties to ISIS
Amra Mallassi as Ramzi
Tim McMullan as David Nolenn
Pandora Clifford as Nicola Osborne
Jack Shepherd as Arthur Banville, Emma's terminally ill father
Kika Markham as Eleanor Banville, Emma's mother
James Thorne as Derek Peterson, Annie's husband and Jason's stepfather
Sam Crane as Luke
Brian Caspe as Joel Fugard
Anna Berentzen as Young Emma
Sammy Winward as Siobhan Murphy
Damian Quinn as Hugh Godfrey
Suzette Llewellyn as Delilah Hamlin
Corey Johnson as Larry Arlman, an American private investigator used by Banville and her colleagues
Jonah Lotan as Logan Bradley, a member of the United States Air Force previously romantically involved with Linda Simms
Episodes[edit]
No.
Title
Directed by
Written by
Original air date
UK viewers
(millions)
1
"Episode 1" Pete Travis Patrick Harbinson 12 June 2017 (2017-06-12) 7.16
Criminal lawyer Emma Banville takes up the case of convicted killer Kevin Russell, who is serving life for the murder of 15-year-old schoolgirl Linda Simms fourteen years ago. But as the press get wind of Emma's intentions, Kevin's safety is placed in grave danger. Despite the conviction getting overturned, Kevin faces the harrowing event of a re-trial, and Emma faces the wrath of the original investigator, Olivia Greenwood. Events in Emma's personal life fail to make the case any easier. While taking care of the wife of a Syrian refugee, she prepares to adopt a child with her boyfriend Steve, all while comforting her terminally ill father, Arthur, who has been admitted to hospital to live out his final days.
2
"Episode 2" Pete Travis Patrick Harbinson 19 June 2017 (2017-06-19) 4.92
3
"Episode 3" Pete Travis Patrick Harbinson 26 June 2017 (2017-06-26) 4.90
4
"Episode 4" Pete Travis Patrick Harbinson 3 July 2017 (2017-07-03) 5.23
5
"Episode 5" Pete Travis Patrick Harbinson 10 July 2017 (2017-07-10) 5.04
6
"Episode 6" Pete Travis Patrick Harbinson 17 July 2017 (2017-07-17) 5.26
References[edit]
Jump up ^ "ITV Media | Fearless". www.itvmedia.co.uk. Retrieved 2017-06-27.
Jump up ^ "Fearless Press Pack" (PDF). ITV Press Centre. 6 June 2017. Retrieved 27 June 2017.
Jump up ^ "Sir Michael Gambon joins the cast of ITV’s Fearless". "ITV Press Centre". Retrieved 2017-06-27.
Jump up ^ "ITV Media | Fearless". www.itvmedia.co.uk. Retrieved 2017-06-27.
Jump up ^ Mangan, Lucy (2017-06-13). "Fearless review – Helen McCrory shines in a fabulously classy thriller". The Guardian. ISSN 0261-3077. Retrieved 2017-06-27.
Jump up ^ "Fearless episode 1 review: Homeland comes to East Anglia". The Telegraph. Retrieved 2017-06-27.
External links[edit]
Fearless on IMDb
Retrieved from "https://en.wikipedia.org/w/index.php?title=Fearless_(TV_series)&oldid=800090148"
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