Pluto

Pluto is the only member of the solar system traditionally classified as a planet not to have been visited by a spacecraft from Earth. As a result, much of the information about this most distant member of the solar system is still incomplete and partially in doubt. It is smaller than any planet in the solar system, with a equatorial radius of 714 miles (1,501 km), about half the size of Mercury and 20 percent the size of Earth. Its mass is about 1.5 x 1022 kg, about 0.0024 that of Earth. Pluto s density is the higher than that of any of the outer planets, about 2.10 g/cm3. 

Great scientific discoveries and important scientific expeditions are usually thought of, planned, and carried out by scientists, but major projects that involve the investment of billions of dollars of public money are often administered and managed by individuals who have little or no background in science and technology itself. The efforts of such individuals are often responsible for the ultimate success (orfailure) of research projects. One of the best examples of this truism is James E. Webb, second administrator of the U.S. National Aeronautics and Space Administration (NASA). 

James Webb was born in Tally Ho, North Carolina, on October 7,1906. He attended the University of North Carolina, from which he received his A.B. in education in 1928. He then joined the U.S. Marine Corps and served as a pilot from 1930 to 1932. After leaving the service, he entered the George Washington University School of Law and earned his L.L.B. in 1936 and was admitted to the District of Columbia Bar. 

Webb s first post-military job was as secretary to Representative Edward W. Pou, of North Carolina s 4th Congressional District, from 1932 to 1934. He then worked for the Washington law firm of O. Max Gardner, former governor of North Carolina, and for the Sperry Gyroscope Company in Brooklyn, New York. When World War II broke out, Webb returned to active duty with the Marine Corps. 

Webb began his tenure as administrator of NASA on February 14,1961, replacing NASA sfirst administrator,T. Keith Glennan. Heserved in this role 

For example, the diameter of Pluto and Eris is nearly the same, about 2400 km, the semi major axis of Pluto is 39.5 AU (high eccentric, orbital radius between 29.66 and 49.3 AU), that of Eris 67.67 AU (high eccentric, orbital radius between 37.77 and 97.56 AU). Ceres has a diameter of 975 x 909 km and the semi major axis is 2.76 AU. Pluto is also regarded as a prototype of Trans Neptunian Objects (TNOs). 

Due to the eccentricity of its orbit, Pluto is closer to the Sun than Neptune for about 20 years. Pluto crossed Neptune s orbit from 1979 to 1999. As Pluto approaches its perihelion, it reaches the maximum distance from the ecliptic 17°. Therefore, a collision with Neptune cannot happen and the closest possible distance between the two planets is about 18 AU. 

Synoptic observations of 134340 Pluto from the Hubble Space Telescope were reported by Storrs, and Eney, 2010 [327]. They reconstructed images over almost two decades to look for surface variations. 

Pluto has a large satellite, Charon, which was discovered in 1978 (Fig. 3.20). A comparison between these two objects shows that Charon might be the result of a large impact on Pluto (like the formation of the Moon). Pluto and Charon are gravitationally locked. They always keep the same hemisphere to each other. The average distance between Pluto and Charon is only 19 570 km. The average density of Charon is 1.65 gcm and its mass is 0.11 that of Pluto. 

Two additional satellites of the Pluto-Charon system were detected in 2005 on images taken with the Hubble Space telescope Nix and Hydra. They are small and not spherical. The diameter of Nix is between 44 and 130 km and the semi-major axis of its orbit is 48 600 km. Hydra is slightly more distant to Pluto, the semi-major axis of its orbit is 65 000 km and its diameter is estimated between 110 and 160 km. 

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Figure 4-7 Output of tfie Optiiiii/,ed Geometry of Propitn-2-ol Dcpictcti as t Pluto Moticl. Pluto is one of several pictorial options provitlcd in PCMOOFI,...

Pluto drawing of cA-2-Butene PCMODEL v8.0. The double bond is not... 

Minimize cw-2-butene. From the View menu, select Pluto. Your screen image should resemhle Fig. 5-6. Go to File and Print your pluto drawing. Repeat with tra s-2-hutene. Include the structure drawings with your report. You can create pluto drawings for any of the stick figures in future computer projects. There are other graphical options. 

Planet pluto) Plutonium was the second transuranium element of the actinide series to be discovered. The isotope 238pu was produced in 1940 by Seaborg, McMillan, Kennedy, and Wahl by deuteron bombardment of uranium in the 60-inch cyclotron at Berkeley, California. Plutonium also exists in trace quantities in naturally occurring uranium ores. It is formed in much the same manner as neptunium, by irradiation of natural uranium with the neutrons which are present. 

Alkanes have the general molecular formula C H2 +2 The srmplest one methane (CH4) rs also the most abundant Large amounts are present rn our atmosphere rn the ground and rn the oceans Methane has been found on Juprter Saturn Uranus Neptune and Pluto and even on Halley s Comet... 

Diacetylene (HC=C—C=CH) has been identified as a component of the hydrocarbon rich atmospheres of Uranus Neptune and Pluto It is also present m the atmospheres of Titan and Triton satellites of Saturn and Neptune respectively... 

Plutonium, Pu G. T. Seaborg, 1940 Bombardment of jU The planet Pluto (next... 

Our solar system consists of the Sun, the planets and their moon satellites, asteroids (small planets), comets, and meteorites. The planets are generally divided into two categories Earth-like (terrestrial) planets—Mercury, Venus, Earth, and Mars and Giant planets—Jupiter, Saturn, Uranus, and Neptune. Little is known about Pluto, the most remote planet from Earth. 

A collision with a Mars-sized object may have resulted in the formation of the Earth s moon. Our moon is by no means the largest satellite in the solar system, but it is unusual in that it and the moon of Pluto are the largest moons relative the mass of the planets they orbit. Geochemical studies of returned lunar samples have shown that close similarities exist between the bulk composition of the moon and the Earth s mantle. In particular, the abimdances of sidero-... 

PLUTO/ANIMOL program developed by R. Hilmer, D. A. Pensak, and J. Christie at Du Pont. 

Figure 1.10. PLUTO views and numbering of spiro compounds (a) 44a (b) 45b.

Name named after Pluto, which recently lost its status as a planet Greek god of the underworld and wealth G. T. Seaborg recognized the analogy between the lanthanoids and actinoids... 

Acknowledgements. The author thanks Dr. S.F. Colmanet for preparing the PLUTO figures. 

Alex K., Yavanian G., McFarlane H., Pluto C., Pehek E. (2005). Modulation of dopamine release by striatal 5-HT2C receptors. Synapse. 55, 242-51. 

Pehec, E. A., McFarlane, H. G., Maguschak, K., Price, B. Pluto, C. P. (2001). M100.907, a selective 5-HT2A antagonist, attenuates dopamine release in the rat medial prefrontal cortex. Brain Res. 888, 51-9. 

The gas giant planets Jupiter, Saturn, Uranus and Neptune. The planet Pluto has a status of its own, and has recently been renamed a dwarf planet. 

In August 2006, the International Astronomical Union redefined the term planet and decided that the former ninth planet in the solar system should be referred to as a dwarf planet with the number 134340. The dwarf planet Pluto and its moon, Charon, are the brightest heavenly bodies in the Kuiper belt (Young, 2000). The ratio of the mass of the planet to that of its moon is 11 1, so the two can almost be considered as a double planet system. They are, however, quite disparate in their composition while Pluto consists of about 75% rocky material and 25% ice, Charon probably contains only water ice with a small amount of rocky material. The ice on Pluto is probably made up mainly of N2 ice with some CH4 ice and traces of NH3 ice. The fact that Pluto and Charon are quite similar in some respects may indicate that they have a common origin. Brown and Calvin (2000), as well as others, were able to obtain separate spectra of the dwarf planet and its moon, although the distance between the two is only about 19,000 kilometres. Crystalline water and ammonia ice were identified on Charon it seems likely that ammonia hydrates are present. 

The search for extrasolar life requires us to find planets outside the solar system. But since stars are only visible as small dots of light, it will be very difficult to find planets in outer space, since these do not emit light. This is true even for the nearest star, Alpha Centauri, which is about 4.3 light years away (roughly 7,000 times the distance from the sun to Pluto). 

When, many, many million years in the future, our sun expands in its Anal phase to become a red giant, the habitable zone of our solar system will shift by 1-2 AU, to the region where Triton, Pluto/Charon and the Kuiper Belt are found. This zone is referred to as the delayed gratification habitable zone . All the heavenly bodies in this zone contain water and organic material, so that chemical and molecular... 

The planet Pluto is estimated at a mean distance of 3,666 million miles from the sun. The planet Mars is estimated at a mean distance of 36 million miles from the sun. How much closer to the sun is Mars than Pluto ... 

The density estimates in Table 7.1 show a distinction between the structures of the planets, with Mercury, Venus, Earth and Mars all having mean densities consistent with a rocky internal structure. The Earth-like nature of their composition, orbital periods and distance from the Sun enable these to be classified as the terrestrial planets. Jupiter, Saturn and Uranus have very low densities and are simple gas giants, perhaps with a very small rocky core. Neptune and Pluto clearly contain more dense materials, perhaps a mixture of gas, rock and ice. 

Fine, B. and Saad-Filho, A. (2004) Marx s Capital, 4th edn, London Pluto Press. 

Grossmann, H. (1992) The Law of Accumulation and Breakdown of the Capitalist System Being also a Theory of Crisis, London Pluto Press, 1929. 

Rosdolsky, R. (1977) The Making of Marx s Capital, London Pluto Press. 

Tarbuck, K.J. (1989) Bukharin s Theory of Equilibrium, London Pluto. 

Plutonium (Pu, [Rn]5/ r 7.v2), name and symbol after the planet Pluto. Discovered (1940, Berkeley) by Glenn T. Seaborg, J.W. Kennedy, A. Wahl. 

Cohen JC, Illingworth P, Schukienk U, eds. The Power of Pills Social, Ethical and Legal Issues in Drug Development, Marketing, and Pricing, Pluto, London, 2006. 

In Greek mythology, Asclepius, the god of medicine, studied medicine under Chiron. He excelled over Chiron, and his medical skills were reputed to be able to bring back the dead. This incurred the wrath of Pluto, the god of the underworld, and the envy of other gods. They complained to Zeus, who also thought that he alone should have the power of life and death. Zeus slew Asclepius with a thunderbolt. However, Asclepius s daughters. Panacea and Hygeia, survived and carried on to tend to the sick. 

J In outer space, frozen water, or ice, has been found on the moon, on planets— particularly Mercury, Mars, Neptune, and Pluto—and in comets and clouds between stars in our galaxy. Recent explorations of Mars indicate that there may be liquid water underground on Mars.This means there could be microorganisms living there ... 

Plutonium - the atomic number is. 94 and the chemical symbol is Pu. The name derives from the planet Pluto, (the Roman god of the underworld). Pluto was selected because it is the next planet in the solar system beyond the planet Neptime and the element plutonium is the next element in the period table beyond neptunium. Plutonium was first synthesized in 1940 by American chemists Glenn T. Seaborg, Edwin M. McMillan, Joseph W. Kennedy and Arthur C. Wahl in the nuclear reaction U( H, 2n) Np = P => Pu. The longest half-life associated with this unstable element is 80 million year Pu. 

Look up an account of the discovery of the planet Pluto. What can be said about the effectiveness of the factors in the models that described the motions of the planets other than Pluto What can be said about the lack of fit of these models to the available astronomical data How was the lack of fit accounted for ... 

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