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Title: Are there rings around Pluto?
Authors: J. J. Rawal, Bijan Nikouravan

Considering effects of tidal plus centrifugal stress acting on icy-rocks and the tensile strength thereof, icy-rocks being in the density range (1-2.4) g cm-3 which had come into existence as collisional ejecta (debris) in the vicinity of Pluto at the time when Pluto-Charon system came into being as a result of a giant impact of a Kuiper Belt Object on the primordial Pluto, it is shown, here, that these rocks going around Pluto in its vicinity are under slow disruption generating a stable ring structure consisting of icy-rocks of diameters in the range (20-90) km, together with fine dust and particles disrupted off the rocks, and spread all over the regions in their respective Roche Zones, various Roche radii being in ~1/2 three-body mean motion resonance. Calculations of gravitational spheres of influence of Pluto which turns out to be 4.2 x 106 km for prograde orbits and 8.5 x 106 km for retrograde orbits together with the existence of Kuiper Belt in the vicinity of Pluto assure that there may exist a few rocks (satellites)/dust rings/sheets so far undiscovered moving in prograde orbits around the planet and few others which are distant ones and move around Pluto in the region between 4.2x106 km and 8.5x106 km in retrograde orbits.

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Pluto was demoted to a Dwarf Planet by the International Astronomical Union (IAU) on the 24th August, 2006.

After years of wrangling and a week of bitter debate, astronomers voted on a sweeping reclassification of the solar system. In what many of them described as a triumph of science over sentiment, Pluto was demoted to the status of a "dwarf planet."
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Dwarf Planet (134340) Pluto is at Opposition (31.038 AU) on the 28th June, 2011.



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Dwarf Planet (134340) Pluto makes its closest approach to the Earth (31.062 AU) on the 26th June, 2011.



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James Walter Christy (born 1938) is an American astronomer.
Working at the United States Naval Observatory, on June 22, 1978 he discovered that Pluto had a moon, which he named Charon shortly afterwards. The name remained unofficial until its adoption by the IAU in 1986.

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The name Pluto was proposed by Venetia Burney (19182009), an eleven-year-old schoolgirl in Oxford, England.
The object was officially named on March 24, 1930. Each member of the Lowell Observatory was allowed to vote on a short-list of three: Minerva (which was already the name for an asteroid), Cronus (which had lost reputation through being proposed by the unpopular astronomer Thomas Jefferson Jackson See), and Pluto. Pluto received every vote. The name was announced on May 1, 1930. Upon the announcement, Madan gave Venetia five pounds as a reward.
It has been noted that the first two letters of Pluto are the initials of Percival Lowell, and Pluto's astronomical symbol  is a monogram constructed from the letters 'PL'

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Title: Discovery of carbon monoxide in the upper atmosphere of Pluto
Authors: J.S. Greaves, Ch. Helling, P. Friberg

Pluto's icy surface has changed colour and its atmosphere has swelled since its last closest approach to the Sun in 1989. The thin atmosphere is produced by evaporating ices, and so can also change rapidly, and in particular carbon monoxide should be present as an active thermostat. Here we report the discovery of gaseous CO via the 1.3mm wavelength J=2-1 rotational transition, and find that the line-centre signal is more than twice as bright as a tentative result obtained by Bockelee-Morvan et al. in 2000. Greater surface-ice evaporation over the last decade could explain this, or increased pressure could have caused the atmosphere to expand. The gas must be cold, with a narrow line-width consistent with temperatures around 50 K, as predicted for the very high atmosphere, and the line brightness implies that CO molecules extend up to approximately 3 Pluto radii above the surface. The upper atmosphere must have changed markedly over only a decade since the prior search, and more alterations could occur by the arrival of the New Horizons mission in 2015.

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Clyde Tombaugh discovers the dwarf planet Pluto. (1930)
The discovery was made on Tuesday, February 18, 1930, using images taken the previous month.

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Frigid Pluto, home to some of our solar system's chilliest real estate, may well harbour an ocean beneath its miles-thick ice shell, new research suggests.
Despite its extreme cold, the dwarf planet still appears to be warm enough to "easily" have a subsurface ocean, according to a new model of the rate at which radioactive heat might still warm Pluto's core.
And that ocean wouldn't be a mere puddle, noted planetary scientist Guillaume Robuchon of the University of California, Santa Cruz.
Rather, the ocean could be 100 to 170 kilometres thick beneath a 200-kilometer layer of ice, Robuchon said at an annual meeting of the American Geophysical Union in San Francisco earlier this week.

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Pluto is at Opposition (distance to Earth: 30.842 AU, magnitude: 14.0)

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