Wednesday, June 17, 2015

2015: A SPACE ODYSSEY . Part 7.

A long time ago I was pondering if I will ever live to see the Planet (1)>> Pluto , Thankfully NASA's New Horizons spacecraft is still 24 million miles and more than a month away from the dwarf planet Pluto, but the probe's pictures are already revealing a world that's more complicated than previously thought.I have been waiting for a probe to reach Pluto since Voyager 1. I was very disappointed that neither Voyagers visited the "planet". I would prefer the probe go into orbit but that isn't a possibility at this point. Let's hope there's no glitches or problems during New Horizons brief fling with Pluto and her sisters. Pluto is going to show all of us that it might not be the planet we need right now, but it is the planet we deserve.In fact, since Pluto is quite large enough for the force of its self-gravity to overcome the strength of its icy material, there is no question that it will be very much round, more round than Ceres. (Pluto has the same density as Ceres, so has similar ice/rock composition, but Pluto has more than 14 times Ceres' mass, so its gravity is significantly stronger.) Roundness is one of the very few things that we can confidently predict about Pluto before New Horizons' flyby, because basic physics does a remarkably good job of predicting bulk physical properties of space objects.Pluto was once considered the oddest of the solar system's nine planets, but over the past decade, more objects like Pluto have been discovered on the solar system's icy edge, more than 3 billion miles (5 billion kilometers) from the sun. Now Pluto is considered one of the largest objects in a category known as dwarf planets.  The surface of Pluto is coming into focus as NASA’s New Horizons spacecraft gets closer to its flyby next month.A series of new pics snapped by the probe’s on board Long Range Reconnaissance Imager (LORRI) at the end of May and start of June show that Pluto’s has a complex terrain, with very bright and very dark areas as well as grades in between.Telescopic Long Range Reconnaissance Imager (LORRI) on May 29-June 2 captured images showing Pluto to be a multifaceted world with areas of intermediate brightness in between and ultra bright and ultra dark terrain. The captured images are the best views ever obtained of Pluto’s planetary system.A technique called deconvolution was used by New Horizons scientists to sharpen the raw, unprocessed pictures the spacecraft transmits back to Earth.  The latest image’s contrast were magnified to reveal additional details. Deconvolution sporadically produce artifacts, so the team will review newer images taken at close range to conclude whether the tantalizing detail seen in the latest released images still persist. Pluto’s non-spherical form in these images is not real; it resulted from the combined image-processing procedure and Pluto’s large disparities in surface brightness.
Pluto's Moons.

Pluto's moons at long Range . Via
Hubble Telescope.
The five moons of Pluto form a sort of miniature planetary system — one that is unique in the solar system.The largest, Charon, 750 miles wide, was discovered in 1978, and it is so large, about one-ninth the mass of Pluto, that the center of mass of the two lies outside Pluto. That has led some planetary scientists to regard Pluto and Charon as a double planet. The observations led to the discovery of the moons Nix and Hydra in 2005,Kerberos in 2011, and Styx in 2012. In contrast to (2)>> Charon, which is about half as wide as Pluto itself, these four smaller moons are thought to be no wider than 36 miles (60 kilometers) — and Styx's diameter could be less than 5 miles (8 kilometers).In an article published Wednesday in the journal Nature, Mark R. Showalter of the SETI Institute in Mountain View, Calif., and Douglas P. Hamilton of the University of Maryland calculated more precisely the orbits of the four smaller moons and turned up some surprises.For one, Nix, jostled by the competing gravitational pulls of Pluto and Charon, appears to be rotating chaotically.The moons of Pluto keep coming back to nearly the same configuration time and time again, the researchers found. Charon completes three orbits, for instance, in roughly the same time Styx loops around once. Since it’s unlikely that all five moons became synced by chance, they likely have a common origin, More moons could be lurking around Pluto. Any additional moons are likely to be tiny — small enough to evade detection by the Hubble Space Telescope, which spotted the four smallest. So, it’ll be up to New Horizons to find them while it’s in Pluto’s neighborhood.

Ceres and the "Strange Lights".
The Best Dawn space probe
image of  Ceres . (see
note # 3 )
The Dwarf Planet (3)>> Ceres is leaving NASA pondering on the best explanation of the "lights" on the surface  . Clearly, most of us are working under the assumption that these bright lights are obvious alien civilization(s), but scientists working on the Dawn mission contend that the lights are likely ice or salt deposits. As Dawn gets closer to Ceres, scientists are hoping that more detailed images can provide better information about the planet – they suspect that billions of years ago, the dwarf planet was warmer and may have been able to support life. When Dawn reaches its closest orbit around Ceres, it will be able to transmit images 36 times more detailed than it currently has, so we'll finally be able to see what, if anything, those lights. Now here's a spot of a different color: The latest picture released by the science team for NASA's Dawn mission shows a bright patch on the dwarf planet Ceres that's distinct from the eerie "alien headlights" seen in other imagery.The best-known collection of bright spots on Ceres is known as "Spot 5," and the best guess is that those spots are made of ice deposits — although scientists haven't completely ruled out the possibility that they're made of salt or some other light-colored material. Most models of Ceres depict a rocky crust,  mantle of ice and a rocky inner core.  This makes us wonder if the bright material unearthed might be ice. If so, it would gradually vaporize on the virtually air-free dwarf planet. Dawn will spend through early 2016 at Ceres during its primary mission and then remain in orbit there perpetually. We should be able to cipher the composition of the white material during that time with the spacecraft’s Gamma Ray and Neutron Detector andVisible and Infrared Mapping Spectrometer, but a lengthy stay might allow us to see changes in the extent of any ice exposures as they gradually vaporize away. (4)>>Either way, the sights are spectacular. And they have already gotten even better.

(1)>> When the New Horizons spacecraft left the earth in 2006, Pluto was still considered a planet.  But a re-examination of the definition of "planet" ended up in the demotion of Pluto to the classification of a "dwarf planet."  This was necessary, because observers have discovered a half-dozen icy bodies beyond Neptune as big as or bigger than Pluto.  Rather than expanding the number of planets to accommodate what are surely many thousands of bodies like Pluto, scientists opted for clarity and simplicity in classification.It hardly matters.  Pluto is a strange, weird place, and the pictures and data that we've already been able to get from New Horizons promise to upend our theories of Pluto and its bizarre moons.(2)>> Charon .What about inside Charon’s orbit? No one thinks that’s exceptionally likely, which is great news for the spacecraft’s safety because it’s scheduled to fly through that regionInformation gathered by the Hubble space telescope tells us Nix and Hydra, two moons of the dwarf planet, are embedded in a constantly shifting gravitational field. As a result, Nix and Hydra wobble and tumble unpredictably. (3)>> These latest images come from June 6, when Dawn was orbiting 2,700 miles above the surface of Ceres. It's now clear that this crater (about 55 miles across) is home to a bunch of highly respective white patches, which seem to also exist in less abundance on other parts of the planet. But what are they? These images, while the best we've seen, aren't enough to solve the mystery.(4)>> We have discussed them here and there in recent months, and their luminous power continues to dazzle us. What appeared initially as one fuzzy spot proved to be two smaller spots and now many even smaller regions as the focus has become sharper. Why the ground there reflects so much sunlight remains elusive. Dawn’s finer examinations with its suite of sophisticated instruments in the second, third and then final mapping orbits will provide scientists with data they need to unravel this marvelous mystery. For now, the enigmatic lights present an irresistible cosmic invitation to go closer and to scrutinize this strange and wonderful world, and we are eager to accept. After all, we explore to learn, to know the unknown, and the uniquely powerful scientific method will reveal the nature of the bright areas and what they can tell us about the composition and geology of this complex dwarf planet.

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