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Politics : CONSPIRACY THEORIES -- Ignore unavailable to you. Want to Upgrade?

To: sea_urchin who wrote (120)	1/25/2005 4:10:21 AM
From: GUSTAVE JAEGER	Respond to of 418

Re: So don't worry about the shadow -- even though the picture was most likely taken in the Western Sahara! Did you check the MOC Image Gallery? Click on the link and you'll see that they (MOC operators) claim to have shot over 175,000 pictures of Mars!!!! I tell you: those pics from Titan are actually inedited Martian pics that were uploaded to Cassini by NASA --and subsequently sent back as "Titan pics".... As far as I'm concerned, I wasn't suspicious so much about the "shadow/ghost" as about the narrowness of the picture --the way it was trimmed edgewise... My point being that, given a wide enough picture, it's possible to calculate the radius of the planet where the picture was shot....() Gus () Limits of Precision A spherical object appears as an elliptical, parabolic or hyperbolic outline on a movie frame. In theory it is straightforward to measure five different points on that outline, calculate the coefficients of the conic section, and infer the field of view and the 3D position of the sphere in units of its radius. In practice there are several possible sources of difficulty, imprecision and ambiguity in the measurements or in the inference. Firstly, the image does not contain spatial information finer than a pixel. Therefore it is impossible to pick sample points more precisely than within one pixel inside or outside the ideal horizon curve. Uncertainties will propagate into the inferred conic coefficients and thence to the derived parameters of the sphere. Secondly, the horizon may not be completely measurable. In the best possible scenario, we can pick measurement points that are roughly evenly spaced on all sides of an ellipse. Both the semimajor and semiminor axes are well constrained from both the left and right (top and bottom) sides. However if one side of the globe falls off the edge of the image, or is invisible because of obstruction or shadow, then that side is poorly constrained. The inferred ellipse has a lot of scope for variation in the direction of the unmeasured side, for very tiny deviations on the choices of reference points in the measurable sides. In the worst possible cases, the majority of the horizon is off the edge of the screen and we can only measure a tiny angular arc, which appears almost straight. The axes of the curve become practically unmeasurable, and even the type of conic section may be indeterminate. Attempts to read the local radius of curvature are misleading and provide neither upper nor lower limits, because the field of view is unknown and the aspect ratio of the ellipse/hyperbola is unknowable. As the camera tilts away from a sphere, the area and eccentricity of the onscreen ellipse both increase. An image that is tilted far offscreen is thus magnified and distorted compared to the appearance it would have when centred in the field. When only a small, flat arc is visible and the field of view is unknown then the distortion and magnificiation are inestimable. Circular approximations are only useful when the disk is entirely within the field of view and close to the centre of frame. If the disk is measurably indistinguishable from a circle then we automatically know that the sphere is close to the line of sight and the field of view is narrow.

To: sea_urchin who wrote (120)	1/25/2005 4:30:40 AM
From: GUSTAVE JAEGER	Respond to of 418

Footnote: Limits of Precision is excerpted from: theforce.net

To: sea_urchin who wrote (120)	1/25/2005 6:24:20 AM
From: GUSTAVE JAEGER	Read Replies (1) \| Respond to of 418

Re: The whole whizbang Huygens-Cassini "Star-Trek" to Saturn's satellite was a HOAX!!! Another funny yet suspicious thing about Cassini-Huygens is that the mission relied on much older technologies than its ill-fated "Mars Express" sequel... Indeed, the latter was carried out in the early 2000s and accordingly used the latest technologies (in electronics, telecom, materials,...) yet FAILED. Whereas Huygens-Cassini is an older story that started back in 1997 --hence using technologies of the early 1990s... The landing of a probe on Mars should be a cakewalk compared to the landing of a probe on Titan 1.2 BILLION kilometers away! nssdc.gsfc.nasa.gov Mars Express set off on 2 June 2003 At this time of year the positions of the two planets made for the shortest possible route, a condition that occurs once every 26 months. The intrepid spacecraft began its six-month journey from the Baikonur launch site in Kazakhstan on board a Russian Soyuz/Fregat launcher. Having escaped the Earth's pull, Mars Express was sent on course for the Red Planet, cruising at a velocity of 10 800 kilometres and hour, relative to Earth. Six days before arrival on 25 December 2003, Mars Express ejected the Beagle 2 lander which was to have made its own way to the correct landing site on the surface. The orbiter successfully entered Martian orbit on 25 December. First it manoeuvred into a highly elliptical capture orbit from which it moved into its operational near polar orbit later in January 2004. esa.int The journey Cassini-Huygens was launched on a Titan IV-B/Centaur launch vehicle on 15 October 1997. It is a massive spacecraft - no existing launch vehicle could have sent the 5600 kilogram craft directly to Saturn, so a technique called 'gravity assist' (or 'fly-bys') was used. [...] esa.int