Juno perijoves 2 and 3, October 19 and December 11, 2016 |
Juno perijoves 2 and 3, October 19 and December 11, 2016 |
Oct 26 2016, 04:44 PM
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#1
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Junior Member Group: Members Posts: 23 Joined: 13-October 13 Member No.: 7013 |
A lot has happened and it seemed like a good time to start a new post. We will be staying in 53 day orbits until the project has a full understanding of the risks that may or may not be associated with reducing the orbit period to 14 days per our previous plan.
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Dec 19 2016, 06:33 PM
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#2
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Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
For those, who like to use the MSSS version of the PJ3 RGB images, but color-corrected, i.e. with much less color striping artifacts, and adjusted color weights.
==== Re Juno and GR: There are even people, who think, that measuring the very subtle Lense-Thirring effect, aka frama dragging, might be feasible during the Juno mission: https://arxiv.org/pdf/1302.6920v5.pdf https://arxiv.org/pdf/0812.1485v3.pdf But the effect I've been thinking about, is much more crude: It's the relative effect of velocity to clocks. And I'm keen enough to use Juno's rotation as a clock. Seen from Jupiter (barycenter), we get velocity changes of about +/- 1e-4 c. For a constant angular velocity, even small to tiny time-dilation sums up to a a small angle, which might be detectable by JunoCam. But as I've calcuated above, we are below 1 pixel per perijove. However displacements well below 1 pixel, in some cases down to less than 1e-2 pixels, are feasible for measurements. We are then in the same order of magnitude as relativistic effects. I've attributed these effects to GR, since we aren't in two inertial systems in a flat spacetime regarding Juno and Earth. But reasonable calculations should be possible with means of Special Relativity. My very first crude presumption without calculations has been, that a velocity of 1e-4 c might result in relativistic effects near 1e-6, but as mentioned above, it's only near 0.5e-8. I was two orders of magnitude off, since the 1e-4 c need to be squared in the calculation for the relativistic effects. The idea came during pondering about the root cause of an angular offset observed during PJ3 image processing. Btw.: Regarding SPICE: Probes close to the Sun may experience considerably stronger relativistic effects. |
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