Question regarding Huygens surface video |
Question regarding Huygens surface video |
Dec 9 2016, 08:29 AM
Post
#1
|
|
Junior Member Group: Members Posts: 43 Joined: 14-December 12 Member No.: 6784 |
Recently I found a short animation of several of the images taken of the Titan surface by Huygens after it landed:
Link to animation. I see that several objects appear to move in and out of frame, which I have read is attributed to fluffy aerosols kicked up from the surface settling down again. My question is, what is the explanation for the object which appears to move horizontally from left to right? If it is in fact the same object in all 3 frames from frame 11-13, it appears at (x,y) pixel coordinates (74,290), (119,291), and (212,297). Is it something on the lens, drifting to the side perhaps? Because I do not know how this sequence of images has been combined, and whether or not they are chronological or in reverse order, or whether there are missing intermediate frames, I cannot estimate the time that passes during the movement of this small blob. Finally, is there a table somewhere with timestamps of all the Huygens triplets? Regards, Nick |
|
|
Dec 12 2016, 05:30 PM
Post
#2
|
|
Senior Member Group: Members Posts: 2530 Joined: 20-April 05 Member No.: 321 |
The jpeginess, as others noted, is far too great to take the details as indications of real objects.
Recently, I used my telescope camera with my microscope, and – although I should have expected this – I was struck by the lack of temporal variation that the telescope role had gotten me accustomed to. When you look through the Earth's entire atmosphere, things jiggle at all times. When you look through a centimeter of air, things don't. The Huygens view is something in between. It's interesting that there's any variation here. That is, if we make sure that this is also true in the best possible version of this kind of display. One really interesting piece of information we have is that the foreground is far closer than the background. If there are pure artifacts at work, then they ought to appear similar in kind in the foreground and the background. If there is something real there, seen in multiple instances, then we should see the scale vary based on distance. Another thing we should expect to see in something physically real is a linear trend over 3+ frames. If things pop around randomly from frame to frame, there's no such evidence. If something appears to move, we can apply checks of significance vs. the probability of three "pops" of noise happening to align. This is similar to the math done in examining candidate planets in the Kepler data. The potential is there to make a case for the reality of things in a Huygens video. We know that Huygens apparently altered its environment by boiling off some surface CH4, increasing its abundance in the air. We also know that Titan likely experiences a "snow" / ash of compounds that form in its upper atmosphere. Yet another possible phenomenon would be motions of light and shadow caused by clouds overhead (though this may be at odds with the observation that clouds are typically quite few and far between). I'd love to see the possibility checked out thoroughly, but a display with highly visible squares all over the place doesn't seem like the data to start with. |
|
|
Dec 13 2016, 04:04 PM
Post
#3
|
|
Junior Member Group: Members Posts: 64 Joined: 17-December 12 From: Portugal Member No.: 6792 |
The image sequence (in chronological order) shows the lander's light dimming as time passes and the battery runs out.
At least I remember reading something regarding the lamp Vs ambient light levels and that's the only noticeable change. Here's an official release with all the data: https://www.youtube.com/watch?v=sZC4u0clEc0 Once tried to use that difference in illumination to get some color, but that JPG compression is just too high. An interesting processing would be to properly de-block the images (also for Pathfinder or Galileo). -------------------- www.astrosurf.com/nunes
|
|
|
Lo-Fi Version | Time is now: 25th June 2024 - 03:47 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |