MarsDial in action
Jan. 17th, 2004 08:48 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mmcirvinHere's (more or less) what I wanted to see, on the Planetary Society's kids page: Bill Nye's MarsDial in action, with some of the pictures in color. (One caveat: I don't know what filters were actually used to take these pictures; sometimes JPL uses a near-infrared filter in place of the visible red one.)
Anyway, this thing has mirrors on it that reflect the sort of tan-beige sky color (they are at about 3 o'clock and 9 o'clock on the circular rim), and bright primary-colored swatches painted on the four corners. Unfortunately the pictures are a little dark, but messing around with the color balance of these pictures in the photo editor of your choice makes it pretty clear that you can't make the sky blue without screwing up all the other colors to a ridiculous extent. (Clarification: The really crucial thing is that the rings in the center are painted a neutral gray color, and they're less red than the mirror images of the sky are. You can pretty easily make the sky images blue by messing with channel curves in an image editor, but then the gray rings get even bluer than that. I am, therefore, pretty confident that the sky on Mars has a tan cast relative to the total incoming light that is illuminating the target.)
Unless, of course, the conspiracy has already gotten to these pictures and messed with them, or secretly swapped the MarsDial with a mis-painted version to fool everybody. For all you know, I'm part of the plot.
Anyway, this thing has mirrors on it that reflect the sort of tan-beige sky color (they are at about 3 o'clock and 9 o'clock on the circular rim), and bright primary-colored swatches painted on the four corners. Unfortunately the pictures are a little dark, but messing around with the color balance of these pictures in the photo editor of your choice makes it pretty clear that you can't make the sky blue without screwing up all the other colors to a ridiculous extent. (Clarification: The really crucial thing is that the rings in the center are painted a neutral gray color, and they're less red than the mirror images of the sky are. You can pretty easily make the sky images blue by messing with channel curves in an image editor, but then the gray rings get even bluer than that. I am, therefore, pretty confident that the sky on Mars has a tan cast relative to the total incoming light that is illuminating the target.)
Unless, of course, the conspiracy has already gotten to these pictures and messed with them, or secretly swapped the MarsDial with a mis-painted version to fool everybody. For all you know, I'm part of the plot.