Mars Opposition of 2020-2021
December 29. 2020.
I got this image of Mars under poor seeing and average transparency with the ASI183MC at the f/14 focus of the 7.25” Schupmann. Only 10.63 arc seconds in
December 27, 2020. Although Mars is getting smaller, only 11 arc seconds now, there are still discernible details on the planet. Got the attached image in below average seeing with the ASI183MC at the f/14 focus of the 7.25” Schupmann.
December 11, 2020. It was a little hazy here tonight, with about average seeing. Got ten 90 second videos of Mars at the f/14 focus of the Schupmann using the ASI183MC. Processed as usual to give the animated gif and labeled derotated stack of all the images. It is near the end of southern hemisphere summer and pretty much all the CO2 ice has sublimed off the South polar cap, leaving only the permanent water ice remnant.
November 29, 2020. Got a set of 13 one-shot color videos tonight in below average seeing. Did not have the stamina for a set of NIR, but it might have been useful since there was considerable amount of dust obscuration over Mare Erythraeum, Aurorae Sinus and places east. See derotated stack below of the images from aligning and stacking the best 5% of the frames from tonight. Some pics I have seen from parts of the world where Syrtis Major and Hellas are visible show Hellas as a very high albedo feature, with a yellowis color indicating dust settling out at low altitude. Thus far this opposition, Hellas has been of relatively low albedo and blending in with the surrounding region, looking more like the wintertime Hellas with white clouds over it or snow on the surface.
November 28, 2020. I observed Mars with both visible and NIR light tonight. Seeing was poor, probably no better than 2/10. Transparency was good. I had two sessions, one around 5 PM EST, the other around 7 PM. In the first session I was able to get three 90 second videos in visible light with the ASI183MC at the f/14 focus of the 7.25" Schupmann and four 90 second videos in NIR with the 850 nm longpass filter on the ASI290MM. A 1.5x Barlow was used, but spacing was not the standard spacing. Probably working closer to 2x. The images from this session are the first two below. At the later session I was able to get four 90 sec videos in NIR, but when I switched back to the color camera, seeing had deteriorated so badly that focusing was impossible. The NIR image from the later session is the third image below. I was expecting to see some difference between the visible and NIR images consistent with dust reported over Mare Erythraeum. I don't see it. Perhaps it has settled out.
November 26 (EST), 2020. After a nice post Thanksgiving Dinner nap, Chewie and I went out to the observatory for a relatively comfortable evening of imaging. It was actually quite warm today, and had not cooled off much by the time we were out around 7:45 PM. I took seven 90 second videos of Mars and then eight videos of the Moon, enough for a mosaic and a couple of closeups. I used the ASI183MC at the f/14 focus of the Schupmann. Seeing was a little below average for the Mars imaging, started off about the same for the moon, but deteriorated near the end of the series for the mosaic. I processed all the videos in Autostakkert3, using the deconvolutive sharpening provided by the program. Seems to work better than the wavelets in Registax and is much less prone to overprocessing artifacts. The 7 images of Mars were derotated and stacked and then lightly sharpened in Registax6. Labeled result is shown below. No sign of significant dust storm activity. The results from the moon imaging are on the "Lunar Current" page.
November 25, 2020. The sky was a bit murky and seeing was unsteady when I took a set of four 90 second videos of Mars with the ASI183MC at the f/14 focus of the 7.5" Schupmann Medial telescope, and two 90 second videos with the ASI290MM with 850nm longpass filter. The videos were processed in AS!3, keeping the best 25% of the frames. After histogram adjusting to a black point of 20 and a white point of 170 the images were derotated and stacked and slightly sharpened in Registax6 to give the result shown below. Little if any trace of the dust storm is seen on the preceding limb over Solis Lacus. Perhaps the storm will not go global.
November 19, 2020, Next day.
Seeing quite poor today, transparency somewhat murky. Got six 90 second videos and processed as usual. Not very well resolved image. Some suggestion of dust on the eastern (left) limb of the planet.
November 19, 2020. Transparency was fair and the seeing a little below average tonight when I got ten 90 second videos with the ASI183MC at the f/14 focus of the 7.25" Schupmann Medial Telescope. The videos were processed in Autostakkert3, stacking the best 5% of the 34782 frames in each video with deconvolution selected. The resulting TIFF files were enlarged 4x, histogram adjusted to a black point of 20 and a white point of 170, then derotated and stacked in WinJupos to give the image shown below. They were also combined with GIMP to give the animation shown at the left.
There is no sign of the dust storm activity that is present on the other side of the planet. This activity evidently started from the orange-brown streaks out of Cydonia that I imaged on November 5 and November 7.
November 15, 2020. Seeing was not projected to be very good tonight, agreeing with the 100 mph Jet Stream forecast. I went out anyway, beats clouds. I took eleven 90 second videos with the ASI183MC at the f/14 focus of the Schupmann. They were aligned and stacked with deconvolution in Autostakkert3, keeping the best 25% in the stack. The sharpened TIFF files were then resized 4x and the histogram adjusted to a black point of 20 and a white point of 170 and then combined with GIMP to give the animated GIF at the right. They were also derotated and stacked in WinJUPOS and, after some sharpening with wavelets in Registax6 (and the color balance and histogram adjusted) to give the result shown below.
November 10/11, 2020. Clear tonight, seeing predicted to be average. Set up with ASI183MC at the f/14 focus of the 7.25" Schupmann and began taking one minute videos at 23:55 UT (6:55 pm Nov.10 EST). Seeing was average with moments of greater clarity. I continued taking one minute videos up until 00:17 UT (7:17 pm EST). The videos were processed with Autostakkert!3 with deconvolution turned on and the resulting TIFF files imported into Photoshop, scaled up 4x and histogram adjusted to a black point of 20 and a white point of 170. All were combined in GIMP to give the animation at the left and then derotated and stacked with WinJUPOS to give the image shown below.
In a later session starting at around 8:49 PM, I was only able to capture 7 videos when a brisk breeze started up, making it difficult to keep the image centered in the ROI. The image was jiggling about +/- 20 arc seconds or so. These 7 videos were aligned and stacked in Autostakkert3 keeping only the best 10% of the frames. The resulting TIFF files were enlarged 4x, histogram adjusted as in the first session and derotated and stacked to give the result at the bottom of this section.
November 8, 2020. CSC and the Jet Stream forecast both predicted above average seeing tonight. Alas, it was not to be. I started observing early, a bit before 8 pm EST, and got 9 one minute videos under really bad seeing conditions. Besides jiggling about furiously, the image sometimes drifted out of the ROI, requiring constant attention to keep the image centered. I came back again a bit after 9 pm and got another set of 9 videos and again at 10:20 and 11:54. Seeing was considerably better for the last three sessions, but not more than 5/10 at best, and often considerably worse. The videos from all four sessions were aligned and stacked in AS!3, keeping the best 25% of the frames and using deconvolution in AS!3 for sharpening. All 36 of the resulting TIFF files were loaded into Photoshop, scaled up 4x and histogram adjusted and saved out as high quality JPEG files. All of these were combined into the animated GIF shown above and then derotated and stacked in four sets using WinJUPOS. The resulting stacks were lightly sharpened and histogram adjusted in Registax6 to give the images shown below. No evidence of dust activity tonight, but the "canal" Deuteronilus shows up nicely in the image from 03:15 UT exactly where the orange-brown streak of dust activity had appeared on the images of November 5 and 7. My suspicion is that the abrupt change in elevation at the location of Deuteronilus (~4000 meters up from the abyssal plain in Cydonia to the cratered plains of Arabia, Eden and Moab) constitutes a barrier to airflow that guides the dust storm along the canal to the South west across Niliacus Lacus and Chryse.
November 7, 2020. Sky was quite clear when I went out to observe Mars tonight. Set up the ASI183MC camera at the f/14 focus of the 7.25" Schupmann and took a set of 20 one minute videos using an ROI of 168x152 and a shutter speed of 1.5 ms. This gave me a frame rate of 386fps and 23188 frames per video. Processed in AS!3 with deconvolutive sharpening. Resulting TIFF files were then scaled up 4x and the histogram adjusted to a black point of 20 and a white point of 170 and saved back out as high quality JPEGs. These were combined using GIMP to give the animated GIF shown at the left and also derotated and stacked in WinJUPOS to give the image shown below.
November 6, 2020. I opened up the observatory around 01:30 UT and began imaging with the ASI183MC at the f/14 focus of the 7.25" Schupmann. The goal tonight was to see if any evidence for the "dust storm" that may have been happening the previous night was still present. A set of 16 one minute videos were taken and processed in AS!3 stacking 24% of the best frames of the 21913 in each video using the deconvolutive sharpening provided by the program. The resulting 16 TIFF files were derotated and stacked in WinJUPOS and lightly sharpened and histogram adjusted in Registax6 to give the image shown below. They were also combined using GIMP to give the animated GIF shown at the right.
Looking carefully in the region from north of Cydonia to Niliacus Lacus, I find no trace of the orange-brown streak seen in the image of November 5. If the streak was a dust storm, it has subsided by now.
November 5, 2020. I obtained a total of 21 images from my observations between 02:23 and 02:43 UT last night. There is an interesting orange/brown streak extending from south of Cydonia, across Niliacus Lacus and into Cydonia. See derotated and stacked image below.
I first thought this might be an artifact of the peculiar nature of a Schupmann. Sometimes spiders invade the tailpiece and spin webs in the converging beam from the objective in front of the field mirror. Since there is a large amount of longitudinal chromatic aberration in the image formed by the simple lens objective, color artifacts can be introduced by a web passing through the plane of focus of a particular wavelength of light. The artifact will be minus the color of the wavelength focused where the web is. Particularly troublesome is a web right on the field mirror surface where green light is focused. This produces a magenta (minus green) artifact. However, when I combined all 21 images into the animated GIF shown above I could see that the potential artifact actually rotates with the planet. Spider web shadows do not do that, so, I believe that it is a real feature that appeared since my observations on November 4 which do not show it. Dust storm activity?
I plan to do a dusting and cleaning of the tailpiece of the Schupmann anyway, just to make sure there are no webs or wrapped up and hanging fly carcasses in there to give me troubles. Note also the white clouds over the western (following) limb.
November 4, 2020. Transparency was above average and seeing below average. I took a set of 17 one minute videos between 02:04 and 02:21 UT at 1 ms shutter and two more one minute videos at 10 ms and 50 ms, greatly overexposing Mars in hopes of spotting Phobos. Didn’t work. Could not see the tiny moon. I believe seeing was not good enough and it was spread out into a seeing blur and too faint to record. The 17 properly exposed videos were processed in Autostakkert!3 and the best 10% of 24365 frames aligned, stacked and sharpened by deconvolution. The resulting TIFF files were then derotated and stacked in WinJUPOS and finally sharpened up slightly with Registax6 to give the result shown below.
November 1, 2020. Chewie (my night assistant) and I had a good but cold session last night in the observatory. We were both bundled up in our matching
red flannel quilted jackets and seeing was decent. I took a set of eleven 60 second videos of Mars and processed them in AS!3 with deconvolutive sharpening keeping only the best 10% of the
23,645 frames for stacking. 10 of the images (one was messed up by edge of frame collision) were derotated and stacked and the result lightly sharpened in Registax6. The labeled image
is shown below. The deconvoluted TIFF files from AS!3 were also assembled into an animated GIFF shown at the right.
October 31, 2020. Last night the transparency and seeing were average and it was quite cold. Glad I picked the last of my Habañeros yesterday, they would have frozen last night!
I took a set of 15 one minute videos of Mars with the ASI183MC at the f/14 focus of the 7.25” Schupmann. These videos were then aligned and stacked with deconvolution in Autostakkert!3 and the animated GIF at the left was prepared from the resulting images. The images were then derotated to a common central meridian and stacked again in WinJUPOS and finally, lightly sharpened with wavelets in Registax6. The result is shown below. Note Solis Lacus on the central meridian. Valis Marineris is prominent. The South Polar Cap remnant is quite small.
October 22, 2020: For my first observations running the telescope on the Utility’s electricity instead of my 4 kw generator I had a pretty productive experience. I had two sessions, one after 10 PM and the other after 1 AM, both with the ASI183MC at the f/14 focus of the Schupmann. In the first session, the transparency was good, but the seeing only average, in the second, seeing was very good, but the transparency was poor and variable. Got some good videos both sessions though. The first two attachments are from the early session. Solis Lacus and Olympus Mons are prominent. The second two attachments are from the later session. Mare Sirenum and Mare Cimmerium are prominent, and two Martian craters are visible, Newton crater, a site of possible hydrological activity, is the dark spot between Mare Sirenum and Phaetontis, and Gail Crater, where Curiosity is exploring, is the blob at the northern tip of Sinus Gomer.
In the first session, the transparency was good, but the seeing was only average. I obtained 17 one minute videos using a shutter speed of 1.0 ms and a gain of
348 and I achieved a frame rate of 401fps and captured 23113 frames in each video. I used Autostakkert!3 to align and stack (with deconvolution) the best 10% of the frames from each
video. All the images were combined in GIMP to produce the animated GIF at the right. WinJUPOS was then used to derotate and stack all the images to provide a single image with
another 4x gain in s/n. The labeled result of this operation is shown below. Solis Lacus, Mare Sirenum, and Olympus Mons are prominent in this image, as is the residual South Polar
In my second session after 1 AM I found that the seeing was much better than the earlier session, but the transparency was worse and variable. Using the autohistogram tool in Firecapture, I was able to get eight usable videos though. They were aligned and stacked in Autostakkert!3 with deconvolution, and the resulting images combined using GIMP to give the animation shown at the left. Then all the images were derotated and stacked in WinJUPOS to give the image shown below. The prominent dark band going all across the image is Mare Sirenum and Mare Cimmerium. Olympus Mons is the light spot at about 8 o'clock. Two Martian craters are visible. Newton crater is located between Mare Sirenum and Phaethontis and is the site of possible hydrological activity, and Gale crater, located at the northern tip of Sinus Gomer is where Curiosity rover is exploring.
October 19, 2020. Transparency was good (8/10) and seeing average (5/10) when I took a set of 16 one minute videos of Mars with the ASI183MC camera at the f/14 focus of the 7.25" Schupmann. I used a shutter of 1.1 ms and a gain of 352 and achieved a frame rate of 386 fps using an ROI of 195x152 pixels. Each video contained 23190 frames. Autostakkert!3 with deconvolution enabled was used to align and stack the best 5% and 10% of the frames, putting the results in separate folders. All of the sharpened stacks in the 5% folder were derotated with WinJUPOS, stacked, and slightly sharpened and color balanced in Registax 6 to give the image shown below. All the stacks in the 10% folder were combined into an animated GIF in GIMP. The result is shown at the left.
October 18, 2020. I had a not very great session with Mars last night. Transparency was high so I did get very high frame rates, but seeing was so bad that sometimes Mars inflated like a balloon and expanded out of the ROI. Attached is derotated and stacked image from 7 one minute videos. I took 9 videos in all, but seeing was so bad during one of the captures that I did not derotate the image from that video, and in another one, Mars ran into the edge of the ROI a couple of times and left a dent on the top. So, only 2.6x gain in s/n from the derotation, however, I did stack 1182 frames for each image, so that is another 34x, overall, 91x improvement in s/n. For seeing as bad as it was, the result is quite pleasing. Final annotated result below. Note Olympus Mons on lower left limb and Elysium Mons on lower right limb. The South Polar Cap is almost gone, and cloud cover from the North Polar Hood is peeking over the northern horizon.
October 15, 2020. Although transparency was excellent tonight, seeing was poor. I took a set of 10 one minute videos of Mars with the ASI183MC at the f/14 focus of the 7.25" Schupmann Medial telescope. I was able to use a short exposure of only 1 ms at the modest gain of 340 and obtained 352 fps. The videos were processed with Autostakkert3 with deconvolution, keeping the best 5% of the 21145 frames. All ten images were derotated at stacked in WinJUPOS and the stack sharpened, color balanced and histogram adjusted in Photoshop Essentials to give the annotated result at the right. Although seeing was poor, major albedo features show up nicely, including Elysium near center in the far North, Mare Cimmerium, including Gomer where Gale crater is located, and Mare Sirenum. Mare Chronium as well as the lighter areas Phaethontis, Electris, Eridania and Ausonia appear in the South. Syrtis Minor is near the west limb and both Syrtis Major and Hellas are just over the west limb. A tiny South Polar Cap is still present.
October 10, 2020. Seeing and transparency both poor tonight. Took 9 one minute videos of Mars with the ASI183MC and the Schupmann. Results at left. With this seeing, I estimate that to get 200 good frames to stack I would have had to take about 3 million of them, about 2.25 hours worth of video.
See: Cyril Cavadore, Seeing and Turbulence,
October 9. 2020. Nice and clear tonight, but seeing is not steady. Moments of clarity, but wild distortion of the image. I set up the 7.25", f/14 Schupmann with the ASI183MC one-shot color CMOS video camera on Mars and took 20 one minute videos using a shutter speed of 1.0 ms at 384 gain. Got 374 fps and 22536 frames per video. These were processed with Autostakkert!3 with folders for 25, 10, 5 and 2% stacking of the best frames. WinJUPOS was used to derotate and stack the 20 deconvoluted TIFF images from the 5% folder. Registax6 was used for slight sharpening and color balance. The result is shown below. The images from the 25% folder were combined using GIMP to give the animated GIF at the left.
October 7, 2020. Running on the generator again. Opened up a bit after midnight and set up on Mars with the ASI183MC and the Schupmann. (note that the Schupmann has a focal ratio of f/14 and the camera has 2.4 micron pixels). A set of 17 one minute videos were taken starting at about 12:12 AM. Seeing was occasionally steady, but mostly wildly jumping around and poorly focused. I was able to use a shutter of 1.2 ms and get over 23000 frames per one minute video. I processed the videos in AS!3, turning on deconvolution and keeping 2, 5, and 10% of the best frames for the stack. The 5% set of TIF files were sharp enough and had less noise than the 2% set, so it was derotated and stacked to give the image shown below. The 10% set was turned into the animated GIF shown to the right using GIMP.
October 6, 2020. After hooking up my gasoline powered generator to supply temporary power to my observatory, I took a set of 20 one minute videos with the ASI183MC at the f/14 focus of the Schupmann. I used a shutter of 1.1 ms and a gain of 384. Each video had 22326 frames. The videos were processed with Autostakkert!13 with selections for 10, 5 and 2% of the best frames to be stacked. Deconvolution sharpening was selected. The sharpened TIF files from the 10% folder were combined using GIMP to give the animated GIF shown at the left. WinJUPOS was then used to derotate and stack the 20 images from the 5% folder. The result is shown below. Note the prominent notch in the western side of Syrtis Major. This is an incursion of light colored dust from the global dust storm of 2018.
October 3, 2020. I had three really good sessions last night. Seeing got better as Mars gained some altitude. It was not really any better than average though. I hope the Jet Stream behaves as we get close to opposition. Last night it was blowing close to 100 mph. I was “Lucky” that Mars was bright enough so I could really keep the exposure short and collect lots of frames. I was getting over 20,000 frames in a one minute video, and 2% of the best ones gave me over 400 to stack and produce a 20x boost in s/n. I gained another factor of 3 or 4 in s/n when I derotated and stacked all the images from each of the three sessions.
September 29, 2020. Conditions were changing rapidly last night. Early predictions indicated it would be cloudy, a disappointment because jet stream velocities were predicted to be low over NJ, that normally goes with good seeing. I checked the sky at midnight, and all was clear. I waited until Mars was a bit higher and opened up the observatory a little after 1 AM and directed the Schupmann towards Mars. The view was spectacular - many identifiable albedo features were visible on the computer screen live view, no processing. I quickly tuned up the focus and the field mirror adjustment to compensate for atmospheric dispersion and started taking 60 second videos. Transparency was a bit variable, but pretty good. 2 millisecond exposures worked well. The videos were processed as usual in Autostakkert!3, with deconvolution sharpening selected and creating folders for keeping 25, 10, 5 and 2% best frames of 23644 from each video. The image below is the derotated stack of all 27 images from the 5% folder. I also used GIMP to make an animated GIF from all 27 images in the 25% folder. It is shown below the annotated image.
This is an animated GIF prepared from 27 TIF files created by AS!3 using the 10% best frames from each the 23644 frames of each of the videos taken on September 29,2020
September 27, 2020. We had the combination of poor seeing in the evening, good seeing in the wee hours, some clouds, and
high fog giving poor transparency. I started observing Mars a bit before Midnight, earlier than I had planned, and it was a good thing, because the high fog that caused me to use much
longer exposures than usual (18 ms, vs 2 ms) thickened by 12:20 or so to the point that Mars could not be seen. Seeing was quite good though and many surface features were
September 23, 2020. Seeing was only average when I lined up on Mars with the Schupmann this morning around 4:15 AM. I took 17 one minute videos with the ASI183MC at the f/14 focus. The derotated stack of all 17 images from the best 5% of 23189 frames from each video is shown below. Resolution is not as good as yesterday, however Olympus Mons, Pavonis Mons and Arsia Mons are more prominent.
September 22, 2020. Between 1:30 and 2:15 this morning the seeing was quite good, particularly with the high altitude Mars occupies this opposition. Mars is showing a LOT of detail, particularly in the Solis Lacus region. Olympus Mons is visible, but only as a lighter spot in the indicated position. The volcanoes are much easier to see when there is oblique illumination as there was in my images of September 15 and 16. Mars is getting very round as Opposition approaches.
September 16. 2020. The smoke from the fires on the West Coast have reached New Jersey. The effect was like a light overcast with some reddened light getting through.
September 15, 2020. Last night we had the unusual conditions of light smoke overhead, coming all the way
from the west coast. Not nearly as bad as it was in the midwest where my friend Ralph Taggart was only able to image Mars in the NIR. In addition, there was enough overcast or fog
that I was unable to image Jupiter around 8 pm.
September 13, 2020. Seeing was quite good this morning when I took 17 one minute long videos of Mars with the ASI183MC camera at the f/14 focus of the Schupmann. These videos were processed in AS!3 with deconvolutive sharpening turned on. The resulting images were converted into the animated GIF shown below. They were also derotated and stacked in WinJUPOS and then sharpend a bit in Registax6. This image, with annotation, is shown above. Note that Olympus Mons is directly on the terminator. A contrast enhanced clip is also shown by the annotated image with grid showing the sunlit western slopes at sunset and the shadowed eastern slopes. Looks like a little bump, but is actually the tallest volcano in the solar system.
September 12, 2020. Seeing was pretty awful last night when Jupiter was observable and transparency was marginal. I got three videos, but the best processing only gave a big smudge with the NEB and SEB barely recognizable. Waste of time.
September 8, 2020. Good seeing this morning! Maybe 4/5 rating. I took 16 one minute videos of Mars at 432fps with the ASI183MC at the f/14 focus of the 7.25" Schupmann. I processed them with Autostakkert!3, aligning and stacking the best 8% of the 25945 frames in each video and then derotated and stacked the resulting images in WinJUPOS and finally sharpened and histogram adjusted the final stack which is shown above. The overlay grid on the right is courtesy WinJUPOS. Longitudes may be estimated from this grid which is 10°x10°. The central meridian is 241.5° East Longitude. Add 10° for each grid mark to the right, subtract to the left. The grid helps considerably in identifying surface markings. Labels are a mix of traditional, pre-spaceflight maps prepared by visual observers and modern NASA maps. We know there are no seas (Mare) on Mars, but NASA has no names for some prominent albedo features that do not relate to topographic features on the planet. Mare Chronium is just part of an extended Cimmeria Terra now even though it appears as a separate region based on its albedo (brightness). The animated GIF below was prepared from the 16 images using GIMP.
A slightly better result was obtained using 3% of the frames rather than 2%,
September 7, 2020. The high altitude of Mars continues to help out with the seeing. Although only predicted to be average, the seeing was much better than I am used to getting from Jupiter or Saturn under average conditions. I took 13 one minute videos with the ASI183MC at the f/14 focus of the little Schupmann, processed in Autostakkert!3, with the deconvolution sharpening turned on. I adjusted color balance and levels in Registax6 and rejected two of the images because some of the good frames got too close to the tiny ROI I had defined of 128x130 pixels. Maybe a bit too tight. Still, I got 432 fps and nearly 26,000 frames per video with a shutter of 2 ms. I derotated and stacked 11 of the images, each of which was a stack of only 2% of the frames in the video. This is pushing my luck in lucky imaging. Easy to do when you get so many frames in only one minute of video. After minor sharpening in Registax6 I got the result below. An image with grid, courtesy of WinJUPOS is included to help identify features. Each grid unit is 10°x10°. Note the small dark blob on the projection extending down (North) from Terra Cimmeria. That tiny blob is Gale Crater where Curiosity rover is tooling around learning things. Note also the very slight bluish haze over Syrtis Major. This is high level clouds, often more pronounced than this. There is also clouds extending south from the North polar cap where it is still probably snowing. It is still late winter there.
September 5. 2020. The sky did not look very promising this morning at 2 AM, variable haze and thin overcast and a well past full gibbous moon lighting it all up. Mars was shining brightly though, so I woke up my night assistant Chewie and we went back to open up the observatory and got busy with the Schupmann and the ASI183MC. Seeing was a bit above average, 3/5 or so and Mars was bright enough so that I could use an exposure of only 2 ms. I used an auto-histogram setting of 50% to deal with the variable transparency and took a set of 15 videos of one minute duration between 06:26 and 06:40 UT and achieved a frame rate of 375 fps and collected 22516 frames per video. I processed them in Autostakkert!3, keeping only the best 2% of the frames, sharpened with wavelets in Registax6 and then derotated them all to the common central meridian of 256° east longitude, stacked and sharpened lightly again to give the result shown below. Labels for albedo features are a mix of traditional and NASA names.
August 31, 2020.
Seeing was quite good when I got up at 2 AM to image Mars. I took 15 videos between 0620 and 0635 UT and worked them up
using Autostakkert3 to align and stack the best 3% of the 21720 frames in each of the 60 sec videos with 1.5x drizzling selected to give better sampling. These images were sharpened with
wavelets in Registax6 and then all 15 images were derotated and stacked in WinJUPOS to give the annotated image shown below.
August 24, 2020.
August 11, 2020. I got up in the wee hours this morning and captured 11, one minute long, videos of Mars using the ASI183MC at the f/14 focus of the 7.25” Schupmann. Seeing was below average but usable. My shutter was only 2 ms and I used a tiny ROI of only 128x128 pixels. This gave a frame rate of 437 fps and allowed the capture of 26,230 frames in each of the one minute videos. The best 5% of the frames of each video were aligned and stacke in Autostakkert3 and sharpened in Registax 6 then all 11 images were derotated and stacked in WinJUPOS and finally sharpened slightly in Registax. The annotated result is shown below. It is evident that a lot of dust got blown around back in 2018 when the global dust storm happened. The dark albedo feature Mare Sirenum and surrounding region looks different from my images from previous oppositions and the BAA maps. Will try to verify the changes as Mars gets closer. There are a couple of light spots near the terminator which I thought might be the sunlit western slopes of a couple of the Tharsis ridge volcanoes lit up by the setting sun, but the coordinates aren’t quite right. An animated GIF was also prepared from the 11 images and is attached.
Above is an image made with only 2% of the frames of one of the videos, but with less sharpening in Registax. Less of the edge artifact, but the albedo features are less visible. You win some, and you lose some...
July 27, 2020.
June 20, 2020. After Jupiter had vanished behind a tree and when I had finished with Saturn, I noticed Mars peeping above the trees to the southeast, well up in the sky. Got several 90 second videos of it, my first this opposition. Even though Mars is still quite small, a lot of detail (and no sandstorm) is showing up. Nice bright south polar cap, Hellas is bright and not obscured by dust or clouds. After derotating and stacking the 5 images, more detail emerged, in spite of the fact that Mars is now only 10.24 arc seconds across. The central meridian of the images is at 298.4 degrees and we are looking at a point 23.8 degrees south of the equator. Chasma Australe, an ice free region extending almost to the pole is visible as a dark wedge extending into the polar cap. The dark albedo feature is Syrtis Major near the terminator on the east. Hellas is prominent and neither covered with dust as it was early in the season nor white clouds. The annotated image of Mars is the first attachment.