“Combo-bite”

When the grandkids were young, one of which still is, we often resorted to offering “combo-bites” to get them to eat some things they may not have otherwise eaten. Obviously, a combo-bite is a bite that contains more than one type of food. In today's entry, the combo-bite is a combination of two of my hobbies: amateur astronomy and amateur radio. I'll start with the radio, which was the reception of an image via slow scan TV from the International Space Station. The image was one of several sent from the ISS celebrating the 20^th anniversary of amateur radio on the ISS, referred to not surprisingly as ARISS. This was the image sent at 10:46 EST (1546Z) and is one of many different images sent from the ISS. Obviously, the ISS needed to be flying overhead, so I used the Heavens-Above.com website to track the ISS to know when it was overhead and for how long it would be visible (usually about 10 minutes). The most I could get in any one pass was 2 images. I was able to receive 8 such images, 6 of which are different. Had I been willing to stay up around the clock (I wasn't), I could get a pass about every 90 minutes and received lots of images. However, I think the ISS was transmitting only about 6 to 10 different images, and I suspect it would have become something less than fun around 2AM. Anyway, here's the 12/26/2020 1546Z image, which was the best of the 8 received.

Image from International Space Station, via SSTV

The other image for today was inspired by the first activity. On the images received on December 29^th, I noticed a fair amount of noise. At the time, I wondered if the noise could have been caused by solar activity. I remembered later that, while possible, it was highly unlikely to have been caused by the sun that day. None the less, I decided to look at the sun. There was more than usual activity, so I tried to image it. Results below.

An Unusual Image AND Learning Experience

The subject of this image is NGC1893, located in the constellation of Auriga. The NGC object is an open cluster of stars, but has a Hydrogen-alpha region associated with it called, apparently, IC410 and SH 2-236. In my image, the predominant red region is IC410/Sh 2-236. Separating the open cluster from the background stars is more difficult.

NGC1893. What's that on the right side of the image?

So, what makes this image more interesting than usual? The story begins three nights before when I imaged the same object. However, I imaged at (binning of) 2x2 for the luminance channel, and 4x4 for the red, green, and blue channels. The idea was multiply the RGB channels by 2 to match the L channel, then combine like I usually do. Turns out, that's not possible. The image in 2x2 is 1663 pixels wide, while the 4x4 are 831 pixels wide. And never the twain shall meet. One lousy pixel off, and I had to throw the RGB channels away. Such is life. So, after finding this out, I re-shot the images, (LRG&B) again on the 8^th. Turns out, that makes things more interesting. Lesson #1, don't shoot 2x2 and 4x4 and think they can be combined. In my experience, shooting stars with underlying or nearby nebulosity can be problematic; either the stars are over exposed, or it's extremely difficult to bring out the nebulosity. Or both. Bringing out the nebulosity was the case this time. Certainly not APOD quality, but probably as good as I can do under the circumstances. Now things start getting very interesting. Looking at the bottom right corner of the image, there is something that looks like a grey “wand” that changes to red, green, and finally blue. That really is a thing and it took me about a half day to find out what was going on. I figured it might be an asteroid moving across the field of view, since the entire run for shooting this image was about 2 ½ hours. I tried several web sites to try to determine what asteroid it could be, but to no avail. It turns out the at least one of the suggested web sites needed the coordinates of the center of the image to try to figure out what the moving object could be, so I tried my old friend ASTAP. In this case, it was ASTAP to the rescue. ASTAP can also figure out what comet of asteroid is in the image, so I downloaded the needed files and decided to try it. Turns out it wasn't an asteroid, but a comet. The line is comet C/2020M3 Atlas. So, why is it a line? The 1^st hour of imaging was done in the L channel, hence the grey line. Then, 20 minutes each of red, green, and blue, which make up the remainder of the multicolored line. There you have it. Mystery solved, and I learned a method of identification of asteroids and comets in an image. (end of lesson #2) Below is the ASTAP plate solved image, showing what I found on ONE of the many L channel images. Notice the circle annotated D0 18. Another mystery and one with little information. As best I can find out, that refers to a Dolidze catalog, entry # 18, which, apparently is a catalog of open clusters (end of lesson #3). Who knew? (Well, I do now.)

 

ASTAP Plate solved image above.

Tuning Effects

 One of the adjustments on my solar scope (Coronado Solar Max 2, double stack) effects the “tuning” of the scope. Truth is, that is the primary thing that can be adjusted, other than the focus. The object of tuning the scope is to allow the user to obtain more contrast on objects, eg sunspots. The tuning appears to be rather sharp. I often see the effect as the brightness spread across the face of the sun. Today, I took several images of the sun. However, a major difference today is the sun is too low to ride piggyback on the LX200GPS, so it is used as a stationary scope. Of course, that means that the sun drifts across the field of view of the scope. With no tracking (of the sun), stacking becomes more difficult and, generally, the images suffers from “motion blur”to some extent. With that in mind, what I want to show, is the effect of changing the tuning on the scope. As there is no method of measuring the difference in tuning, the best I can do is just show the effect. So, image 1 is with the tuning one way; image 2, another. Note the increased detail, however, in image 2. One of the main things the tuning does is change the center frequency of the light coming through the scope. Elements with doppler shift can disappear if tuned out of the bandpass of the scope. That's basically the effect seen in image 1. The bandpass was changed to favor the right hand side of the image, so elements barely visible in image 1 are now more easily visible in the 2^nd image.

 

Image 1. Note the white, hotter, area around the sunspots and prominence about 5 0'clock.

Image 2. Much more to be seen.

 

Some Catching Up

 There are several deep sky images taken and processed that I have yet to put on the blog. Today's entry is something that should have been appropriate for Halloween, perhaps. Its NGC7380, the Wizard Nebula, aka Harry Potter and the Golden Snitch. I can't say how it came by either of those names, but I guess that's why I don't name nebulae. NGC 7380 is a young open cluster of stars in constellation of Cepheus, discovered by Caroline Herschel in 1787. The surrounding emission nebulosity is known colloquially as the Wizard Nebula. The nebula is known as S 142 in the 1959 Sharpless catalog. It is extremely difficult to observe visually.

 

NGC7380 (open cluster of stars) and Wizard Nebula (S 142)

 

Views of the Mars

Finally, in this series, we have 2 nights of Mars. First from October 21, 2020, which apparently had the less good seeing of the two nights. Image taken at F10 (with the 8” LX200GPS). Then, the second night was November 9, 2020. I took one image at F10, the second at F20 for comparison. The seeing was good enough that I think the F20 image might be the better of the 2.

Mars, October 21, 2020. F10.

Mars, November 9,2020. F10.

Mars, November 9, 2020 F20.

Views of the Jupiter

 
Continuing …. Jupiter is continuing its westward movement in the evening sky. I my case, that means further towards the roof of the observatory. Problem with that is, the air rising from a somewhat hot roof will distort the air, essentially increasing the seeing, making it worse, of course. The first image is from October 21, the second from November 9, 2020. The blurring effect from the rising air is obvious. The November 9^th image is a composite of two images; one taken to get the better image of Jupiter, the other, taken as a longer exposure, to get the moon.

Jupiter October 21, 2020

Jupiter November 9, 2020. Composite. Moon most likely Io.

Views of the Moon

 Continuing posting from images taken since the last major posting, I took images along the terminator of the moon on October 21, 2020. Unless I have a specific target in mind, I “run the terminator”. Afterwards, I look for interesting things; things I haven't seen before. Often the way the light strikes the moon, subtle differences in shading will show different things. This is the case for me on the image below. I see an inverted “Y” is the shading emanating from the crater Cook B. The feature is visible in Virtual Moon Atlas, but is not as prominent in VMA. At any rate, the lower image is the same as the upper one, with the “Y” drawn in.

October 21, 2020. Cook B.

Inverted "Y". See if you see it in the above image.