M42 - Orion Nebula

Two weeks ago I posted a blog about the interference from the Starlink satellites on my astro imaging sessions. In that article I explained how the post processing software effectively removes the satellite trails from the images. 

Well here is the final result of those evenings of imaging M42 and the Running Man nebula. I was going to add in some Ha subs, but the result didn't look as good as the standard LRGB.

M42 and the Running Man Nebula - Jan 10-13, 2021
WO GT102 and ASI1600 MM Pro
148x30sec L; 89x30sec R and G; 94x30sec B

Dealing with Starlink Satellites

Starlink is a satellite internet constellation being constructed by SpaceX providing satellite Internet access. The constellation will consist of thousands of mass-produced small satellites in low Earth orbit, working in combination with ground transceivers. Wikipedia 

Well, that's good news for the needs of the public to gain access to the internet, but its bad news for the amateur astrophotography crowd. It turns out that these satellites can be quite bright and therefore a big problem for ground based observers. And because they are in low earth orbit and there will be lots of them (Starlink alone will consist of 12,000, and other companies are considering satellite constellations of their own) we may not be able to see any part of the sky that doesn't have a satellite passing through.

Astrophotographers take long exposure photographs (some exceeding 10 min in length) to capture the light needed to produce a good image. During that time, plenty of satellites could pass through the field of view and potentially ruin the image. 

In the past few weeks I have started to notice a considerable amount of Starlink satellites passing through my night sky and ending up in my photos. Here is a video of my last set of images of the Orion nebula taken on January 14. This video is a time-lapse of 20 images, each 5 minutes of exposure time (the typical time I use with my camera). You can see the Starlink satellites passing through on the far right, with another, unrelated satellite, passing through the center. This will only get worse as the number of satellites increase over the next few years.

However, all is not lost. Because of the post-processing done on astro images (see my post on image processing here) I take up to 100 subs to combine into a single image to increase the quality of the final photo, decreasing noise and increasing signal. This process can detect which pixels on the image appear on every sub (the signal) and which appear on only one sub (noise, or, in this case, a satellite trail). The processing then stacks the subs together but removes the unwanted pixels. 

Rejection-high

In the photo above, all the bright spots, streaks and lines are the pixels that were detected by my software as present on only a single sub (or were overexposed regions). These will be removed from the final image. You can see the lines of satellite trails on the right and the one that passed through the center. There are some spots throughout the image that will also be removed. These are overexposed areas of the image which are also removed as part of the processing.

The following photo is the processed image where the unwanted pixels were removed.

So, although the proliferation of these satellites will be a challenge for astro-photography, it can be managed. The software we rely on to stack and process our images does an amazing job in tackling the issue of these unwanted photo bombers!

A couple of planetary nebulae for you

Just got finished unloading the EdgeHD11 and re-mounted the GT102 on the AP1100 to image some winter wide field objects. With the weather as it is lately, I spent some time processing some images I took weeks ago (I actually have a backlog of images to process due to that string of clear nights awhile back).

Here are two planetary nebulae, IC 289 and NGC 1514, known as the Crystal Ball Nebula.

Planetary nebulae (PN) are poorly named - they are not planets! They are the remains of intermediate-mass stars. As these stars run out of fuel, they expel their outer layers of hydrogen, oxygen, sulfur and other gases. The result is a small, short lived (astronomically speaking of course) sphere of rapidly expanding hot gases, while the source star collapses into a super dense white dwarf. In many PNs the central star can be easily seen. 

PN appear rather small in the sky, hence the need for a large telescope to pick them up. But they are also fairly bright. Since the main components are ionized hydrogen, oxygen and sulfur, narrowband imaging is ideal for these deep space objects.

First up is IC 289, a small PN in the constellation Cassiopeia. Located about 5000 light years away it is 40 arc-seconds wide (about 1/100 degree) which makes its diameter of 1 light year.

IC 289 - October 8, 2020
EdgeHD11 with ASI1600mm Pro; f/11
35x300 Ha; 45x300Oiii

For this object I imaged using the Ha and Oiii filters (I rarely spend time with capturing the sulphur component, Sii, as it is typically very faint compared to the Ha and Oiii subs). I captured 35 five minute subs of Ha and 45 of Oiii. I used the HOO palette, mapping the Ha to red and the Oiii to blue and green. 

Next is NGC 1514, the Crystal Ball Nebula, found in the constellation of Taurus the bull. It is 2000 light years away and spans a bit over 3 arc-minutes (1/20th a degree), which corresponds to a physical diameter of 2 light years across.

NGC 1514 (Crystal Ball Nebula) - Nov 9 and 17, 2020
EdgeHD11 with ASI1600mm Pro; f/11
49x300 Ha; 50x300Oiii; 29x120 R; 30x120 B; 30x120 G

As true in most PNs, I imaged this in Ha and Oiii as well, but also added some broadband (RGB) subs as well - 49 five minute subs of Ha and 50 of Oiii combined with 30 each of 120 seconds in RGB. 

There are many more PNs to image, but for the next few months I'm moving back to wide field with the 102mm APO. 

The Most Famous Paradox in Physics Nears Its End

In an article by George Musser (QuantaMagazine, October 29, 2020) it seems we might be further along in solving the paradox of contradicting results between General Relativity and Quantum Mechanics when dealing with black holes. In a landmark series of calculations, physicists have proved that black holes can shed information, which seems impossible by definition. The work appears to resolve a paradox that Stephen Hawking first described five decades ago.

Ashley Mackenzie for Quanta Magazine

According to Einstein’s general theory of relativity, the gravity of a black hole is so intense that nothing can escape it. In the 1970s Stephen Hawking and others sought to describe matter in and around black holes using quantum theory (although they continued to describe gravity using Einstein’s classical theory — a hybrid approach that physicists call “semiclassical.”) These new insights of Hawking provided some interesting effects on the boundary of the black hole, but still left the interior as 'unknown'. Hawking claimed that at the quantum level, things can escape the black hole (Hawking radiation), eventually leading to a complete evaporation of the black hole in time.

The article describes some very interesting work done recently to bring the two theories together. The trip is a wild one - Page Curves, Multidimensional quantum wormholes, and other weirdness-es steeped in  reality and getting perilously close to fiction. Read the full article at QuantaMagazine. Easy enough for the layman to comprehend, provided you read slowly and try to visualize the concepts. 

New Equipment - Part 2

With a clear sky and full moon I decided to spend the majority of the early evening on Dec 29th to get the remaining software device drivers installed on the new NUC.  Needed to have the equipment connected to do that, so I had to set up the telescope. For some reason I decided I would replace the EdgeHD11 with the GT102 APO that night as well since I eventually want to image some winter nebulae. 

One lesson I should have learned by now is that you shouldn't try to do everything at the same time. I had completely forgotten that in order to mount the GT102 I needed to reset the mount point of the dovetail plate on the mount. By the time I got the mount reset, plate screwed down, and telescope balanced, I had spent about 2 hours of time. I did eventually load the software drivers and configured everything to run on the new NUC. It was time to run a short imaging run to test things out. But by the time I was set, the clouds moved in. Oh well, at least I'll be ready for the next clear night, hopefully soon. 

New Equipment (aka, a Christmas Gift)

Merry Christmas to all. I trust you all had a wonderful Christmas. 

With the Great Conjunction now over (I'm still a little bummed that I didn't get any photos) its time to start working on the next full year of astroimaging. Both 2019 and 2020 have taught me that NUCs (Next Unit of Computing) mini PCs work really well as pier-side computers for running your telescope equipment. But it also taught me that, like in all other areas of technology, astro gear improves over time. My Minisforum GN34 NUC has served me well over the past months, but there were plenty of nights when the unit's speed and capacity were strained with what I was trying to push through it. So I asked my better half for a new one for Christmas, and she knew just which one to get!

So today, after the rest of the activities were done, I started to load up my software on my new BeeLink U57. This unit boasts a 5th Generation Intel Core i5 processor, 8GB of memory, a 256GB SSD and of course plenty of USB3 ports, WiFi, BlueTooth and Ethernet 1000 Mbps LAN, all in a box 124mm x 113mm x 41mm. Comes with Windows 10 Pro, so remote logins are easy.

Software is all loaded and tested. The speed is a large improvement over the GN34. Now I just need some clear skies to put it through the paces. The only annoying part of the adventure so far has been the discovery of the power connector on the NUC. I have custom cabling that runs all my 12v power to my telescope equipment thru Anderson Powerpole connectors and 2.1mm plugs. Of course, Beelink decided that their unit would use a 2.5mm plug. So for this weekend I'll need to run the unit via the supplied 120v to 12v adapter until my new cables come from Powerwerx.

Great Conjunction

No images for me - the weather just would not cooperate, at least for imaging.  Tried again on the 22nd but no luck.  Some friends dropped by and we all got to view the conjunction for a few minutes while there was a short break in the clouds.  My GT102 with 13mm and 8mm eyepieces provided a wonderful view.

Great Conjunction of Jupiter and Saturn

You know, rare astronomical events events occur whether we can see them or not!  Yeah, profound statement (well, maybe not too profound).  But, regardless, such is the life of an amateur astronomer.

Had the telescope and camera gear out on the 20th (since the weather forecast for the day of the event was for overcast skies).  Set up just outside Westminster MD, on the parking lot of my church.  It was very cloudy, but the Lord provided a sliver of clear sky so that I (and the guests I had with me) were able to see the 'near conjunction' visually.  Getting the camera set-up was problematic, and by the time I had the system up and running (software glitches), clouds covered the scene. 

The view was awesome!  Both Jupiter and Saturn were clearly visible, displaying their respective details - Jupiter's cloud belts and Saturn's magnificent ring system. The GT102 (with only 703mm focal length) only provided a small planet size, but no matter, both planets (and a collection of Jovian and Saturnian moons) were present in the same eyepiece field of view. It was worth it!

With Tuesday night promising some clear skies I will try again to image this wonderful event. Yes, they won't be as close as on the 21st, but still should make for a great shot if I can get both planets and the moons to show up in the same image.

The Great Conjunction of Jupiter and Saturn

Jupiter and Saturn Conjunction - Dec 21, 2020

Just after sunset on Monday, December 21, 2020, our two largest planets will come closer to each other than they have in almost 400 years. A conjunction happens when planets appear very close to one another in the sky because they line up with Earth in their respective orbits. Over the past few weeks, Jupiter has been closing in on Saturn's position. And on December 21st they will be the closest since 1623. 

Will they appear as a single "Christmas Star"? Not likely. If you have good eyesight you should be able to make out two distinct points of light, with Jupiter outshining Saturn by 10 times in relative brightness. Look southwest, about a half-hour after sunset (5:15 pm). The planet duo should be visible in the darkening sky. You will need a clear view as the pair will only be 15 degrees above the horizon. Binoculars and small telescopes will reveal a splendid sight, and with sufficient magnification you'll be able to see both planets — Saturn with its famous ring system and Jupiter with its cloud bands and Galilean satellites — simultaneously in the same field of view!

Typical field of view in a moderate telescope at 350x

I will be attempting to photograph this event from my location in Maryland. Using a William Optics GT102 refractor and ASI462 camera I should be able to capture both planets in the same frame.

More detail about this event at Space.com

Mars 2020 - The Magic of "Lucky Imaging"

The best opposition of Mars until 2035 has just passed with the best times to view and image the red planet between late September and mid October. The weather cooperated (mostly) and we were all treated to a wonderful display (without the giant dust storms of 2018).

I was out every chance I got to image the planet when it was the closest and brightest. Mars was well placed, high in the sky. As reported back in early September I imaged Mars with my new ASI462 for the first time. Results were pretty good, but could be improved. Based upon what I've seen on the various astro-boards, my image was about a 4 on a scale of 1-10.  

I imaged Mars on five nights, Oct 2, 13, 14, 21 and 22. Results were generally bad to awful. But on the 22nd I was able to get a respectable image.

Planetary photography is a tricky business. Lots of things can go wrong, and frequently do. The real culprit is the fact that we have a thick atmosphere above us. The twinkling of the stars on a crisp clear winter night is evidence of that atmosphere. Stars are very big, but they are incredibly far away. So far away that they appear as points of light, even in large telescopes. As the narrow beam of light makes its way to the observer it has to pass through various layers of the Earth's atmosphere. As it does the light is refracted and bent to and fro. What we see over time is that beam coming to us from various angles and that makes the star twinkle. 

Since planets are close enough to us that they appear as a disk (although you'll need a telescope to see that), the twinkling effect doesn't occur. Since the disk is composed of lots of beams of light, each randomly refracting, but all in different directions at the same time, we see the combination of all them. Thus, instead of a twinkle, planets appear steady. But the disk image distorts over time because the beam combination is different as the air moves between us and the planet. These random fluctuations of the light are a big problem - they cause the planet's disk to 'bubble' and 'wobble' in the telescope's field of view. You may be aware of this if you've ever looked in a telescope or pair of high power binoculars at a terrestrial object during the heat of a summer day. The object appears to rapidly move about; sometimes appearing blurry but every now and then sharpen to crystal clarity (Outer Limit's fans will recognize the phrase). 

So, planetary imagers use a technique known as 'lucky imaging'. This technique is used to record hundreds or even thousands of images over a short time span in order to capture some images when the seeing is momentarily steady. In order to capture this many images in a short period of time though we need a camera capable of high speed imaging. The ASI462 is one such camera - a video camera for astrophotography. But, just like with deep sky imaging, the process is rather involved.

On the evening of October 22 seeing conditions were pretty good, about 3 or 4 on a five point scale with 5 being the best. My location is not all that great for planetary imaging since my telescope location is within a 'bowl' of terrain surrounding by trees, and the denser air settles and swirls about around my property. I set up and waited for the scope to reach ambient temperature and for Mars to rise higher in the sky (the higher the better - less air mass to image through). 

At 9:53 PM I set the system to capture Mars over a total exposure period of 6 minutes. The camera was set to take 45 frames per second, at 5ms per frame. I was able to capture 27,415 images on this run.

Here is a sample of 50 frames from the beginning of that run. This video was taken with my ZWO ASI462 through an EdgeHD11 telescope equipped with a Televue Powermate 4x teleconverter. This makes my EdgeHD equivalent to an 11" f/40 (11700mm) telephoto lens!

As you can see the image moves quite a bit. But this is actually a nice run. But even in the short 1-2 second clip you can see areas of the image that appear sharper for a fleeting fraction of a second. With over 27,000 images all we need do is locate the best images from the set. That's where AutoStakkert comes in. 

AutoStakkert is an image stacking software. As the author Emil Kraaikamp puts it: 

"AutoStakkert!  is all about alignment and stacking of image sequences, minimizing the influence of atmospheric distortions (seeing). Its goal is to create high quality images of the Planets, the Sun, and the Moon, without too much hassle".

AutoStakkert takes the video and processes the individual frames finding the 'best' of the bunch as per specific parameters set by the user. I usually ask for the 20% best. If the time is kept short, this is all that needs to be done to get a stacked image of the selected frames. But since I was exposing for a full 6 minutes, the rotation of the planet needs to be taken into account. After all, Mars rotates almost the same as Earth; 24 hours, 39 minutes, and 35 seconds to be exact. In a period of 6 minutes, Mars would rotate about 1.46 degrees, probably enough to cause some blurring of the image (although considering all the other factors I had to deal with, probably unnoticeable). To compensate for the planet's rotation, I use another software tool called WinJUPOS. This tool will take the video from AutoStakkert, along with the stacked image, and de-rotate it so that the movement due to planetary rotation is cancelled. This de-rotated version of the video is then reprocessed once more with AutoStakkert to produce a final stacked image. In my case, 5,483 frames of the original 27,415. The resultant image is shown below:

With the stacked image and de-rotation taking care of much of the seeing perturbations we now have a much cleaner image. But it's still not as sharp as we would like; the air turbulence is still causing some blurriness. The detail is trying to come out.

Next up, and the next to final step in the imaging process is to apply discreet wavelet transformation on the image to remove as much of the noise as we possibly can and sharpen the image, bringing out the details that are there, but covered up by the noise in the image. I do this with a tool called Registax. Once the proper parameters are set (which in itself is a time consuming trial and error process) the final image comes to life - and the results are magical.

Mars 10/22/2020 - EdgeHD11 fl=11,700mm
ASI462 - 6min - 5,483 frames

A final pass with Paint Shop Pro to enhance the color and adjust the brightness and contrast and I'm done. A rather successful night. Still not as good as what I see other amateurs accomplishing, but good enough for me. In the image you can see the polar cap, Mare Sirenum (the dark patch just to the right of center) and Amazonis the bright area on the bottom half. The most recognized region, Syrtis Major, is on the opposite side of the planet when this image was taken. It will be centered in early to mid November, and if the skies are clear I'll attempt to capture one more image for the record books. Mars and Earth will be separating rapidly during the next few weeks and so the image will be smaller. 

Cosmic Strings from the Big Bang?

Not much happening in my astrophotography endeavors, other than I'm busy processing the data I captured from the 5 straight nights of clear skies - thank the Lord!

But I came across this article in Quanta Magazine which was a real eye opener. Has to due with the possibility that cosmic strings may be giant filaments left over from the birth of the universe. Strange stuff ... read the article here:  Quanta Magazine.  Go there even if you're not interested in string theory - the opening graphic is awesome.