On November 24 a supernova was discovered in the galaxy M77. Named “SN 2018 ivc” it is the only supernova to date discovered in the brightest Seyfert galaxy we know! M77 is an active galaxy with a quasar-like nucleus. It is pretty bright for a galaxy, about 9th magnitude, and is located in the constellation Cetus. A supernova discovery in a Messier object is pretty rare, and as it just so happened I had started an imaging project at Orion’s Belt Remote Observatory on the galaxy when one of the Astronomical Society members alerted us to the discovery! The supernova is a “Type II” which is distinguished by the presence of hydrogen in the spectrum. (Perhaps a spectroscopy project for a future event!) I was able to locate the star in one of the 15 minute frames I had taken of the galaxy (see below). Initially it was around 14-15 magnitude, located pretty close to the core . In the image I obtained nearly 2 weeks later it does not appear to have changed significantly in brightness.
Recently I was browsing an online astronomy journal when I came across an advertisement for a remote imaging site in Chile: Chilescope.com. It was an attractive home page and of course being an avid astroimager I know about Chile, arguably the hottest property right now and home to all the latest and greatest ground based telescopes in the world. The Atacama Desert, driest place on Earth, could be the best observing site without actually being in outer space! Now I already own and operate a remote observatory in Mayhill NM, the birthplace of remote imaging so why would I be interested in anything else? Probably the main interest lies in the fact that I cannot observe the southern hemisphere’s sky from here! The fact that it is Chile adds a certain mystique to the whole picture. I decided to look into it further. The observing site is located in a remote part of Northern Chile. The nearest town is Ovalle, Chile which really isn’t that close to the Atacama Desert. It’s actually a good 700 km to the south.
Ok, perhaps I was a little disappointed, but after further research I discovered it still lies in an area in the North where the weather is superb and the climate is still quite dry. The site sits at a modest elevation of 5000 feet so quite a bit lower than anything in the Atacama region. The project was started by a group of astronomers in 2013 in collaboration with the University of Santiago.
Three observatories that were built are available for use. Two of them house identical telescopes and equipment, consisting of extremely fast (F3.6) ASA 20” Newtonians with direct drive mounts and FLI 16803 cameras.
The third observatory houses a 1 meter RC scope! The site is directed toward amateur astronomers but also caters to professionals who are looking for quality telescope time. I am not generally familiar with “pay for play” telescope rental sites except for perhaps itelescope, which has, in my opinion, a very complex user interface and payment structure. This by contrast is extremely clean and simple. The cost for use of one of the Newtonians is 60 dollars per hour which is quite a bit cheaper than what I have seen for other sites. They provide the usual “Moon discounts” for imaging in moonlit skies. They also credit observers for mechanical problems and even bad frames. My estimate was that you could conceivably do a decent tricolor image project with the fast optics and discounts for perhaps around $400 or so. I then looked at the calendar of availability expecting a long wait time but was surprised to see that I could start observing the next day! Of course the next thing to inspect was the images that were obtained by users. These were absolutely tremendous APOD quality images all the way! I was sold! A chance to image the famous Centaurus A galaxy and other renowned southern hemisphere gems! Luckily I had just sold some astroimaging equipment so I had some discretionary funds to test this out. My first target was of course Centaurus A! Payment is through PayPal either from your own account or via credit card. You have to register of course first and then your payment shows up as “chile points” where 1 point equals 1 US dollar.
The user interface is very simple and they walk you through everything.
The weather is recorded here as “unsuitable” but that is because it is during the day. You set up your times based on calendar availability. You have to check with your favorite planetarium program when your object will be visible. I use Stellarium, which actually has Ovalle, Chile in their database! They do not image below 30 degrees so if your set up times are problematic either because of object visibility or conflicts with sunset or sunrise you will get an error message. Also of note is the late sunset time, around 9 oclock or so.
Remember it is Fall down there and they do not observe Daylight Savings! Currently you can easily image for 4-5 hours. They do reserve about 2 hours or so for non imaging functions. All of these details are explained both on the site and in a downloadable PDF . If you have any experience at all imaging the set up page is a snap. You enter the RA and Dec coordinates of your target, enter the number of subs you want to take, filter, binning, exposure time, how often you want to focus and even dithering. That’s it! When your session starts you get an email with a link to the session log which you can follow. At the end of your session your files are available for download. You can also download your bias, darks and flats at any time for free. They update their flats every week and darks every 2 weeks.
And now the results! This is a single 20 minute raw luminance image at 1:9 scale. The image analysis below shows the average FWHM is about 2.3 with this image scale (1 arc sec per pixel) which is close to the lowest resolution I have seen here:
They tell you that their system is optimized for 20 minute exposures so that’s what I chose. On my first session there was a technical glitch and seeing was not good that night so I did get a 30% refund based on the number of frames I lost and/or had to throw out. Their customer service is outstanding. Emails regarding any issues are handled anywhere from within 1 hour to maybe a few hours but always resolved before the next imaging session. I checked all of my images in Pixinsight and my conclusion was that resolution in general was outstanding. On the best nights it was typical to obtain single 20 minute subs with an average FWHM in the 1 arc sec range. Less than great seeing was in the low 2’s. As mentioned the system is very fast and as a result is perhaps undersampling a bit with only a 1 arc sec per pixel image scale. The focal length of 1900mm (corrected) at F/3.6 demands precision focusing as the critical focus zone is a mere 20-30 or so microns! Consistent perfection in star quality is probably not realistic given this type of optical set up with the need both for absolutely perfect focusing with a minimal error margin, and field correction for a 20 inch Newtonian! As a result about 1/5 of the images I obtained had oval appearing stars in the very corners of the field at full resolution but I actually only had to discard a few that were frankly bad. The rest were acceptable to where I felt after processing would not be noticeable. The corrected field is 50mm so it is quite large considering the size of the optics! The other problem that came up was occasional failed plate solving which caused shifting of the target off center. These frames were credited back to me no questions asked. I was actually relieved to see that I am not the only remote observatory operator that has issues to deal with! The one variable there which seems to cause no trouble at all is the weather. I am into my second week of imaging and I still have not seen a single cloud on their all sky cam!
In conclusion I would highly recommend this site for anyone who wants to image targets that can only be seen or optimally seen in the Southern Hemisphere. The cost is not prohibitive and the fast optical system makes it possible to obtain enough quality data in a reasonable time frame. The seeing at this site in Chile is excellent, and the resolution and image quality obtained make it well worth the expense, not to mention the excitement of seeing these amazing objects which we cannot see from Northern lattitudes! The user interface is very simple and customer service is superb. While you will have to throw out some subs like we all do at times, most of these will not come at additional cost. Best of all…they add 20% to your initial deposit if you are a Cloudy Nights online astronomy forum member!
Thanks for reading!
One of the things a lot of people don’t realize is that you can have the most optically perfect telescope in the universe but chances are you will never realize that potential as long as you are Earthbound! Imagine lying at the bottom of a swimming pool looking toward the surface, let’s say 8-10 feet above you and trying to see the pattern on someone’s bathing suit who is floating on the surface of the water. Practically impossible unless there is literally no wave movement in the water between you and the swimmer! That is the quandry earthbound astronomers have to deal with, namely “astronomical seeing” Because we have an atmosphere above us which swirls and twirls with turbulence, jet streams etc , the result is twinkling and blurring of astronomical objects. This is why ground based observatories are located on mountain tops. Now “seeing” can be measured. When starlight travels through the atmosphere it goes from being a point of light to a disk of light. The larger the disc, the worse the seeing. The disc of light when plotted on a graph of width vs intensity has a shape shown in the diagram below. The astronomical measurement. The “full width at half maximum” of the optical intensity of the seeing disc is the most common measurement of astronomical seeing. This is the best angular resolution that can be achieved under your current conditions. Typically measured in arc seconds which is the standard angular unit in astronomy, the theoretically best possible seeing you can have on Earth is probably around 0.5 arc seconds and can only occur in places like Mauna Kea on the Big Island of Hawaii, the Atacama Desert in Chile and a few others. Here in Mayhill , New Mexico, we supposedly have really great seeing. I mean New Mexico Skies in all there promotional ads boasts of 1+ arc second seeing regularly. Since setting up my equipment here at Orion’s Belt which is literally a stone’s throw from New Mexico skies, I have been very curious about this. So far with my larger optical set-up I have not yet seen that amazing seeing they are claiming! Could it be that it really is better just across the street? Or maybe global warming has changed the climate here? Or maybe they are just full of it and perhaps it is not as good as they say. Or maybe my set up is not optimized to take advantage of the seeing. Maybe there is a tracking glitch or my mirror isn’t cooled down close enough to the ambient temperature or there is wobble in the pier or thermal effects from the observatory floor. So many variables to sort out it makes your head spin. That’s why I decided to resolve these questions by using a “seeing monitor”.
Seeing monitors have been around for as many years as professional observatories. Most professional observatories use the Differential Image Motion Monitor (DIMM) technique to measure seeing. This technique is implemented in hardware by using a two hole mask over an 8 to 11 inch Schmidt-Cassegrain telescope aperture, and measuring the root mean square (rms) fluctuation of the spacing of the two spots seen when a bright star is imaged a little bit out of focus with a fast camera. The reason two spots are measured is that the aggregate motion of the two spots due to poor tracking or wind vibration can therefore be rejected. However, the resulting system is complicated to automate, and invariably requires an automated enclosure to house the telescope as well, running the total cost up to many thousands of dollars. Amateur seeing monitors typically use a fixed single aperture system staring at Polaris, mounted on a heavy solid base. This way the wind motion and tracking error is gone. Polaris does move across the space of a measurement, so the linear drift of the centroid of Polaris’s position is determined and corrected. We call this the SIMM technique. Very smart people have developed software to interpret the data from these monitors and calculate the seeing. My set up employs a basic amateur ccd camera mounted on a metal base. This is a QHY 5L-II camera, a 1.2 Megapixel MT9M034 CMOS with exceptionally high (74%) QE and exceptionally low (~5e-) read noise. A 100MM F 3.5 is mounted onto the camera. Just to get a sense of where I was at with seeing vs what kind of imaging results I was getting I decided to mount the monitor on my AVX mount which I felt was stable enough for a test, plus I could more easily locate Polaris in the field of the camera. The Clear Sky Clock was forecasting average seeing conditions. Once I installed the camera and software, I started running the monitor over a period of several hours while at the same time continuing my current imaging project with the 16” scope. I was able to compare the results of my individual frames with the seeing recorded at the time the images were taken. The seeing results can be seen below. My images can be read by a program which can tell me the average full width half max values of the stars in the image. Basically what I discovered is that for that particular evening there was a range of seeing conditions which started actually pretty good, then declined and recovered a bit later. My images reflected almost exactly the changes in the seeing conditions and I was relieved to see that when the seeing was good, the image results were not far off from the local seeing conditions, maybe a half arc second on average. The imaging result is going to be affected by your system tracking, flexure of your optics etc so you have to expect a small degradation in the fwhm number. I would say 0.5 arc second above the local seeing is pretty good for a large amateur optical set up. Overall I would say the first test was a good one! I don’t think I have to sell everything and move or give up on my own set up. Not yet anyway!
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At last, after months of gremlin battles we finally achieved first light for the RiDK 16″ scope! For details on the battle itself you can read the blow by blow in this page. This is a 10 minute guided luminance image of IC 5146, the “cocoon” nebula, a combination emission and dark nebula 4000 LY away in the constellation Cygnus. I picked this object mainly because there are a good number of stars and it is well positioned high in the sky at this time of year. Seeing was a marginal average and what I am discovering is that imaging at this focal length of 2800mm is not going to be easy. I am very satisfied with the star images. They are as advertised, crisp and round throughout the field and no flattener is required. OK so I guess you can get what you pay for sometimes!
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There is a place on Earth I call “Astronomyland”. Kind of like Disneyland for astronomers. Dark pristine sky, peaceful, where observatories dot the landscape. In the early 2000’s a group of astronomers and land developers searched the country for a place to set up “remote” observatories. Amateur equipment and software had evolved to where no longer were you stuck in a bad light polluted part of the world but you could have the opportunity to observe in a dark site and you didn’t even have to be there! Probably the first or one of the first Astronomylands was Mayhill, NM. The place was called “New Mexico Skies”. The sister development across the street was named “Stars End”. Now I knew about this place for years living back east. I would go every year to the NEAF show (Northeast Astronomy Forum) and every year I would go by the “New Mexico Skies” booth and dream about it. I would go home, tell my wife “one day, some day”. Little did I know I would actually wind up here with a permanent place. As luck would have it the job in Western Mass after 20 years was not going to last and we had to move. We decided to move to a place we would want to stay. A job listing came up for Las Cruces NM, less than 2 hours away from New Mexico Skies. I said we had to check that out! The rest was..sorry for the cliche…history. If you would have told me 10 years ago that I would be going from this:
I would have thought that was impossible. But I suppose God has a way of manifesting sometimes in unexpected ways. So here we are in Astronomyland! I swear I really do have to pinch myself sometimes to make sure it’s real!
When I am not working the weekend, my wife and I are up here and we take a morning walk through the Stars End neighborhood where we have our place. What an amazing place this is! Sure, since this development was started there are several “Astronomylands” that have popped up but this one is still special. Still a Bortle 2 sky with no sign of degrading. Very interesting folks have settled here from all different backgrounds, some teachers, some retired NASA scientists, software developers and engineers, retired physicians etc. All with like minded interest, ..a dark night sky!
So I invite you to take a walk with us through our wonderful neighborhood to see some of the sights along the way:
Well I hope you enjoyed our walk through our wonderful neighborhood! For more on the history and construction of Orion’s Belt Remote Observatory you can visit my website orionsbeltobservatory.com
Thanks for reading!
Now with the eclipse excitement settling down it’s time to return to the night time world! Back at Orion’s Belt for the holiday weekend we have arrived at a critical point in the installation process for the newly acquired 16″ telescope. Time for optical testing which means we have to take an image! I guess technically it’s sort of a first light but I don’t really count it as such because it’s just star testing. However it is kind of a big deal because if we take this image and the stars are totally jacked up either we have to start collimation from scratch which means we have to buy more collimating equipment or in the worst case scenario there is an optical problem which needs repair! After all the scope is shipped from overseas. Who knows what could have happened. There is also the issue of focus, if it can be reached at a point somewhere in the middle of the focuser travel so we can do automated focusing. There are no “spacers” with this system. We had to get the right adaptor with just the right amount of backfocus. Hopefully we did the math right!
To get to this point it took the last 2 months slogging through the installation of the accessory equipment on the scope: the focuser, control system etc. You can see the blow by blow narrative in this page. I think overall it really went fine. Yes there were some issues but with this kind of stuff how can there not be? Mostly I was very anxious and apprehensive due to the huge expense of this equipment, every step of the way worrying about something breaking or malfunctioning. But thankfully no disasters yet and I got through it and learned a bunch in the process!
Looks more like a NASA space probe than a telescope, but then again we are able to “travel” to the far reaches of the Universe with it!
So now the first ever image taken with the RiDK 16″:
What we see are defocused star images but still pretty round all the way from side to side. Yay! We probably don’t have to send it back! The 2 lines in the image are called “column defects” and are present in the ccd sensor. These do occur with the standard “class 2” ccd sensors (class 1 sensors with no defects are generally used for research). The column defects do process out pretty easily with dark frames
Next we rack out the focuser to close to focus position and see it does lie somewhere in the middle of the focus travel.
Conclusion so far anyway is that 1) We are close to decent collimation and 2) We can reach focus pretty easily with room in front and behind. That is a huge relief! Now onward and upward!
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The Trifid nebula, whose name means “divided in 3 lobes” is an amateur favorite. An island of HII region which is the red portion (HII regions are emission nebulae created when young, massive stars ionise nearby hydrogen gas clouds with high-energy UV radiation causing the gas to emit red light) , a blue “reflection “portion which occurs when light of the nearby massive blue stars reflects off of the dust, and a “dark nebula” portion which divides the nebula into its 3 lobes. There is also an open cluster of stars in the field. The Trifid is 5000 light years away toward the center of out galaxy, hence the very dense surrounding star fields and dust.
I completed my test of the Tak FS120 imaging capability and you can see the result below. I was pretty happy with it, especially considering the very modest set up I am using (see last entry) . For the full resolution image you can click on the thumbnail on the right side of the blog under “my astroimages”. I am looking forward to more projects with it!
Until next time. Thanks for reading!