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NGC 3226 and NGC 3227, Galaxies in Leo: April 2021 Observer’s Challenge Report #147

April 16, 2021

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

April 2021

Report #147

NGC 3226 & NGC 3227, Galaxies in Leo

Sharing Observations and Bringing Amateur Astronomers Together

Introduction

The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It’s open to everyone who’s interested, and if you’re able to contribute notes and/or drawings, we’ll be happy to include them in our monthly summary. Visual astronomy depends on what’s seen through the eyepiece. Not only does it satisfy an innate curiosity, but it allows the visual observer to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what astronomers saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings, and that’s the tradition we’re stressing in the Observer’s Challenge. And for folks with an interest in astrophotography, your digital images and notes are just as welcome. The hope is that you’ll read through these reports and become inspired to take more time at the eyepiece, study each object, and look for those subtle details that you might never have noticed before.

This month’s target

William Herschel discovered this interacting galaxy pair on 15 February 1784 with his 18.7-inch speculum-metal reflector. His hand-written journal of the discovery reads: “Two nebulae almost close together. Perhaps 1½ or 2′ asunder, they are pretty considerable in size, and of a roundish form; but not cometic; they are very faint.” He also notes that on this night he first used: “A new, large object Speculum. It is very bright but not quite as distinct as my first, I shall however use it all the night.”

Together known as Arp 94, NGC 3226 and NGC 3227 are wedded in a gravitational dance 47.2 ± 0.2 million light-years away from us. Their complex dance has spawned a remarkable array of tidal tails as well as one tidal dwarf galaxy — a gravitationally bound condensation of gas and stars formed during the repeated encounters of the two parent galaxies.

The most recent journal paper on this captivating system can be perused here: https://www.aanda.org/articles/aa/full_html/2021/01/aa38955-20/aa38955-20.html

or click on the PDF button for a more reader-friendly version.

Mario Motta: Observer from Massachusetts

The following image is 2.5 hours of galaxies NGC 3226 and NGC 3227 with a Luminance filter with 1 hour each R,G,B, filters for a total of 5.5 hours of imaging. It was taken with my 32-inch f/6.5 telescope with a ZWO ASI6200 camera, then processed in PixInsight. The distance is 77 Million Light years away. This spiral galaxy is interacting with a dwarf elliptical galaxy, also known as Arp 94. The arp catalog is among my favorite, for unusual objects in the sky.

Glenn Chaple: Observer from Massachusetts

Our April Observer’s Challenge brings us to a cosmic double-header, the interacting galaxies NGC 3226 and NGC 3227. NGC 3227, the brighter of the pair at magnitude 10.3, is a Seyfert galaxy (a spiral galaxy with a quasar-like nucleus). Its partner, the dwarf elliptical galaxy NGC 3226, is about half as large and a magnitude fainter. The two are gravitationally bound and are listed in the Atlas of Peculiar Galaxies as Arp 94.

If you use a scope with GoTo technology, you’ll find these galaxies by plugging in the coordinates Right Ascension 10h23m30.6s and declination +19°51’54”. I suggest you skip the electronics and simply aim your scope at the 2nd magnitude star gamma (γ) Leonis (Algieba). NGC 3226 and NGC 3227 are less than a degree east. Before you go anywhere, however, center this star in the telescopic field and switch to an eyepiece that magnifies around 100x. Algieba is a showpiece binary pair whose components, of magnitudes 2.4 and 3.6, are currently separated by 4.7 arc-seconds. These spectral class K1 and G7 giants shine with striking golden yellow hues.

Once you’ve paid your respects to Algieba, keep your eye glued to the eyepiece as you slowly move eastward past a pair of 9th magnitude stars to the spot marked with an “+” on the accompanying finder chart. At this location, I was able to see a pair of hazy smudges (the nuclei of the two galaxies) separated by about 2 arc-minutes. I was using a 10-inch reflector and a magnifying power of 141x under magnitude 5 skies. There was no sign of the spiral arms of NGC 3227. The appearance of NGC 3226 and NGC 3227 was not unlike a small-scope view of M51 and its companion NGC 5195.

NGC 3226 and NGC 3227 were discovered by William Herschel on February 15, 1784. Their distance isn’t accurately known. The SIMBAD astronomical database cites 5 measurements that range from 51 to 73 million light years.

Uwe Glahn: Observer from Germany

Object: Arp 94(VV 209, KPG 234) = NGC 3226, NGC 3227 

Telescope: 4-inch Bino, 55x

Bedingungen: fst 6m5+

Seeing: III

Ort: Wachstedt

Barry Yomtov: Observer from Massachusetts

As I reported last month my primary optics (RASA 11) had to be set aside because my mount had to go for repair, so I imaged with the C9.25/Hyperstar. Fortunately my mount was repaired and returned with a fairly quick turnaround. I did manage to have a session with the C9.25/Hyperstar, for April’s NGC 3226/3227. I’ve also been lucky to have a clear night to have an additional session with the RASA 11. For April I’ve decided to present a comparison of NGC 3226/3227 between the two optical systems and using the same camera.


RASA 11C9.25/Hyperstar
Aperture (mm)279235
Focal Length (mm)620540
Focal Ratiof/2.22f/2.3
FiltersAstrodon notched light pollution filter, and    UV/IR cut filter (used for galaxy imaging)none
Camera Pixel size (µm)2.4 x 2.42.4 x 2.4
Camera Resolution (pixels)5496 x 36735496 x 3673
Pixel Resolution in seconds (“)0.800.92
Field of View in degrees (°)1.22 x 0.811.4 x 0.93

By comparing the field of view (FOV) and the pixel resolution between the two sets of optics, the RASA 11-inch is about 87% of the 9.25-inch Hyperstar optics. The following figure is a comparison of the field of view between the two sets of optics using NGC3226/3227 as the selected object of interest; (Field of View Calculator, courtesy of Astronomy Tools).

I also compared the distance between two star locations and the ratio was also about 86.4%. The following are the processed images for each optical system.

Using a 9.25-inch SC Hyperstar taken on March 19, 2021: 93 subs, 30 sec exposure, for 47 minutes total exposure time

The 11-inch RASA was able to detect more of the outer periphery as well as greater detail of the core of NGC  3227, compared to the 9.25-inch Hyperstar. The improved quality of the image can be contributed to (1) improved pixel resolution (0.8“ versus 0.92”) (2) 1.42x greater light gathering power with the 11-inch RASA than with the 9.25-inch and (3) the light pollution filter of the RASA reduces background light pollution noise thus improving the signal to noise ratio.

RASA 11-inch taken on April 4, 2021: 97 subs, 35 sec exposure, for 57 minutes total exposure time. 

The RASA was able to detect more of the outer periphery as well as greater detail of the core of NGC 3227, compared to the 9.25-inch Hyperstar. The improved quality of the image can be contributed to (1) improved pixel resolution (0.8“ versus 0.92“) (2) 1.42x greater light gathering power with the 11-inch RASA than with the 9.25-inch and (3) the light pollution filter of the 11-inch RASA reduces background light pollution noise thus improving the signal to noise ratio.

The Southern Cross by Commercial Airlines Pilot: James Yeager

March 29, 2021

Jim Yeager has always allowed me to use any of his aerial photos, which over the years have included, a beautiful photo of the Barringer Crater in New Mexico, covered with snow, and the Mount Potosi Observing Complex in SW Nevada. Both of which I’ve used in previous blog articles and other.

I really like the following image, as I’ve never seen the Southern Cross.

Jim’s notes and photo:

Here is somewhat of clear picture taken with an iPhone using a 3 second exposure on a descent out of 41,000 feet about 100 miles north of Lima, Peru.

You can see Alpha and Beta Centauri pointing to the Southern Cross.

The residual cockpit lights, moonlight behind us, and the haze of high altitude cirrus kept us from seeing the Magellanic Clouds.

Other aerial photos by Jim Yeager:

https://rogerivester.com/category/mount-potosi-observing-complex-in-southern-nevada/

https://rogerivester.com/2016/12/06/aerial-view-of-meteor-crater-compliments-of-james-yeager-pilot-american-airlines/

iOptron CEM70 – Center Balanced Equatorial Mount: By Guest Host: Mario Motta

March 19, 2021

I was considering making a take-apart mount but finally realized I could not build one light enough with all the features I desire, so, I purchased an iOptron CEM70G mount. (guilt for an amateur telescope maker!)” Mario Motta

My story:

Up to this point I have always built my own equipment, such as my 32-inch f/6 reflector telescope in Gloucester, Massachusett, which is my main telescope for imaging, and in a dome attached to my house.

At the end of this year I will be retiring, and per my wife’s wishes will be spending winter months in Naples Florida at our second home. However, in my Florida location I can’t build a dome for a number of reasons. This is due to (hurricanes, building restrictions, etc.)

I was considering making a take apart mount but finally realized I could not build one light enough with all the features I desire, so, I purchased an iOptron CEM70G mount. (guilt for an amateur telescope maker!)

The head weighs only 30 pounds , tripod another 30 pounds, for a manageable weight, yet, tracks very well (3 arc sec error periodic error), is very sturdy, can carry a 70 pound weight load, so it can handle up to a 14-inch scope easily. It has a built-in polar scope alignment guide scope. It even has WiFi, and 4 USB ports. 

Why the center mount instead of a german equatorial or a fork? At 43º North latitude (my 32-inch sits in a handmade fork) or german equatorial which works fine.

Look at the following images as following, “German equatorial”and see that at 43º, the center point of gravity pushes through the main mount, and weight of scope and dec axles pushes down the polar axle, a fork also works the same way.

However…at 26º N latitude, the weight of the scope and counter weight is very far forward, putting all the stress on the forward polar bearing.

Not very stable: A fork overhangs badly.

Now let’s see what a center mount does:

At 43º North latitude, it works well, but all the thrust is on the rear bearing and a german equatorial may be best. Now see what it looks like at 26º N latitude. (see image center mount) Here the weight of the scope is directly over the center of the polar axis, the weight is evenly distributed on both bearings, thus can handle a heavier load with less stress, overall an ingenious design. In reality this is nothing new, what this is… is a miniature English “cross axle mount”.

I built one for a 16-inch scope in the 1980’s and it worked very well.  See the following photo following the M42 image:

In summary, if far north, fork or german equatorials are best, but if closer to the equator, a center mount or cross axle is best.

An Image of my new mount is attached, with a small 6-inch RC for test purposes. My plan is a 12 -14 inch on this mount. The following Image of M42 (test subject, not a long great image, but more of a proof of concept for location and mount. (this image was made unguided).

The English Cross-axle I built in 1985, with my older 16-inch f/4.5 home made telescope.

I’m proud to say: My current 32-inch f/6.5, and every part is hand-made

How to Choose Your Telescope Magnification – Sky and Telescope Magazine: By Al Nagler

March 9, 2021

One of the best articles I’ve ever read concerning the calculation of everything involving telescope eyepieces.

https://skyandtelescope.org/astronomy-equipment/choosing-your-telescopes-magnification/

I was fortunate to meet Al Nagler a few years ago. Such a nice guy….

My Quest to Observe the Entire Herschel Catalog: By “Guest Host Larry McHenry” From Pittsburgh

February 18, 2021

It is Done!

As of May 13th, 2020, I have now completed observing all 2,482 identifiable objects of the Herschel 2500 Catalog.

My last catch was ‘H II-840’ a pretty little one-arm galaxy – NGC3978 in the Great Bear – Ursa Major.

The idea for this ‘Herschel Objects’ project started back at the end of 2012, as I was wrapping up a Constellation survey based on the “Night Sky Observers Handbook“. I realized that my observations would already include a large number of the Herschel-400 objects. So after identifying all the ‘400’ objects that I had previously observed, it only took me less than a year to finish the ‘Herschel 400’ list. For this phase of the project, I utilized the Astronomical League’s “Herschel 400 by Constellation” list and their “Observe the Herschel Objects” booklet. I then downloaded the AL’s “Herschel-II” list of the next 400 objects and began hunting those. 

By the fall of 2016, I was down to the last 60 objects and was wondering what my next project should be. Flipping thru some old “Sky & Telescope” magazines, I ran across an article from the August 2012 issue by Rod Mollise on observing the entire Herschel Catalog of 2500 objects using a deep-sky video camera. This was the inspiration (and project), that I needed, as I was already a videoastronomer, so I began a multi-year effort to observe the entire Herschel Catalog.

So today, we’ll discuss what I’ve learned during that journey among the Herschel Objects. Hopefully, when we are done, you will find them as interesting to hunt as I do.

First, a little background on the Herschel’s:

After the Messier List, the Herschel Object’s are the next most observed deep-sky objects. 
Most amateur astronomers know them by their NGC numbers, but they started out as a list created by British amateur astronomer William Herschel and his sister Caroline, two of the greatest astronomers from the ‘Age of Enlightenment’, which marked the birth of modern science.  

From 1782 to 1790, the Herschel’s conducted systematic surveys of the night sky, in search of “deep sky” objects, and discovered over 2500. Herschel used two telescopes for his survey, a “20-foot Reflector”, which had an 18.5” speculum-metal mirror, and later the great “40-foot Reflector” with a 48” mirror.  Most of Herschel’s recorded observations were made using the ’20-foot’ telescope, as the larger ’40-foot’ was cumbersome to use and suffered from tube current distortions.

Herschel’s telescopes didn’t have clock drives to track the stars, so instead, he would point the telescope to the meridian and let the Earth’s rotation carry objects across his field of view while he was up on a ladder observing. William would then call down to Caroline, at the bottom of the telescope, whenever he saw anything interesting, and she would write down his descriptions and time and where the telescope was pointing. Caroline would then quickly read this back to William and he would confirm the observation while the object was still in the eyepiece. This method allowed them to observe and record a nightly east-west strip of sky. The next day, the two of them would use their recorded observation to calculate the objects position on a star atlas. They would then move the telescope’s elevation up or down, in preparation of the next nights survey run.  Using this method, they were eventually able to observe all of the sky visible from England.

The Herschel’s observing technique of surveying, cataloguing, and classifying what they found, and then using that data to try and understand the structure of the universe, has become one of the most important tools of modern astronomy.

How I accomplished the project:

So back in 2016, as I began a multi-year effort to observe the entire Herschel 2500 Catalog, the first thing I needed to do was come up with a list of the Herschel Objects! While during the process of William and Caroline Herschel’s original recording and publishing of their observations from 1786 thru 1802, along with subsequent reprints and revisions over the 19th century, there have been a number of discrepancies over misidentified or non-existent objects. Depending on the source, of the Herschel’s 2500 objects cataloged, there are anywhere from the low 2400’s to over 2500 actual objects. Mark Bratton, in his book “The Complete Guide to the Herschel Objects“, gives a good review of the issues and historical attempts to rectify Herschel’s list of objects. He eventually settles on there being only 2,435 identifiable Herschel Objects. (I utilize his book’s visual descriptions and DSS images to help in comparing and confirming my personal observations). In addition to the above book, I also utilized George Kepple & Glen Sanner’s “Night Sky Observers Guide Handbook” and internet resources ‘WIKISKY‘ and ‘The NGC/IC Project’ to validate my observations. 

To help tackle this project, I downloaded several lists from various websites, and after combining, distilling, and sorting, I generated a personal spreadsheet/logbook to help in my tracking & logging. The core data for my logbook comes from a list of 2,482 Herschel Objects by Steve Gottlieb. 


All of my Herschel Object observations can be found in their individual constellations in my website under my ‘Constellation Tour’ page. To see the entire list together, I’ve created a specific page for the Herschel Project: “Herschel Tour”  

http://www.stellar-journeys.org/herschel-tour.htm


Over the course of this project, I have spent a total of 239 nights working my way thru observing all of the Herschel Objects. 

Even though I really didn’t get serious about completing the list until 2012, my observations stretch all the way back to 1984. 

All of the early observations are visual sketches, (78 objects), made at the telescope eyepiece, with everything after 2001 using videoastronomy (EAA) short-exposure lucky imaging technique. I eventually used a total of ten different telescopes for this project. Six visually – 80mm f3.2 refractor, 8″ f4.5 dob, 10″ f5.6 dob, 13.1″ f4.5 dob, and a 8″ & 12″ SCT at f10. The dobs and small refractor were manual telescopes, with the two SCT’s being motorized, but all required using star-charts and star-hopping techniques to locate the objects. 

For the videoastronomy observations, I used four telescopes – 50mm f3 refractor, 80mm f6 refractor, 6″ RC at f9, f6.3 & f5, and a 8″ SCT at f10, f6.3 & f3.3.  All these telescopes were on either SCT or CGEM mounts that could track and later utilize GOTO.

The cameras used were a StellaCam-EX (2.5 seconds exposure), StellaCam-II (8 seconds exp), a Samsung SDC435 (8 seconds exp), a peltier cooled, wireless controlled StellaCam-3 (unlimited exp), and finally a ZWO ASI294MC Pro camera used in EAA mode (generally for around 120 second exposure). 

While I prefer going to dark sky locations, such as Pennsylvania’s Cherry Springs State Park, for my observing, utilizing near-realtime deep-sky videoastronomy cameras has allowed me to pull in faint 14th magnitude plus galaxies not visually possible from my backyard observatory located within 10 miles of downtown Pittsburgh, PA. This greatly expanded the number of clear evenings available for working on this project. 

Having spent time over the past several years following in the Herschel’s tracks, you could begin to pick-up on how they were doing their observing run for that particular night back in the 1780’s, slowly letting the Earth’s rotation bring each object into their sweep. Using today’s modern equipment, there’s no need to wait; all you had to do was hop down the sweep path to the next observable object. When you think about that, it’s sort of inspiring to think that in your own way you are following in their footsteps!

In retrospect, I have learned a lot about the lives of William and Caroline Herschel, along with the objects that they discovered. While there are a number of nice large, bright objects including galaxies, star clusters, and nebula, the majority of Herschel’s objects are small, faint, dim smudges of galaxies. It gives you an appreciation for the brighter Messier Objects. Still, there is a wide variety of shapes and sizes of interesting deep sky objects for any type of telescope. I now have a much greater respect for all those faint fuzzies and the work of the Herschel’s! So I encourage everyone to get out tonight and try your hand at finding and observing the deep-sky objects of William and Caroline Herschel!!

An examples of my many sketches:

My equipment used for this project: Telescopes, observatory and camper : Larry McHenry, Pittsburgh, Pa


Hope you enjoyed my story: Larry McHenry

Herschel 400 Notes: By “Guest Host Sue French” From New York

February 16, 2021

Sue and Alan French

Click on to enlarge: The latest Herschel 400 book (above) from the Astronomical League. Consider ordering your copy today.

Star Trails Image: By Guest Hosts: Babak Tafreshi (Photographer) and Mario Motta

December 2, 2020

Star Trails image at the residence of amateur astronomer Mario Motta, by renowned photographer, Babak Tafreshi.

Click on image to enlarge:

Babak Tafreshi is an award winning photographer working with the National Geographic, a master of night-time photography and nightscape videos. He used the context of night sky to bridge Earth and sky, art and science, cultures and time. He is also a science journalist and the founder of The World at Night (TWAN) program; an elite group of about 40 photographers in 25 countries who present images to reconnect people with importance and beauties of the night sky and natural nights (since 2007).

Born in 1978 in Tehran he is based in Boston, United States, but could be anywhere on the planet, chasing stories from the Sahara to the Himalayas or Antarctica. He is also a contributor to Sky&Telescope magazine, the European Southern Observatory (ESO), and a board member of Astronomers Without Borders organization, an international organization to bridge between cultures and connect people around the world through their common interest to astronomy. He received the 2009 Lennart Nilsson Award, the world’s most recognized award for scientific photography, for his global contribution to night sky photography.

As a science journalist he has contributed to many television and radio programs on astronomy and space exploration specially when living in Iran. He was the editor of the Persian astronomy magazine (Nojum) for a decade and been involved with various science education and outreach programs.

Babak started photography of the night sky above natural landscapes and historic architecture in early 1990s when he was a teenager. He has always been fascinated by the universality of the night sky; the same sky appearing above different landmarks of the world. Photography, science stories, and eclipse chasing has taken him to the 7 continents.

My Ultimate Image Of The Horsehead Nebula: By Guest Host, Mario Motta

November 24, 2020

I did a 4 hour exposure (32-inch telescope) of the horsehead using 6 filters. Ten days I ago spent 4 hours obtaining a new horsehead nebula. This is using 6 filters, red, green, blue, but also Ha, S2 and O3. Using narrowband is tricky for color balance but using the RGB helped that out, and got the intrinsic resolution enhancement of the narrow band filters. Been busy, so finally processed this weekend. My previous image was eight years ago only RGB. There is significantly more detail in this image than my prior. I had to play with the six different filter stack sets to get just the right balance of detail and color.

If anyone wants to see my collection of over 600 images, broken into messier, NGC, IC, etc, go to: www.mariomottamd.com

Thank you, Mario Motta

Reiland 1: Obscure Cluster Plus Nebula in Cepheus

October 18, 2020

Earlier this year (Spring 2020) I was communicating with Tom Reiland of Pennsylvania. Tom was recently a recipient of the Astronomical League, Leslie Peltier award, and a lifelong amateur. He mentioned to me about a cluster in Cepheus which he discovered back in the 80’s, and was given the name, Reiland 1.

Right Ascension: 23h 04m.8″ Declination: +60º 05

The following image provided by Mario Motta from Massachusetts: 32-inch Reflector; 40 mins asi6200 camera

The following images Provided by James Dire of Illinois: 8-inch f/8 Ritchey-Chretien telescope with a 0.8x FR/FF and a SBIG ST-2000XCM camera. Exposure 60 minutes

An excellent report by Mike McCabe from Massachusetts: Click on the above link.

October 2020 New Moon In Jordan by Anas Sawallha: 19 Hours 36 Minutes

October 18, 2020

I was happy to have received an email (September 17th) from my astronomy friend in Jordan, Ana Sawallha with this 19 hour 36 minute new moon photo. Thank you Anas.