M41- Open Cluster in Canis Major-February 2018 Observer’s Challenge Report #108

Posted March 9, 2018 by rogerivester
Categories: Observer's Challenge Reports

FEBRUARY 2018 OBSERVERS CHALLENGE – M-041

Pencil sketch:  6-inch reflector @ 46x and 1.3º field of view: 

M41 Adjusted

Inverted colors

Rogers M-041 Inverted

Messier 41 (NGC 2287) at magnitude 4.5 is visible without optical aid. I often enjoy viewing this cluster with a pair of 7 x 21 mini-binoculars. It is easily located at about 4º south of Sirius, and NW of 6.0 magnitude 12 Canis Majoris.

A beautiful, but sparse cluster, very irregular shape, with several small chains of stars. The most noticeable star chains are on the SW and NE.

When using a 6-inch reflector, I can count ~60-70 stars. A small circlet of stars envelope the central region of the cluster. M41 contains the famous red star, known as the Espin star (HD 49091) magnitude of 6.9 and a K3 spectrum. The star was named after Rev. T.E. Espin (1858-1934.) I normally see this star as a deep-orange in color.    Roger Ivester

 

M41 image by James Dire:  

102mm (4-inch) f/7.9 refractor using a 0.8X focal reducer field flattener with an SBIG ST-2000XCM CCD camera. The exposure was 30 minutes. North is up, and east to the left.

M41

M41 is a beautiful galactic star cluster located 4° south of the bright star Sirius. The cluster can be seen naked eye from a dark site. It’s mag. 4.5 and is 39 arcminutes in diameter. It lies 2,350 light-years away

Aristotle noted M41 in 325BC as being a cloudy patch in the sky. The cluster was first cataloged by the Italian astronomer Giovanni Batista Hodierna in 1654, and then John Flamsteed in 1702. Charles Messier added it to his catalog in 1765.

M41 has about 100 stars. The brightest is a mag. 6.9 red giant star near the apparent center of the cluster, cataloged as HD49091. This K3 star has the brightness of 700 suns. The cluster is estimated to be 190 to 240 million years old and has a chemical composition similar to the sun.

The brightest star in the image is near the bottom edge, left of center. That star is 12 Canis Majoris, or HK Canis Majoris. HK is a mag. 6 blue giant star with a surface temperature of 18,000K. HK is only half the distance of M41 and thus is not a member of the cluster. The next brightest star in the image is the red giant HD49091, the red giant star near the center of the cluster.   James Dire 

 

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International Dark-Sky Association (IDA) Fully Shielded Home Lighting. Sold by Lowe’s Home Improvement

Posted February 22, 2018 by rogerivester
Categories: Roger's Articles

My first fully shielded house light, with one more to go.  I purchased this one at Lowe’s on Sunday, and put it up today.  Threw away the old standard brass coach light which  spewed light in your eyes when coming in the front door.  You can actually see the house much better when driving up the street.  All the light shines down in a nice concentrated beam.  I need one more for my back door.  The fixture is well made and was very simple to install….

 
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Edmund Scientific of Years Past

Posted February 21, 2018 by rogerivester
Categories: Roger's Articles

Edmund Scientific was the company that spawned my interest in amateur astronomy. From the following books to my first serious telescope, an Edmund 4.25-inch EQ reflector. A Palomar Jr.

It’s really too bad that books like the ones pictured below are no longer available. It was the “Edmund Sky Guide” that taught me all about Sirius and the companion. However, it would be almost forty years later, before I would finally see the companion.  It was worth the wait.  

It was the mid to late 60’s thru the 70s that were what I call the golden years of amateur astronomy. The days when 6-inch reflectors ruled the day (or night) and fortunate indeed was the amateur that owned an Edmund Scientific or Criterion 6-inch f/8 EQ reflector.

The days when the solitary observer spent many nights in their backyard. The days when every amateur wanted to see all of the Messier objects.  As a young enthusiastic amateur, the thought of seeing all of these showpiece objects didn’t seem possible. 

The wonders and excitement of being young:

Being really young, always feeling great, no responsibilities, dreaming of a better telescope, or another Kellner eyepiece.

Now what more could anyone ask for…..

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Planetary Nebula IC 418 in Lepus: February 2019 Observer’s Challenge Object.

Posted February 14, 2018 by rogerivester
Categories: Observer's Challenge Reports

Planetary Nebula IC 418, Lepus, magnitudes; nebula 9.3; central star 10.3

IC 418, also known as Spirograph Nebula.  The name derives from the intricate pattern of the nebula, which resembles a pattern which can be created using the Spirograph, a toy that produces geometric patterns (specifically, hypotrochoids and epitrochoids) on paper.  Source “wikipedia”

The following image:  Hubble Space Telescope

Spirograph_Nebula_-_Hubble_1999

I had a telephone conversation with Glenn Chaple yesterday.  Glenn mentioned PN IC 418 as a potential object for the 2019 observer’s challenge report. This planetary had been suggested by Joseph Rothchild at the most recent meeting of the (ATMoB) Amateur Telescope Makers of Boston. Richard Nugent also of Massachusetts sent me an email, saying he had recently observed this very interesting planetary, using a 20-inch reflector.  

It was only after checking my notes “this morning” (February 14th 2018) did I realize I had also observed this planetary…..25 years ago on (February 14th 1993) which is very coincidental.  

My notes (verbatim) from February 14th 1993:  

10-inch reflector: ” Looks like a blurred star. I would focus on stars outside the telescope field and then sweep back. The nebula was very apparent and obvious when using this method. Nebula fairly bright, mostly round and featureless.  Bluish in color and very small.  No nebula filter was used.”     

Skiff & Luginbuhl:  “This planetary is clearly visible in a 6 cm, appearing as an undistinguished mag. 9 star.  In 15 cm the central star becomes visible, while 25 cm shows it clearly at 200 x.  The surrounding nebula has a high surface brightness, making a poor contrast for the central star.”

This will be the February 2019 observer’s challenge object.   RI 
 

Visual Observing with a 6-inch f/6 Imaging Reflector Telescope: Is Sirius B possible With This Scope?

Posted February 10, 2018 by rogerivester
Categories: Roger's Articles

 

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The above photos of my now “prized” telescope.  I’m sure this scope is going to see a lot of use this year, and beyond.    

One of my desires has always been to bring back the excitement of the glory days of amateur astronomy, when all kids wanted a telescope.  The nights of the solitary observer in the backyard, attempting to locate and observe several of the showpiece Messier objects.

Those were the days for sure.  I wish it were possible to go back.  However, each and every night when I’m out in my backyard with my telescope….I become 13 years old again.  What a great feeling!

Now sharing my excitement from last night in North Carolina:  February 8th 2018

Yesterday, I received an email from observer’s challenge contributor, and email communications friend, Mike McCabe from Massachusetts.  He was very excited as he was finally able to see the companion to Sirius, known as Sirius B or “the pup.”

Mike was using an 8-inch reflector.  His excitement reminded me of my own several years ago when I was able (after ~40 years) to finally see “the pup” using a 102 mm f/9.8 refractor.  

Mike’s success in seeing Sirius B, caused me to want to know if it would be possible to achieve the same using my 6-inch f/6 (OTA) imaging reflector.  

Due to working with my other telescopes, I’ve just not been able to spent much time with this scope.

Last night I made my attempt (February 8th 2018) with the 6-inch to see if the companion to Sirius would be possible with this telescope.   The weather was perfect, 35º and totally calm. When I took my first look at Sirius, I knew that seeing was very good.

I started with 150x, but to no avail and worked my way up to 232x, and there it was, but was unable to hold it constantly.  After more than 30 minutes with Sirius, I decided to attempt another challenge.

I then moved to the Trapezium in the center of the Orion Nebula. Starting with 232x, I was amazed how easy it was to see the E and F stars. There were beautiful airy disc surrounding the primary four Trapezium stars.  The beauty of a multiple or double star doesn’t get any better than this!

When I purchased the 6-inch f/6 imaging reflector, I had no idea of the quality, either mechanically or optically.

However, I found out pretty fast, as star diffraction rings were “almost” identical when defocusing a star, in and out of focus.  After selling my Criterion RV-6, almost 40 years ago, I just wanted another 6-inch reflector, but not an f/8.

The humble optical tube assembly:  TPO brand, made in Taiwan, purchased from OPT in California, 2-inch focuser and also included tube rings.

The cost of the OTA was very good also.  I don’t remember my old Criterion RV-6 being anywhere near this good, optically or mechanically.

I added an 8 x 50 finder, as it came with a tiny 6 x 30.  Not relative to the telescope, but I had to purchase another Vixen counter weight for my 20 year old GP mount. 

My primary reason for purchasing this scope was for portability and ease of carrying and set-up.  My 10-inch EQ reflector seems to get heavier with the passing of each and every year.

I never really expected such a quality 6-inch OTA for such an extremely low price.  Roger Ivester

NGC 1624 – Cluster (+) Nebula Perseus – January 2018 – Observer’s Challenge Report

Posted January 12, 2018 by rogerivester
Categories: Observer's Challenge Reports

Complete Observer’s Challenge Report:  Click on the following link.

JANUARY 2018 OBSERVERS CHALLENGE – NGC-1624

Pencil sketch using a 5 x 8 note card with the colors inverted:  10-inch reflector at 200x.  Roger Ivester

Rogers NGC-1624 Inverted

Image by James Dire from Hawaii

NGC1624

Image by Mario Motta from Massachusetts using a 32-inch telescope

NGC1624

NGC 925 – Galaxy – Triangulum December 2017 Observer’s Challenge Report #106

Posted January 11, 2018 by rogerivester
Categories: Observer's Challenge Reports

Click on the following link for the complete Las Vegas Astronomical Society, Observer’s Challenge report: 

DECEMBER 2017 OBSERVERS CHALLENGE – NGC-0925

Pencil Sketch:

Rogers NGC-0925 Inverted

Photo by Mario Motta from Massachusetts:  32-inch telescope 

NGC925