Deep-Sky Observing And Other

Depending on the device you are using, it may be necessary to slide the chart to the right to see in its entirety.

Number Code

Map Color Code

Label

Sky Mag.

Naked Eye Limit Mag.

320mm Limit Mag.

M33 visible?

M31 visible?

Central Galaxy visible?

Zodiacal light visible?

Light Pollution

Clouds

Ground Objects

1

excellent dark sky

22.00–21.99

≥ 7.5

> 17

obvious

.

casts shadows

striking

airglow apparent

.

visible only as silhouettes

2

average dark sky

21.99–21.89

7.0–7.49

16.5

easy with direct vision

.

appears highly structured

bright, faint yellow color

airglow faint

dark everywhere

large near objects vague

3

rural sky

21.89–21.69

6.5–6.99

16.0

easy with averted vision

.

complex structure

obvious

LP on horizon

dark overhead

large distant objects vague

4

rural/suburban transition

21.69–20.49

6.0–6.49

15.5

difficult with averted vision

obvious

only large structures

halfway to zenith

low LP

lit in distance

distant large objects distinct

5

suburban

20.49–19.50

5.5–5.99

14.5–15.0

.

easy with direct vision

washed out

faint

encircling LP

brighter than sky

6

bright suburban

19.50–18.94

5.0–5.49

14.0–14.5

.

easy with averted vision

visible only near zenith

.

LP to 35°

fairly bright

small close objects distinct

7

suburban/urban transition

18.94–18.38

4.5–4.99

14.0

.

difficult with averted vision

invisible

.

LP to zenith

brilliantly lit

.

8

city sky

< 18.38

4.0–4.49

13

.

.

.

.

bright to 35°

.

headlines legible

9

inner city sky

.

≤ 4.0

.

.

.

.

bright at zenith

.

.

My view to the east (last night @ 9:15 PM, November 18, 2023 from my back deck) showing the light pollution at about 15º above the treetops.

I always try to observe deep-sky objects at least one hour or two from the meridian.

It is difficult to see the Pleiades “visually” at this low altitude. I was using an iPhone 14 “handheld” to make a photo for illustrative purposes.

The Pleiades was my first deep-sky object when I was 12 years old. I remember so well, walking out in my front yard in about mid-November and seeing this cluster rising above the treetops.

At that time, I had no clue as to what this group of stars were.

A year or so later I found out it was the Pleiades, M45 and my interest in amateur astronomy began, which continues to this day. Interesting to note: This was Leslie Peltier’s first deep-sky object also, as probably so many others.

The following photo:

Andromeda is difficult for me visually, and requires averted vision. At the meridian, it can be fairly easy, but averted vision still works best.

The following photo using my phone, presents the galaxy quite a bit brighter than naked-eye.

So, I estimate the Bortle Scale from my backyard to be ~6.5. I think we can all agree, the Bortle scale is not a definitive number, but using this criteria can describe an observing site pretty accurately. I’d say John Bortle developed an excellent, simple and objective measurement system for judging different observing sites, and for comparison with others.

I continue to ride, but “absolutely certain” I’ll not be able to ride another 100,000 miles. My rides in recent years are quite a bit shorter and much slower, but more fun.

Date: October 9th 2023:

I’ve went from an 80mm f/5 refractor to this 10-inch Newtonian in just a matter of days. So, I’m proud of the progress I’ve make, from never using a camera with a telescope, to “at least” an image of the moon. And all within a week!

I changed some settings on my camera, something I’d never done before. It had been set on ISO 100, for my everyday snapshots, and changed to ISO 400 this morning for this moon shot. I was amazed how much brighter the moon was when focusing through the camera using this 10-inch versus the 80mm refractor.

For sure a lot easier to focus with the brighter view due to the size of the telescope.

The field using this telescope is really narrow and small as this photo shows. Now I’ve got to figure out how to set the “exposure time” for some small and bright deep-sky objects.

I’m actually amazed that I could do this...and hopefully more and better to come. Debbie

Telescope: 80mm: 400mm Focal Length: f/5

Camera: Nikon D3300

Nikon T-Adaptor

Camera Setting: Manual

Vixen GP Equatorial Mount

The following photo was made after sunrise

Nikon T-Adaptor

I also made a photo as following using a 10-inch f/4.5 EQ telescope. Roger had using this telescope during an early morning 4:00 AM observing session of a galaxy. So, before bringing it back into the house, he suggested I try a moon photo with this telescope. This is my photo.

The following solar project was suggested by Tom English:

Place a straight pole into the ground, facing due south, and at an angle of 55 degrees:

Then on the two equinoxes (the first day of spring, and the first day of fall) the sun will cast no shadow, as the sun will be shining directly down the steel rod.

Note: Tom was formerly an astronomy and physics professor at Gardner-Webb University for many years, but now teaches in Greensboro. However, we still stay in touch.

During more than a decade, we spent many nights in my backyard with telescopes, enjoying observing galaxies, nebulae and star clusters. Tom would often bring an 8-inch Celestron Orange-Tube SC telescope, and we’d compare views with my 10-inch Newtonian.

The Celestron Story: https://rogerivester.com/2022/09/26/the-8-inch-orange-tube-schmidt-cassegrain-f-10-telescope-founder-tom-johnson-and-other/ 

So, on June 21st, 2023 (Summer Solstice) the shadow will cast its greatest extent southward, and on the Winter Solstice (December 22nd 2023) the shadow will cast its greatest extent northward on the stick.

My latitude in North Carolina: The Latitude is 35º 15 mins

So a simple calculation to determine the angle of the rod.

(90º – 35º) = 55º

Debbie using an angle finder to determine 55º.

The angle of the rod is toward the South at 55º. So draw a line, with the post, going South to North.

Note the shadow: It will be increasing, each day, and getting shorter, until September 23rd, when there will be no shadow, as the sun will be “pointing directly down” the rod.

At 1:00 PM EDT, today (September 22nd) a photo was made, and indeed showing no shadow, as the sun was shining directly down the steel rod. September 22nd or 23rd…close enough.

The following photo:

The yellow mark indicated the sun shadow on August 24th, and the position of the sun shadows on different days following.

The red mark was made on October 4th.

The black mark was made on October 13th 2023. Note the rapid movement of the sun heading south in less than two weeks!

Note: The crossbar on the rod is for pushing in the ground with my foot, and nothing more.

Cocoon Nebula in Cygnus: Very faint and difficult, but with patience and a “reasonably” dark-sky it’s possible. Look for the tiny star chain, just to the NE and you know, you’re close to the Cocoon.

Comet Hale-Bopp With All Three Tails Being Sketched: The Gas Tail, The Dust Tail and The Anti-Tail. Charcoal sketch on black card stock. (March 1997)

10-inch EQ f/4.5 Newtonian Telescope: Nine Galaxies in a 1/2º Field-of-View, when centered on M86

Veil Nebula West

Veil Nebula East

I’ve been having to reset the time or clock on my Celestron CGE-Pro equatorial mount before observing. I just recently found out from others, there is a CR2025 battery that requires changing from time to time.

Celestron calls for a CR2025 as a replacement battery.

Re: Replacing the internal battery in a Celestron CGE-Pro Equartorial Mount from Celestron online, as following:

The battery is located under a clip on the PC > Autoguide > Power Cord board inside the pier. Replace with a 3-volt CR2025, available at many drug, photo, and hardware stores.

It’s actually a fairly straight forward process, but “can be” time consuming.

There are a lot of electronics surrounding this battery…so you don’t want to damage your mount electronics due to an inexpensive leaking battery.

The bolts that hold this top cap are Allen heads requiring a 5.5 mm wrench. Seldom do I find any application, involving telescopes, high-end precision bicycles or other that require half sizes, but this is no problem.

The following plate was a bit difficult to remove. It was “stuck” and required attempting with several techniques before finally getting it out. It had drops of silicon in several places along the edge, which had to be removed and cleared before removing the aluminum plate.

I found that using Allen wrenches “to hook under the two larger holes” in conjunction, and then pulling up was successful.

Use care as not to damage the plate, or some of the ribbon wires, located just underneath the plate.

When installing the new battery, I used “nitrile powder-free gloves” to avoid getting finger oil or grease on the battery.

Remove the old battery, insert the new one, and then reassemble the mount, connect the Dec and RA cables and you’re all finished.

However, everything related to time and dates will have to be changed via the hand controller.

Storage:

I had set the clock, and checked all other specifications during this afternoon. However, last night when performing the alignment process, the mount couldn’t even find Vega, just overhead. And could not perform any two or three star alignment.

So finally, after at least an hour of frustration…I did a “complete factory reset” and reentered all necessary information which resolved the problem.

Note: After the battery change, the time is perfect, each and every time.

The story how a very small mountain town in western North Carolina became very important to the world of professional astronomy, with it’s contribution to the making of the first 200-inch Palomar Telescope Mirror. And most importantly, as of current all electronic devices use chips made from the ultra-pure quartz from Spruce Pine. Roger Ivester

I’m posting the following “brief excerpt” from a published article by David Biddix of Spruce Pine:

Description: Spruce Pine, North Carolina, a small town in the western part of the state, has a storied history related to astronomy instruments. The Spruce Pine Mining District, a geographical area that features significant deposits of mica, feldspar, and quartz, has played a significant role in astronomy for the past 80 years. The mirror in the 200 inch Hale Telescope at Palomar Mountain is made from quartz mined in the District in the 1930s. Today, all electronic devices including computers, televisions, cell phones, mp3 players, and other gadgets owe their existence to ultra-pure quartz mined near Spruce Pine. In this podcast, you’ll learn how this down-to-earth small town helps astronomers reach for the stars.

Bios: David Biddix is a local historian who has published two books in Arcadia Publishing’s Images of America series with co-author Chris Hollifield: one on Spruce Pine, North Carolina and one on Little Switzerland, North Carolina. He was born and currently lives in Spruce Pine. David’s interests include amateur radio, astronomy, and history.

Alex Glover…is the Director of Mining and Environment for Active Minerals International, LLC. He is a licensed professional geologist in nine southeastern states in the United States and has lived in the Spruce Pine area since 1997. He is interested both in the geology of the Spruce Pine Mining District and in its history, which goes back some 170 years.

….I’ve always wondered why ore from the Chestnut Flats Mine near Spruce Pine was chosen for the telescope’s mirror. Recently, I had a discussion with Alex Glover, a local geologist and mining historian who is very familiar with what is known as the Spruce Pine Mining District, a 10 mile-long, 5 mile-wide outcropping of rock from early in earth’s history that contains some of the purest minerals in the world and is the economic lifeblood of this region. This purity was the reason Corning Glass came to this region to find materials for the mirror. Alex speaks about what types of minerals are found in the district….

David Biddix: Spruce Pine, North Carolina

Note: The following photo of the (Chestnut Flats Mine) where the quartz for the 200-inch Palomar mirror was mined, is now closed and privately owned.  Roger Ivester

My personal quartz specimens as following from the Spruce Pine mining district:

Historic photo of the mine from days past. Photo credit: Mitchell County Historical Society