Saturn in July 2017

July 16th, 2017, 11:10 p.m. local time

All the recent rain and generally miserable humid summer weather almost made me forget that there was a brief pocket of pleasant evening clearness just this past Sunday.  It was a great opportunity to move my 10″ Dobsonian to my back deck for taking in the evening’s astronomical wonders.

I started with imaging Saturn, my primary objective.  I had great difficulty locating Saturn that night and it was almost 20 minutes before I locked on.  Keep in mind this is all a manual process.  My homemade Dobsonian is a Newtonian reflector on a simple alt-az swivel mount.  Even by turning my exposures all the way up, I still had problems finding it.  The lesson here is that it may be next to impossible to attempt imagining of Uranus in a few months with my meager equipment.

Returning to the present though with Saturn, I think this may be my best yet.  When I image the planets, I always take a few sets of videos with different refocusing.  It is really, really hard to get the exact focus right, and the digital camera’s view screen can only get you approximately there, hence the need to take a few sets so that hopefully at least one of them is good.

This night, I took two sets, and it was the first group of videos that allowed me to create the above image.  I also used my Neodymium filter, which I prefer for Saturn as it brings out a nice color contrast among planet’s cloud bands and ring levels.

After my Saturn session was complete, I put a 17mm eyepiece on the scope just to look around on that clear no-Moon night.  Of note was the Hercules Globular Cluster (Messier 13) which I saw clearer than I ever had.  Wow!  I could make out many bright stars in the foreground of the cluster.  I don’t have the proper equipment to image it, but I hope to have the skills to properly draw it by next year.

Also of note was that I am starting to see Cassiopeia earlier and earlier in the Northeast.  It’s the great pointer to the Andromeda Galaxy.  My view to the East is mostly blocked, so I have to wait some before the galaxy is visible via telescope and binoculars from my backyard, but it is comforting to know my favorite gray smudge will be back soon!

Merging the Telescope World with the Real World

From left to right: Moon, Callisto, Io, Europa, Jupiter, Ganymede. Click to see the full-sized image.

As mentioned previously, I took several different types of photographs the night of Sunday, May 7th, when the Moon and Jupiter were close.  One of these perspectives was by mounting my digital camera on a tripod to get a wide-field view of the Moon and Jupiter together.  I took many images with different exposures and ISO settings.  Here is one such raw image:

Click to enlarge.

Here, you see an overexposed Moon along with Jupiter.  This shows the distance between the two at 05/07/2017 21:20 Central Time, approximately.

The important aspect of this picture is that it captures all of Jupiter’s Galilean moons.  If you click on the image, you will easily see three of them – Io, Europa, and Ganymede.  Callisto is there, or at least, is there in the raw TIFF image.  You will have to take my word for it that Callisto is there, just very faint.

How do I know which moons are which?  The easy way I follow is to use this Jupiter moon tracker, plugging in times and dates when I take my pictures.  If you enter the time stamp I wrote above, you will get this:

Now while my original source image is nice, I knew I could improve upon it with other images taken that same night at my telescope.  After accentuating Callisto’s brightness a little so we can see it, I used Photoshop Elements to carefully cut out Jupiter and its four moons.  I then overlayed these into a properly-exposed wide-field Moon image.

Next, I wanted to get a good Jupiter into the picture, since the planet itself is overexposed in all my tripod images.  I created the following image from stacked video at my 10″ Dobsonian:

I will shrink this good Jupiter to overlay into the main picture were the bright overexposed Jupiter resides.  But I also wanted to get the planet’s angle right relative to the moons.  So I imported as a temporary layer this other picture I took on Sunday that I previously wrote about:

This “moon” image is the perfect gauge, first to align with the native orientation of Io and Europa in the main image, and then to align the good Jupiter with the moon image Jupiter.  With the proper angle, I then overlayed this good Jupiter on top of the overexposed Jupiter, shrinking it a bit to compensate for the over-brightness of the original.

The final result is the image at the top of this post.

As a final perspective, I used the telescope Moon image I posted earlier and overlayed it in, and then moved the Jupiter system next to the Moon.  This gives you an idea of how wide an area Jupiter and the Galilean moons take up in reference to our Moon:

Click to enlarge.

That’s all for now. I am hoping with the Moon waning over the next week that I will be able to take more constellation pictures, and possibly a few deep sky objects.

Grinding a Telescope Mirror: The Non-DIY Project

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John Dobson

I did not know John Dobson, nor do I know someone who knew him, but I feel like I did from all the testimonials I have read.  At the least, my telescope build is an extremely distant branch of his legacy.

Mr. Dobson is the namesake for what is commonly referred to as the Dobsonian telescope.  He did not invent this type of telescope, but instead ingeniously brought together a number of amateur telescoping making (ATM) techniques.  This compilation is a method with general designs for how to build your own Newtonian reflector on an altazimuth (up/down left/right) swivel mount.  Sometimes you see references to only the mount as the Dobsonian part, but a true Dobsonian refers to the complete package, from the mount to the tube to even hand grinding the primary mirror.

This latter part, concerning the primary mirror, is what I stumbled on conceptually at the beginning of my telescope build journey.  When you start any type of project, and especially when you undertake what we call DIY projects today, you will have many “make or buy” decisions.  How much of the project will you, personally, create from raw materials, and how much will you rely on pre-built/pre-manufactured components?

Platonically speaking, there is no such thing as a true DIY project.  I am not going to grow my own forest to harvest trees for wood, nor start a lumber company to secure the requisite labor and machinery for my platonic lumber mill.  Nor would I obtain raw silicon to fabricate my own nano logic gates for a homemade CPU.  Still, there is a generally accepted boundary for raw materials – products that are not a specific end to themselves but are intended to be reshaped and combined with other raw materials into some form of finished component.

The primary mirror of a Newtonian reflector is indeed the main component of the telescope.  Its aperture determines everything else about the telescope’s dimensions and how “powerful” the final instrument will be.  The creation of primary mirrors is a deep step into the peculiar world of optics.  Remember the Hubble Telescope’s original blunder of having the wrong curve on its mirror?  That’s optics.  Whether we are talking big or small mirrors and lenses, the universe of optics and optical creations are not really an end-consumer endeavor.  There is a level of precision required unique to that industry.

If you follow any guide on John Dobson’s telescope build strategy, you will quickly learn that construction of the primary mirror was the core task of his method.  Below is what I assume was an old VHS era documentary on Mr. Dobson’s step-by-step approach, and most of it (a little over half) is about grinding and finishing the primary mirror.

If you watch this, or follow another guide on the Internet for grinding your primary mirror, it seems to be truly a daunting task.  It is beyond hard work and effort and closer to a stint in a hard labor camp.  Why would anyone do this to themselves?

I am in no way criticizing the method John Dobson laid out.  Too often, we judge the past by our perspectives grounded in our present.  60 years ago, the nature of amateur telescope making was very different.  There were no online guides, no easily searchable list of vendors to purchase obscure products from.  If you wanted a big telescope, I’m guessing the overall costs were too prohibitive for anyone except established institutions.  If you wanted to build a nice big telescope of your own to see the universe, you had to build your own, even scavenging for your raw materials at times.  This, I surmise, was the world of John Dobson and the source motivation for what would become the Dobsonian design.

I asked myself, “could I grind my own primary mirror?”  My weak answer was…maybe.  I have completed DIY projects before, but the grinding of a primary mirror seemed beyond my need to satisfactorily say that I could build my own telescope.  There is so much more to it than just the primary mirror – the tube, the many proper measurements, the mount wood cutting, the secondary mirror’s spider, the swivel construction, to name a few.  I decided that acquisition of the primary mirror, and all the optics in general, would be a firm “buy” decision for my telescope project.

There are other reasons to refrain from a homemade primary mirror as well.  I concluded, after all the investigations I did into the task, that there is no such thing as a true homemade primary mirror.  A DIY build means you can run to your local hardware store, buy the parts, and then construct what you need in your garage or other appropriate home venue.  Construction of a primary mirror requires, as a final step, the aluminization of the mirror’s surface.  This critical step is not a home DIY task.  You would need to find an industrial optics company willing to perform the aluminization for you.  You can spend weeks of your life grinding the mirror, then be lost because you cannot find an aluminizer.  Unless you know someone, you are going to be left having to ship your precious near-finished glass to an unknown company, somewhere and at great cost, hoping it will eventually be returned as the desired finished product.  I’m not saying it couldn’t be done, but I safely believe it is too much of a risk of both effort and money, especially when you can buy a finished primary mirror relatively easily today.

I say “relatively” easily to buy a primary mirror, because even that was a challenge, although nowhere near as hard as grinding one yourself.  For what I call consumer high-range optics, it can be very hard to find a supplier for this type of work.  Only a few online merchants offer shopping-cart style access for primary mirrors, and their supplies are limited.  Many companies post that they will make custom mirrors, but usually at a high cost, or only make very large custom mirrors, like 16″ and above.

We live in a much different world today from when John Dobson started building telescopes.  The bottom line is that, unlike most DIY projects, it is going to cost you more to build your own Dobsonian, regardless of make-vs-buy for the primary mirror, over purchasing a commercial Dobsonian or general reflector from one of the big established merchants.  So from the DIY perspective, your best route is to find one of the vendors or re-sellers of the commercial primary mirrors supplied to the Meades, Celestrons, and Orions of the market.

Who should attempt to grind their own primary mirror?  For one, masochists, and I mean this in all seriousness.  Another group that could reasonably give it a shot are those involved with any type of materials shop, from wood to metal, where building anything is just part of your routine.  And those connected to building components for the optics industry could certainly do this as well.

For the rest of us, if you really enjoy a challenge, then grinding a mirror is for you.  But for nearly all stargazers contemplating building their own telescope, I recommend purchasing all your optics, including the primary and secondary mirrors, focuser, eyepieces, and finder scopes.  Your homemade telescope will be so much more than a few specific components.  It is the journey, the knowledge you will gain, and the final satisfaction garnered from creating something far greater than the sum of its individual parts.

Which Deep Sky Objects are Good to View Right Now?

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Last week, when viewing conditions where still great and just before I got a bad cold, I was perusing the skies with my big (10-inch Dob) telescope.  It had been a while since I was outside with the heavy equipment just browsing for new stuff above.  So after taking a good look at all things Orion and the Pleiades, I used my Sky Map app to see if any DSOs might be worth viewing.

Since they were around Zenith (and still are) at my best night viewing time, I decided to look for three open clusters, Messier objects M36, M37, and M38.  They are in the constellation Auriga, above Orion and Taurus.  All three clusters are nice, but I found M37 in particular to be amazing.  Even from my light-polluted suburban skies I could see dozens of concentrated stars, if not more.  It had been a while since I had an awe-inspiring find, and this was finally it.  I am hoping, if weather conditions improve this coming weekend, to try sketching M37.

We are in the middle of Winter and looking towards Spring.  Are there any deep sky objects you enjoy viewing at this time of year?

How to (and not to) Get Kids Interested in Astronomy

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Through my studying of astronomy and stargazing, as well as interactions with my younger relatives, I have come to opinions on the best methods to introduce children to the wonders of the sky.  Some are obvious, and you will find these in most any Internet advice write-up on the subject.  Others are not so much, and may even be contrary to other guides.  Still, I feel these are sound recommendations based on research, experimenting, and common sense.

First, What NOT to Do!

#1 Expensive Does Not Equal Better!  Do not go out to buy the biggest, most expensive telescope you can afford.  It is nearly a guaranteed waste as far as children’s use.  Any telescope over US $200 is not worth the entry price.  Note that for adults getting into astronomy, this may be viewed slightly differently.  While adults should still not, under any circumstances, spend thousands of dollars on a first telescope, you may factor in your risk sentiment if you want try for a more advanced first scope like a Mak-Cass.

#2 Too-Big Binoculars  Avoid binoculars at first for kids.  I know this may go against popular thought, but hear my reasoning.  Binoculars are (a) bulky, (b) difficult to steady, especially for kids, and (c) not an intuitive learning instrument for children.  In short, binoculars take practice to use correctly, and you don’t want your kids’ first stargazing experiences to be of them thinking they need to hit the gym to hold up those binoculars all night long.

Again for adults, the case for binoculars is different.  As this is meant to be a kids’ article, I will table that discussion for now, and write an adult’s guide to beginning astronomy later.

#3 Meteor Shower Hype  Stargazers get excited when meteor showers come around annually, but let’s be frank – they usually require a boring wait and almost never live up to expectations.  While older folks like me may have no problem sitting in the dark at 4 a.m. enjoying the sky, younger people and particularly kids will not be so patient.  I feel it is best to avoid meteor showers altogether unless you can appropriately time box the event with realistic expectations of what may be seen.

orion-nebula-02#4 Bright, Colorful Objects Need Not Apply  We all know of those wondrous images of nebulae and galaxies with countless stars that look so magnificent and vibrant.  But what you need to understand is that those pictures are achieved from intense post-processing of many long-exposure camera images.  This isn’t to say those images are a lie, only that it is impossible for the human eye to view them like that from any telescope.  These objects are thousands and millions of light years from us, and the photons (light) from them are extremely limited.  The techniques used to get amazing pictures of deep sky objects capture as many photons as possible, usually over hours of imaging exposure, well beyond what our eyes could ever hope to see.  Think of paint slowly dripping onto a canvas to eventually form a picture.

Most deep sky objects as seen through a telescope will likely be gray.

Before Proceeding, A Public Service Announcement…

As a general warning, NEVER use an optical device to look directly at the Sun unless it has a proper solar filter secured to the front (not the eyepiece side, but to the other, big end).  Permanent eye damage can result!  My advice for solar viewing with telescopes is to SKIP IT, at least at first, until you the responsible adult are familiar with your telescope and understand how to properly attach and use a solar filter.  Focusing on only the nighttime sky is more than enough for kids when starting out.

My Steps for Children’s Astronomy

#1 Just Look Up  It’s easiest and costs nothing to step outside on a clear, dark night and enjoy our galaxy’s showcase.  Granted, your mileage will vary based on light pollution, with extremely dark skies making objects even beyond our galaxy, like the Andromeda Galaxy, visible to the unaided eye.  But still, have them see the Moon, bright planets, and bright constellations and star patterns (asterisms).  A variety of star map apps for your phone or tablet can help to locate what is in the current night sky.  If you are reading this in Winter (in the Northern Hemisphere), by all means focus on Orion the Hunter!

Again in the Northern Hemisphere, the Big Dipper (Bear), part of Ursa Major, is always visible at least in part year-round, so it makes a great first star pattern for kids to learn (after Orion, which is not always viewable).

#2 Get a Star Finder Dial/Map  You likely know what I am talking about – those pinwheel star maps that you rotate to see the visible stars for your time of year (normally at a preset time of night).  They are inexpensive and a good entry point for kids to learn about what they are seeing above.

#3 Get an Children’s Beginners Astronomy Book  It probably makes sense to acquire this along with the pinwheel star map.  I am not promoting any particular book, and I trust it is not too hard these days to do an Internet search to find several good books that offer beginner’s lessons on astronomy.  A perquisite should be good pictures, especially of the constellations, so that kids can relate what they are seeing to what is shown in the book.

#4 Persistence  Keep letting the kids see the night sky when possible, but without overdoing it.  Try for good nights on the weekends.  At the very least, show them the changing phases of the Moon.

Are the kids still interested by this point?  If so, now you can consider buying a telescope!

# 5 Buy a Good First Telescope  You will want to get a good beginner’s refractor telescope from one of the “big three” merchants in the U.S. (may be different in Europe and elsewhere).  These are Celestron, Meade, and Orion.  I am not promoting any brand or company, so I will just say to go for a 60-70mm refractor with two eyepieces (high and low power), and offer up one suggestion from each:

celestron-astromaster-lt-70

Celestron AstroMaster LT 70AZ

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Meade Infinity 70mm

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Orion StarBlast 70

Also, get a 25% Moon filter along with the telescope (I think 25% makes more sense for a refractor’s small aperture, versus the normal 13%, but you could get by with 13% too; 25% and 13% are just indicators of the total amount of light let through, so 25% only shows a quarter of the total visible light).  This will dim the Moon, making features easier to see and only costs about $20.  Remember to use the Moon filter only for the Moon!  It will otherwise make planets (except Venus, see below), stars, and deep space objects too dark for the human eye to enjoy.

Why a refractor?  It is the most basic of telescopes and requires little if any maintenance.  Reflectors need ongoing maintenance, called collimation, which may be a bit too much for kids just starting out (and the adults supporting them).  Collimating a telescope is not hard, but it is also not a core activity to enjoying astronomy.  Any other telescope variety, like Maksutov-Cassegrains, SCTs, and apochromatic refractors are too advanced and/or expensive for young beginners.

A side benefit to simple refractors is that they may be used for daytime terrestrial viewing as well.

#6 Set YOUR Expectations of the Telescope  As the responsible adult, learn how to operate your telescope.  This seems basic, but you should understand how to quickly adjust the telescope, as objects move very fast in the sky.

What will you see?  Refractors offer a very wide view, which is nice when viewing groups or stars or the surroundings of the Orion Nebula.  They will reveal small but still discernible views of the planets.  All of these views are perfectly fine for beginners.  Always start with your low-power eyepiece (e.g. 25mm) and switch to the high-power (e.g. 10mm) to zoom in.

#7 Show Them the Stars  Use the telescope on bright stars.  You and your kids will be amazed at how each of these gems look, as well as noticing the surrounding faint stars only visible through the telescope.  As an added treat, look for double-stars – stars that look like one to the eye but are actually two stars in the telescope!

#8 Show the Partial Moon  Use the telescope on the Moon.  Focus not on the full Moon but on the phases.  Those are the most interesting through a telescope because you can see the crater shadows.

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#9  And Last, Show the Planets  I am recommending to focus on the planets last only because they will appear small through a 60-70mm refractor.  But they will still be impressive in their own rights.

Here is a breakdown of the what to expect with each planet:

  • Mercury – this planet is so elusive I recommend not searching for it with a telescope, for beginner kids.  If you have ideal conditions of clear skies and with Mercury at an ideal distance above the horizon (dawn or dusk), then you can give looking for it a try, though keep in mind it will be very tiny in your telescope.  I also don’t recommend viewing Mercury to eliminate any chance of looking at either the rising or setting Sun.
  • Venus – it will be very bright and never a full disc, being anywhere from about 80% to a thin crecent.  You will only be able to make out the shape and not planetary features.  Hint: if you do have a Moon filter, Venus is the one planet you can try it on.
  • Mars – this planet’s brightness will vary the most.  When Mars is at opposition to Earth, it will be very bright, even rivaling Venus.  You may be able to see some planetary features, like the dark mara and polar icecaps.  When Mars is far away, it is very dim, and very small in any telescope.  These extremes are due to Mars being small and its wildly varying distances from Earth.
  • saturn-20160805Jupiter– the largest planet will consistently look like a bright star.  Though small, you will see up to the full four Galilean moons and the planet’s cloud bands.
  • Saturn – will appear like a faint star.  Through the telescope, you should be able to see its rings.
  • Uranus – too faint to find with a beginner’s telescope, or at least it is not worth the effort.
  • Neptune – ignore this planet as it is too dim and distant for beginner’s astronomy.
  • Pluto (the non-planet planet) – searching for and finding Pluto requires an advanced technique, so ignore it as well.

#10 Try Sketching  Wait, what?  Sketching?  Yes, I really believe that sketching both the direct sky as well as through the telescope will be a surprisingly fun activity for children.  It does not take a lot to do but requires a bit of preparation:

  1. Get a small red flashlight (one per child so there is no fighting over one flashlight).  Red is needed to keep our eyes acclimated to the dark.
  2. Obtain a solid writing pad with paper and pencil (one set for each kid, of course).
  3. Optionally for telescope sketches, use a compass to draw a big circle to frame the eyepiece view.
  4. Some kids will prefer to sketch the open sky’s star patterns while others will want to focus on the telescope view.  Either approach is fine!
  5. Instruct the children to start by drawing the brightest stars first in recognized patterns like lines, triangles, and rectangles.
  6. Once the bright stars are complete, they can turn their attention to filling in the details of the fainter stars between the bright ones, if they so wish.  Many children will be proud of their work from just sketching Orion’s primary stars, as an example.
  7. Make sure each kid writes the date and time of their sketch on their drawing, as well as a short description of what they drew.

I hope these ideas help in getting your kids interested in astronomy.  If you have any comments on my guide, or suggestions, please leave a comment below.

Lighting Up the Bull

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February 14th, 2017, 8:40 p.m. local time

For all the griping I’ve written here about light pollution, I have to admit that the wonders of the night sky are still aplenty for me, and sometimes offer wonderful surprises.

As I was scanning Orion both through my telescope and via unaided observing, I noticed something I had not before.  Around Aldebaran, the brightest star of Taurus, were a whole bunch of dim stars.  Usually I ignore Taurus, since its sole visible representative, Aldebaran, does not offer much, beyond gauging its relative spacing with everything else in that area of sky.  But tonight, being clear and with no Moon and my eyes properly adjusted, I could see a number of stars in proximity, just to the West of Aldebaran.

This event made me realize that you should not take any part of the night sky for granted!  I will try to do a better job studying my sky’s “empty” spaces.

When I Decided to Build a Telescope

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When you enjoy using your telescope to look at the night sky, you are bound, one day, to decide that you want a second telescope.  You may have “aperture fever” to gather more light, to see more.  Or you may have a reflector and want to complement it with a refractor.  Big vs. small.  Stationary vs. portable.  Sketching vs. astrophotography.  There are many reasons you will (and you will) consider having a second telescope.

Almost a year ago, I bought my first “real” telescope, a 127mm Maksutov-Cassegrain.  It is relatively small in the overall scale of telescopes, but I did not want to buy too much in case I quickly lost interest.  But I did not lose interest, and really enjoyed using it to view the Moon, Jupiter, Mars, Saturn, and the Sun (with appropriate solar filter).  I have also used it to view deep space objects like the Andromeda Galaxy, star clusters, and nebulae.  Although the latter are viewable, it is clear to me that my small 5-inch Mak-Cass is primarily intended for solar system observations.

After a few months, I decided to investigate getting a second telescope that (1) had a noticeably larger aperture and (2) would specialize in viewing deep sky objects.  I immediately understood that the most obvious trade-off would be in size and weight.  If I desire, I can take my 127mm Mak-Cas anywhere with minimal effort.  But something far bigger would likely require greater setup and planning to transport, even just from my house into my yard.

I also wanted to at least leave the door open for astrophotography.  With the Mak-Cass, I use the afocal method to take pictures.  Afocal photography is just a fancy term for holding a camera up to an eyepiece (versus the more sophisticated method of bypassing the eyepiece and using a proper T-ring or other adapter for a DSLR camera).  I have a few afocal adapters that allow me to take pictures with my smartphone; most of the pictures on this blog were taken afocally.

After reviewing the major types of telescopes, I was leaning towards a Newtonian reflector, specifically a “Dob” or Dobsonian.  I will blog about the Dob’s namesake, John Dobson, in a future post.  Reflectors in general are the most economical per size, and are intended solely for night use (since the images appear upside down, you can’t really use them for terrestrial applications).  They are also primarily intended for eyepiece viewing, versus photography, but some sort of photography method is entirely possible if you want to.

I went down the path of reviewing Dobs from the major telescope companies (there are three primary ones in the U.S.A. – Celestron, Meade, and Orion).  During my investigations into price and features, somehow I came across the idea of building a homemade telescope, from scratch.  This intrigued me, as I had built a few other projects around the house before, even though I am not a craftsman by trade nor do I have any type of workshop (except for the half of my garage that becomes a de facto workshop when I do one of these projects).

If you search online for homemade telescopes, you will see a wide range of designs and efforts.  Some look crazy.  Some are well beyond anything I would attempt.  But others seemed far more modest and manageable to execute.  After a lot more research, I decided to give it a go.  I figured that a telescope, after all, is ultimately a technology hundreds of years old, so with the right planning and designs, it should not be too difficult for anybody like me to build one.

And building a telescope, I thought, would come with a great sense of accomplishment.

So I intend to write about my telescope building experience.  I will not write a “how to” guide, as there are a number of perfectly acceptable guides on the Internet, as I will reference.  Instead of a step-by-step chronology, I plan to give insights into my efforts over the several months it took to plan and build.  When I am done, you will probably have a adequate idea anyway of how I built my 10-inch Newtonian reflector on its Dobsonian mount.

In my next telescope build post, I will discuss one of the first major decisions – whether to build or buy the primary mirror.

Finally Found The Little Dipper

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Earlier this week I wrote about my problems finding The Little Dipper (a.k.a. Ursa Minor, The Little Bear).  The past few nights have offered good views of the sky, so I went outside and, sure enough, I finally managed to “size” The Little Dipper properly.  Polaris is easy to find.  In hindsight, my main issue was that I always thought this constellation was much smaller than it really is (being “little”).  But by using the asterism The Big Dipper (part of Ursa Major) as a guide, it became fairly obvious where the two end stars Kochab and Pherkad were.  They are easily visible to me without an optical aid.

So in between Polaris and the Kochab/Pherkad set are the other four points of The Little Dipper.  They are much fainter and I could not obviously see them at early night with a big Moon, though I suspect I saw at least one.  I will wait for a dark (no Moon) night with my eyes properly adjusted to seek the rest of this constellation.  The great news is, from my location in the U.S.A, The Little Dipper is visible all year, every day, clouds permitting.

My Vexations in Finding The Little Dipper

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One of my most obvious “misses” in observing the sky this past year has been The Little Dipper, a.k.a. Ursa Minor.  Whenever I say to myself I will focus on it on clear nights, I get distracted by some other, more interesting part of sky.

Why is The Little Dipper so hard to find?  I think it’s a combination of factors:

  • Since most of its stars are well above 2 magnitude, the excessive light polution in my area masks most of it
  • Difficult to judge its size relative to The Big Dipper, which is very bright
  • Finding Polaris is an easy nightly win that usually does not go much further
  • Generally boring part of the sky, party due to light pollution – Zenith and towards South are far more interesting (think Orion and planets)

I frequently spot Polaris, which at least is a good start.  My difficulty starts in that the rest of that area of sky appears blank, especially right after nightfall.

Reviewing the constellation and the brightness of each star, I now have a strategy to find it:

  1. Wait for a clear sky with no or little Moon
  2. Wait until the sky is sufficiently dark for the evening
  3. Locate Polaris, which is always easy
  4. Next, and here is the key, is to determine the approximate location of The Little Dipper’s next brightest star, Kochab.  It is supposed to be only slightly less bright than Polaris.  My guess, now that I think about it, is that I simply miss or ignore Kochab.

Since Polaris and The Little Dipper are effectively at the center of our cosmic wheel, it should just be a matter of gauging which position on the “clock” Kochab is to Polaris.  And for added perspective, I need to study the relative size differences of the two dippers, and use it as a marker as well in finding Kochab.  In hindsight, I think one of my bad assumptions is that Ursa Minor is far smaller than it really is.

So once I have Polaris coupled with Kochab, I can use either my telescopes of binoculars to trace out the rest of the constellation.  We’ll see how this strategy works on my next clear, dark night!