Tag Archives: Coronado Pst

CNYO Observing Log: Baltimore Woods Solar Session, 24 August 2013


The gathered crowd at Baltimore Woods.

Greetings fellow astrophiles!

As CNY completes a remarkable span of bright days and clear nights around this year’s Harvest Moon, we finally catch up on our observing logs with a recap of Baltimore Wood’s Solar Session held on an equally bright and clear August 24th.

Despite its importance as the primary reason we and this Solar System are here at all, the Sun often gets neglected by some amateur astronomers who opt out of expensive solar equipment in favor of expensive deep sky equipment. The Sun, like all stars, is a seemingly simple ball of light that reveals great complexity depending on what you use to observe it. Some filters knock down all but 0.001%(ish) of the Sun’s light to provide great Sunspot detail, while other filters let only very specific wavelengths of light through – these filters then providing insights into the surface structure of the Sun based on the excitation of specific atoms on the Sun’s surface or in its corona.


An observer at a Coronado H-alpha scope.

Despite its close proximity and constant activity, the Sun is just like any other astronomical object – patience is the key to appreciating the view. At low magnification and over only a few minutes, Sunspots and prominences appear to drift slowly, if at all, in the field of view. Changing to high magnification reveals dynamic views around Sunspots as they undulate or merge with other spots, with changes that are apparent to trained eyes occurring over many seconds. Observers with good memories can return to their scopes over several minutes to see very obvious changes to large prominences. While the differences may be subtle to the eye, they are anything but subtle on the Sun. Keeping in mind that 107 Earths fit across the diameter of the Sun, seeing changes to large prominence over the course of minutes means that plasma on the Sun’s surface is racing at dizzying speeds. The drama only seems slow from our safe distance.


The gathered scopes (and gathering observers).

The two hour session at Baltimore Woods provided ample time to sample both the range of filters and the range of timescales, thanks primarily to the ever well-equipped Bob Piekiel and his Baader, CaK, and H-alpha scopes. To this list of equipment was added Larry Slosberg and his Baader-filtered New Moon Telescope 12″ Dobsonian (the big primary mirror of the session), then myself with a Coronado PST (H-alpha). And speaking of filters (and taken from CNYO’s A Guide For Solar Observing brochure)…


A solar projecting scope (left) and Larry Slosberg’s Baader’ed NMT Dob.

Baader Filter – The Baader (“Bah-der”) filter works by reflecting 99.999% of all of the incoming light (almost a mirror), leaving you with a pale yellow disk. You’ll see no prominences or fine surface detail, but Baader filters are excellent for observing sunspots.

CaK (Calcium K-line) – The CaK filter lets through a wavelength corresponding to the 393.4 nm Ca K-line transition (you see it as violet). These filters provide excellent surface detail.

H-alpha (Hydrogen-alpha) – This filter lets through a hydrogen electronic transition corresponding to a wavelength of 656.28 nm (you see it as a rich red). H-alpha filters are excellent for prominences and good for surface detail.


The Sun through different filters (see above).

Thanks to the SOHO (Solar And Heliospheric Observatory) satellite and its website, it is easy to find the Sun’s snapshot on August 24th to see exactly what we were looking at, complete with a week’s worth of images from the days before to see how the positions of Sunspots changed as the Sun’s plasma rotated about its axis (the final image in yellow is the view from the 24th).


The week before the solar session (images from NASA/SOHO).

Technical details aside, the session was an excellent one, with approximately 30 people enjoying many views of the Sun and all the solar details Bob, Larry, and I could remember. Of specific note was a prominence that started small at the beginning of the session but grew to contain a clear, dark hole more than one Earth diameter wide over only an hour’s time. The fun wasn’t restricted to scope observers, either. With filtered binoculars and simple Baader glasses, the dimmed ball of light itself was just as interesting a target.


The unmagnified (and nearly unmagnified) view of the Sun through Baader glasses.

While I didn’t hear it mentioned, it is worth noting that the unmagnified (but filtered) Sun appears to be about the same diameter as the unmagnified (and unfiltered) Moon – a point of no small significance during Solar Eclipses. And as the Moon is slipping away from us at a rate of 1.5 inches per year, the Solar Eclipse is also (very, very slowly) becoming a thing of the past in favor of what will become Lunar Transits. All the more reason why it’s a great time to be observing!

I leave you with the most informative 30 seconds on the website (so far). To demonstrate the dangers of observing the Sun without some kind of filter, Bob and Larry set to work reproducing the fabled ship-burning apparatus of Archimedes (also of Syracuse) by burning one sheet of paper and one dark leaf at low magnification. As Bob explains, this same burning would occur on your retina without something to greatly knock down the Sun’s brightness. I even found myself jumping rather anxiously at one intrepid observer trying to look through the eyepiece of Bob’s projecting scope. Solar safety (and eye safety in general) is no joke!

It’s as informative and definitive a video on solar safety as you’ll find on youtube, so feel free to pass the link along to any and all.

Barlow Bob’s Corner – Think Outside Of The Box – NEAF 2014 & Occultation Email Highlights

Greetings fellow astrophiles!

I am very happy to summarize some recent emails and a new article from Barlow Bob, founder & organizer of the NEAF Solar Star Party and regional event host & lecturer on all things involving solar spectroscopy. You can read more about Barlow Bob and see some of his other articles at www.neafsolar.com/barlowbob.html.

NEAF 2014 Dates


The 23rd Anniversary edition of the Northeast Astronomy Forum, America’s Premiere Astronomy Expo and certainly the largest event of its kind on the East Coast, will be April 12 (Saturday, 9 a.m. to 6 p.m.) and 13 (Sunday 9:30 a.m. to 5:30 p.m.) at Rockland Community College in Suffern, NY. Both days of the event feature the NEAF Solar Star Party and its organizer Barlow Bob. Get those taxes done early!

See www.rocklandastronomy.com/neaf/index.html for more info.

Occultation Of Regulus – March 20, 2014

Barlow Bob forwards the following from Glenn Chaple on the occultation of Regulus by asteroid Erigone. Better still, CNYO members may be helping the International Occultation Timing Association (IOTA) with their monitoring experiment. We will keep you posted as March 20th approaches. Meantime, check out the video below to see what to expect.

And, without further ado…

Think Outside Of The Box

By Barlow Bob

There are a wide variety of amateur astronomy products available today, manufactured by astronomy suppliers including Celestron and Meade. These types of companies are a great resource to amateur astronomers.
However, if you think outside of the box, there is an even larger variety of other suppliers of amateur astronomy products including Stanley, Cabela’s, L.L. Bean, Gander Mountain, Eastern Mountain Sports, Dick’s Sporting Goods, Home Depot, Sam Ash Music, Ritz Camera, Bass Pro Shops, Titleist and most any art supply store. These other companies supply a wider variety of padded, rugged, waterproof cases to hold expensive guns, tools, cameras, golf clubs, music instruments, and fishing equipment. They also supply warm waterproof sportswear and camping equipment. 
Some stargeezers are downsizing their amateur astronomy equipment. The 25” Obsession bought for their 30th birthday is now too hard to use on their 60th birthday. It has become a problem to move my variety of heavy amateur solar astronomy equipment at various amateur astronomy events, like NEAF – The Northeast Astronomy Forum – each year.
I use a padded drum case to hold the top cage of a Dobsonian telescope, then small cases for mount parts.  I store my Herschel wedge in a diced foam camera  equipment case.  I store the wooden legs of a mount in padded rifle cases. The tripod legs are covered with knitted gun socks. Shorter knitted gun socks cover PowerMate lenses and imaging extension tubes. Padded pistol cases hold smaller toys. I use a two-wheel golf bag cart to move heavy surveyor tripod mounts. I use a large art carry case to hold a big square piece of heavy duty clear plastic.

A smaller art carry case holds a TV swivel stand. Large sturdy plastic food storage containers hold mount weights. A large canvas tool bag holds the head of my equatorial mount and mount parts. Several small Stanley canvas tool bags allow me to store all of the parts of one astro toy in each separate bag, each bag labeled with the contents enclosed. When I go to an event, I can just take a toy and the small bag containing the parts for the toy – no more lost toys or parts.

Larger bags carry more equipment, but become extremely heavy.
You probably have already found many other similar products that you use.

I encourage you to think outside of the box and make it easier for you to move your own astro toys.

Poster’s Note: Great minds have thought alike! During our last phone call, I had mentioned to the Barlow’ed One that I not only use a molded, hard floor tom case (you can get locally from Guitar Center or, my personal preference, The Music Center on James St.) for the secondary cage of my New Moon Telescope Dobsonian (and the case doubles as a table and storage bin during observing sessions) and a drum stool for my sitting duties, but I also put together my own custom Coronado PST case from a Sterilite container and green foam from Michael’s (shown below, at a savings of $70 over the official case).


CNYO Observing Log: Camp Comstock, Ithaca, 1 June 2013


One of the great joys of public observing sessions is introducing non-observers to the immensity of our local sliver of the universe. Hubble imagery and the amazing ground-based astrophotography of the last 25-or-so years is all well and good, but to explain to a new observer that the photons from the Whirlpool Galaxy (M51) currently hitting their retina have been on a 23 million year voyage, or to put all of the Andromeda Galaxy (M31) into the field of view and explain that the photons on one side of the eyepiece have been traveling 150,000 years longer than the photons on the “other” side of the eyepiece, or to aim a Coronado PST at the Sun and point out that the sunspots on the surface are 3 or more Earths across – these are the images that really put the universe, and our place in it, into perspective.

One of the great joys of lecturing on introductory astronomy is being able to describe all of these visuals in greater detail, showing how observation and the rest of the Scientific Method have produced great order in our Nighttime Sky (for, at least, the parts of the sky we can see in the backyard on a clear, dark night). As is true for many of the other physical sciences, a book chapter or wikipedia page alone can be far less informative, and is definitely far less engaging, than a chance to have a conversation with someone who knows the topic well enough to relate complicated concepts by drawing from many additional resources.

And, at a time when we continually fret the state of STEM education in the US, there is nothing better for an academically-inclined scientist (me) than to have someone many years their (my) junior process the information on a slide and ask a question that (1) clearly shows a grasp of the physics involved and (2) they (I) don’t have a good answer to. Lecturing keeps the lecturer just as sharp!

It is with those points in mind that CNYO hosted a Girl Scout lecture on Saturday, June 1 at Camp Comstock in Ithaca, NY as part of their requirements for earning their Night Sky badge. Unfortunately, the mostly cloudy and otherwise unpredictable night before made the Nighttime Sky observing component impossible, compacting the badge requirement section into a combined lecture/solar observing session that went well over allotted time with no (voiced) complaints.

Instead of highlighting lecture points, my goal here is to provide a few pointers for perspective astro-lecturers of kids and young adults (although I suspect the same applies for all generations).

1. Plenty Of Lead Time For Setup

In my case, my leisurely 1 hour drive turned into a compressed 40 minute drive as I waited for a police officer to take my eyewitness statements after a fender-bender on Route 13. Lesson #1 – Don’t text while driving!

2. Short Sections

Based on the Night Sky badge requirements, I had a very good template by which to design seven short lectures that would fit nicely into a 60 minute presentation (that, with questions, then went on for two hours). A full hour on a single topic to a general audience can be way too much for even a focused audience. Make this an audience of young adults and add an un-air conditioned, 85 oF room to the mix just after lunch, and you’ve got a recipe for a very… red-shifted lecture. A very good approach for you and the audience is to pick several topics and try to make a complete mini-lecture out of each. This makes your preparation time more productive (because you can divide-and-conquer as well) and it allows you to give the audience a minute between mini-lectures to digest and freshen up for the next one. In the Night Sky badge case, my seven sections were:

A. The Local Neighborhood

– A “powers of 10” walkabout from Earth out to the Sloan Digital Sky Survey

B. Circumpolar Constellations

– Explaining how the Earth moves (rotation vs. revolution) and why the North Star doesn’t appear to. This part of the lecture was complemented by the CNYO How The Night Sky Moves brochure.

C. Constellations (What & Why) And Stars

– An overview of Western constellations and the stars that define them, including a little discussion of stellar variety (color, age, size)

D. Why Learn The Constellations?

– Stress the historical meaning of the Constellations, then their use for direction (Follow The Drinkin’ Gourd) and use for marking deep sky objects (specifically, the Messiers)

E. Don’t Panic!

– How to learn the constellations, including the circumpolar-first approach, seasonal heavy-hitters, and the Zodiac

F. Solar System Formation

– Two videos I always keep handy in the back of a presentation are “Birth Of Our Solar System” (a nice animation of the formation of the whole Solar System)…

… and “How The Moon Was Born” (a video that shows the history of the Earth-Moon system and the ever-impressive Theia impact).

G. Light and Air Pollution

– Light pollution is bad, but it does help new astronomers find the bright starts in constellations. Air pollution also helps, but at a much higher cost. We should be avoiding both!

3. Ask Lots Of Questions

The biggest lesson I learned from watching professionals present to kids is to ask those kids lots of questions and let them be A driver in the presentation (but not THE driver, as you may never get the wheel back). It keeps the audience engaged, it lets others try to explain a concept in a way that the other-others may benefit from, it breaks up the monotony of the single-presenter approach, and it gives kids a chance to “show off” their scientific knowledge (which some of them love to do).

The best kinds of questions are (1) the very easy ones (how many planets) and (2) the ones that no one there (likely) has the answer to but that all can think about and take a swing at (alien life, what happens at a black hole, how big is the Sun, etc.).

If you’re lecturing to a group of 10 year olds, find a friend with a 10-year-old and see what they (don’t) know. If the kid isn’t astronomically-inclined, assume that their knowledge is similar to that of other 10 year olds in a Regents-guided state. The Girl Scout lecture was to a room of 13 to 17 year olds, and I am pleased to report that I had to move on to the “heavy questions” quite early in the lecture.

4. Preparing For The Power-Less Lecture

The Girl Scout lecture could have been done outdoors with demos or indoors with slides. Being a very visual science, astronomy lends itself better to slides unless you’ve several really good demos planned out beforehand (or brochures to help guide the discussion). There are several demos one can use to help get away from the slide-driven lecture and I hope to eventually get to the point of not needing any power. Simple demos (that will be expanded on in future articles) include:

A. Flashlights to demonstrate optical vs. true binaries (differently-colored flashlights are great for multi-star systems)

B. A tape measure and rubber balls to demonstrate the distances within the Solar System (if you’ve a 15 meter tape measure, you can place the planets at: 14.8 cm (Mercury), 27.3 cm (Venus), 38.0 cm (Earth), 57.0 cm (Mars), 197.7 cm (Jupiter), 360.8 cm (Saturn), 729.1 cm (Uranus), 1143.0 cm (Neptune), and 1500 cm (Pluto)

C. An armillary sphere (or big labeled ball) to demonstrate Earth’s axial tilt and its motion around the Sun (with a laser pointer serving as “Polaris,” a walk around an audience member serving as the Sun works perfectly well to help explain the circumpolar constellations

5. Anticipating The Unexpected Question(s)

When I think about the Sun, the first two questions that come to mind are not (1) Isn’t there a disease where you can’t be in the Sun because your skin breaks apart? and (2) I heard that some people try to live on only sunlight with no food. Isn’t that crazy (answer: yes)?

6. The Daytime Is The Right Time

As CNYO’s Larry Slosberg has determined for his observing sessions, the afternoon sky is a perfectly good substitute for the nighttime sky provided you (1) have a solar filter and (2) plan around the first quarter Moon. In the case of (1), the Sun is an excellent observing target for new observers because they very likely have never looked at it through filters and, as you can stress in your discussion, it is the reason why we’re here.


The Sun on 1 June, 2013. From SOHO/NASA.

As for (2), it is also a reason why we’re here, but the magnified Moon, either against a black or blue afternoon backdrop, never fails to impress. To help lead discussion at subsequent daytime observing sessions, the solar-centric Girl Scout session instigated the CNYO solar observing brochure available for download at: A Guide For Solar Observing.

And A Closing Thought…


CNYO Observing Log: ShoppingTown Mall, 17 April 2013


Greetings fellow astrophiles!

Our most recent solar session was organized by Larry Slosberg via facebook:

“Any up for an impromptu Lunar and solar observing session at Shoppingtown Mall at about 6pm? I’ll be heading to Scotch and Sirloin for a CNY Skeptics in the Pub at 7pm (you’re welcome to join that too) and thought, it’s such a nice clear night. Might be nice to get a couple scopes out and maybe get some people as they are leaving the mall.”

View Larger Map

The approximate location (at center) of the session.

With Larry’s 8″ Meade Schmidt–Cassegrain Telescope (SCT) (and homemade Baader solar filter) and my Coronado PST in tow, we hosted a 90 minute session before the CNY Skeptics meet-up with about one dozen attendees (and a curious ShoppingTown Mall security guard) and our two most prominent celestial neighbors – the Sun and Moon.


Larry and attendees #1.


The Moon was a 7-day-old waxing crescent on the 17th and high in the sky at 6:00 p.m. While Larry had his Baader filter at the ready, he ended up spending most of his observing time (due to crowd interest) examining all of the blue-on-grey surface detail that this late afternoon session afforded. A later evening image of the waxing crescent (from two days prior) is shown below from local astrophotographer John Giroux.


The waxing crescent Moon on 15 April 2013. Photo by John Giroux.


The Coronado PST filters nearly all of the incoming light from the Sun, making it comfortably observable and making anything else seen through the Coronado (short of a blindingly bright hydrogen lamp) pitch black. So, by necessity, my part of the session was dedicated solely to the Sun as it set in the tree-lined western DeWitt sky.


Larry and attendees #2.

The Coronado brings out sunspot, surface, and prominence detail using a 1.0 angstrom hydrogen-alpha filter (which is to say, that’s the only wavelength of light that gets through). The views are composed of ever-so-slightly different shades of red, but the detail is obvious with proper focus, magnification, and filter adjustment. The Sun was busy with prominences and highlighted on the surface by Sunspot 1745, shown at lower center in the image below from Ted Adachi’s submission to spaceweather.com that day.


The Sun, by Ted Adachi.

Over the course of 90 minutes of observing, I learned two valuable lessons for the Coronado. 1. Reducing some of the incoming light does a bit to help bring out some solar detail. Even covering the objective 50% produced detailed views that helped enhance some of the surface detail (as Larry demonstrates below). 2. The perfect eyepiece for filling the Coronado with a view of the Sun lies somewhere between 7 and 10 mm (a point that will be addressed in an upcoming discussion about NEAF 2013).


Larry demonstrates the light-block maneuver with a piece of reflective aluminum/bubble wrap.

With short notice, small scopes, and a clear sky, the daytime becomes just as interesting and enjoyable a time for an introductory sidewalk astronomy session as the night does. Young kids and adults alike get to take in a brand new view of our nearest neighbors while being able to see the scopes that make these views possible. And it is much easier to find missing eyepiece caps!

CNYO Observing Log: NASA Climate Day, 2 April 2013


Tuesday April 2nd marked the Museum of Science and Technology‘s hosting of NASA Climate Day in Syracuse, NY. For CNYO members and attendees attempting to observe the Sun, April 2nd also marked one of the more remarkable mixtures of weather patterns to hit CNY.


Patient attendees waiting for a clearing. Photo by Simon Asbury.

CNYO solar scope setup at Walt the Blue Dragon commenced promptly at 5:00 p.m. Given the expectation of snow and considerable cloud cover over the next few hours before the 7:31 E.D.T. p.m. sunset, I left my Dobsonian at home and Larry Slosberg opted to keep his Meade SCT in the car. Our equipment for the event consisted of a pair of 25×100 and 10×30 binoculars (both with homemade Baader filters) and one Coronado PST. Also in tow were several garbage bags for rapid covering of all the equipment.


The author looking for a clearing through Baader’d Zhumell 25×100’s. Photo by Simon Asbury.

The sky was windy, cloudy, patchy, and fast-moving, intermixing light snow with perfect blue patches near (but not always overlapping) the Sun. Over the course of about 80 minutes, only 10 good minutes of solar observing were had, and most of these involved some amount of cloud cover obscuring prominent Sunspot 1711 and several smaller Sunspots. The Coronado revealed a large triangular prominence and plenty of surface detail with a 20 mm Plossl and a TeleVue 3mm-6mm Nagler Zoom. It was during the Coronado observing that Bob Piekiel mentioned a certain tweak that can be performed to the PST (and other models) to improve the view (a forthcoming article documenting the procedure is in the works!).


View of the Sun on April 2nd, 2013. From sohowww.nascom.nasa.gov.

The outside part of the NASA Climate Day festivities ended as a massive grey cloud approached from the distant East (that proved to drop the largest amount of snow on Syracuse not 30 minutes later), instigating the packing up of equipment and migration into the MOST itself to see the rest of the event. In all, only a few left the climate-controlled confines of the MOST to see the filtered Sun, but we did get a few passers by to look, at least one of whom made it onto our facebook page recently.

LESSON FOR THE SESSION: When it’s freezing cold, blustering-ly windy, dark-grey overcast, and only a slight hope for long patches of clear skies exists, keep the solar scopes close to the exterior doors of the building where the main event is going on.

The indoor part of the CNYO session consisted of a small presentation area for showing a few videos of solar events, how the Baader and Hydrogen-alpha filters (in the Coronado) work (having stolen an incandescent light bulb from a bicycle-powered demonstration for the Baader demo), and the relative sizes of the Sun and planets in our Solar System. We moved inside just as Dave Eichorn began his keynote lecture and unfortunately missed his presentation, but that did give us time to walk around the displays near our little setup (appropriate placed next to the vision display).


The indoor presentation setup.

The demo of the Baader film with the incandescent bulb (to easily see the spring inside) was one of the indoor highlights (well, I thought is was interesting), then we finished the evening with a few students asking some very good questions about solar activity, the dangers of space flight, and potential plans for Moon and Mars Missions (which is always the real highlight of any CNYO session for me).