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Welcome to Houston Astronomical Society

Fostering the science and art of astronomy through programs that serve our membership and the community. Founded in 1955, Houston Astronomical Society is an active community of enthusiastic amateur and professional astronomers with over 60 years of history in the Houston area. Through education and outreach, our programs promote science literacy and astronomy awareness. We meet via Zoom the first Friday of each month for the General Membership Meeting and the first Thursday of the month for the Novice Meeting. Membership has a variety of benefits, including access to a secure dark site west of Houston, a telescope loaner program, and much more. Joining is simple; you can sign up online or by snail mail.

The Garnet Star

by Bill Pellerin, previously published

Object: The Garnet Star (SAO 33693; Mu Cep)
Class: Star
Magnitude: 4.08 (variable 3.4 to 5.1)
R.A.: 21 h, 43 m, 30 s
Dec: 58 degrees, 46 minutes, 48 seconds
Distance: 5,260 LY
Constellation: Cepheus
Optics needed: Naked eye, binoculars or small telescope

Why this object is interesting.
This bright (but variable) orange or reddish star is easy to
spot and is high in the sky at this time of the year. It transits
at 9:13 p.m. on October 20. The star sits on the edge of
The star is very large at 2.4 billion miles across. This is
larger than the orbit of Saturn and 1650 times the diameter
of our Sun. The period of variability is 730 days.
It was Sir William Hershel (1738-1822)
who gave it the name the 'Garnet Star'.
One problem with this description, of
course, is that garnet rock show up
with different colors. Which one did he
mean? There are even reports of the star
appearing to be purple to some observers,
although the star is designated as a 'M'
star. This is how he described the star in
the transactions of the Royal Astronomical
A very considerable star, not marked by Flamstead, will be found
near the head of Cepheus. It is of a very fine deep garnet colour,
such as the periodical star o ceti was formerly, and a most
beautiful object, especially if we look for some time at a white
star before we turn our telescope to it, such as a cephei, which is
near at hand. (from web site)
The Garnet Star's history is typical for a star of this size.
The star burns (fuses) hydrogen into helium early in its life,
releasing energy in the form of light in the process. When
much of the hydrogen has been used up the star expands
to its current red supergiant phase and it is now believed
to be fusing helium into carbon. Fusion continues through
several phases, and the star ends its life as a supernova.
In a supernova, the star's core collapses, then rebounds. A
massive shock wave moves through what's left of the star's
materials and we see a supernova.
The star currently varies in brightness by 1.5 magnitudes
and this variability indicates some instability in the star and
tells us quite a bit about what's going on internally with the
Shallow Sky Object of the Month
The Garnet Star
The location of the Garnet Star
from TheSky v6
star. Stars such as Mu Cep (the Bayer designation) are
called 'Small Amplitude Red Variables'.
There are other red variables that you can enjoy, one
of which has been written about in this series -- Hind's
Crimson Star. This one's in Lepus, just south of Orion,
so look for this one later in the year.
Other examples of SARV's are:
Betelgeuse - Alpha Ori. Most of us don't think of this
star as a variable, but it is.
R Lyr - north of the main part of the constellation
W Cyg

Joe at Scope.png October is here, and that means the weather should start to be a little cooler (maybe), night time comes a little earlier, and more importantly, fall star party season is upon us!  As I write this message, the UBarU star party was held just a few weeks ago, the Okie-Tex Star Party is happening this upcoming week, and in a month, the Eldorado Star Party will be in full swing.  For many of us, it’s a great time to get away under dark skies with many other kindred spirits to observe, take astrophotographs, enjoy great speakers, and otherwise enjoy the time away from the hustle-and-bustle of the big city.

For many people, the lead-up to their first “real” star party can be a bit of a nervous time. “What if my gear malfunctions?”  “What if I forgot a critical piece of equipment and now, I’m hundreds of miles from home?”  Or, perhaps the most intimidating thought of all, “what if I’m the one person who happens to ruin everything by committing the dreaded light violation?”

Star parties can be a bit overwhelming the first time you visit one.  The first time I visited the Texas Star Party, there were hundreds of other astronomers there, all seemingly more knowledgeable about astronomy than I was, and all with much better telescopes than what I lugged out to Fort Davis (this is certainly an exaggeration, but that’s how I felt the first time).  The terrain is dusty, the air is dry, and if the animals around there don’t kill you, the plants certainly seem like they will.

But there’s nothing quite like that first time under Bortle-1 or Bortle-2 skies, where everything is so dark, you can’t even make out the Big Dipper because it’s lost in a sea of stars.  Where the Messier objects you struggle to find with a small telescope or binoculars in Houston seem to “pop” with the naked eye just by looking in that direction.  Or where the fine details of a galaxy arm just look that much more well-defined without the extraneous light pollution that we deal with here every night.  More than this, though, there’s nothing like having that perfectly clear night under the stars that compels you to observe until the sun comes up with friends who are just as excited as you to be observing shortly before the crack of dawn.

For me, it’s that last item that makes these star parties special.  The camaraderie with other fellow astronomers on those dark nights, the sharing of views through an eyepiece, and the knowledge that is gained from others just can’t be beat.  It’s what draws me to these star parties over and over, and what makes our own dark site in Columbus a special place.  For those of us who love to learn by “doing,” these events are our opportunity to become better astronomers.  If you have an opportunity to visit one of these star parties, I highly encourage you to do so.  And if you can’t, you’re getting much of the same experience at our dark site.  Get your dark site certification done and visit at the next opportunity.

To all of you headed to Okie-Tex, the Eldorado Star Party, or to our dark site - happy photon hunting!

Title: Night Sky Network logo - Description: Logo for the NASA Nigth SKy Network featruing an adult pointing upwards at the night sky as a child observes with a telescope.This article is distributed by NASA Night Sky Network

The Night Sky Network program supports astronomy clubs across the USA dedicated to astronomy outreach. Visit to find local clubs, events, and more!

Weird Ways to Observe the Moon

David Prosper

International Observe the Moon Night is on October 16 this year– but you can observe the Moon whenever it's up, day or night! While binoculars and telescopes certainly reveal incredible details of our neighbor’s surface, bringing out dark seas, bright craters, and numerous odd fissures and cracks, these tools are not the only way to observe details about our Moon. There are more ways to observe the Moon than you might expect, just using common household materials.

Put on a pair of sunglasses, especially polarized sunglasses! You may think this is a joke, but the point of polarized sunglasses is to dramatically reduce glare, and so they allow your eyes to pick out some lunar details! Surprisingly, wearing sunglasses even helps during daytime observations of the Moon.

One unlikely tool is the humble plastic bottle cap! John Goss from the Roanoke Valley Astronomical Society shared these directions on how to make your own bottle cap lunar viewer, which was also suggested to him by Fred Schaaf many years ago as a way to also view the thin crescent of Venus when close to the Sun:

“The full Moon is very bright, so much that details are overwhelmed by the glare. Here is an easy way to see more! Start by drilling a 1/16-inch (1.5 mm) diameter hole in a plastic soft drink bottle cap. Make sure it is an unobstructed, round hole.  Now look through the hole at the bright Moon. The image brightness will be much dimmer than normal – over 90% dimmer – reducing or eliminating any lunar glare. The image should also be much sharper because the bottle cap blocks light from entering the outer portion of your pupil, where imperfections of the eye’s curving optical path likely lie.” Many report seeing a startling amount of lunar detail!

You can project the Moon! Have you heard of a “Sun Funnel”? It’s a way to safely view the Sun by projecting the image from an eyepiece to fabric stretched across a funnel mounted on top. It’s easy to make at home, too – directions are here: Depending on your equipment, a Sun Funnel can view the Moon as well as the Sun– a full Moon gives off more than enough light to project from even relatively small telescopes. Large telescopes will project the full Moon and its phases, with varying levels of detail; while not as crisp as direct eyepiece viewing, it’s still an impressive sight! You can also mount your smartphone or tablet to your eyepiece for a similar Moon-viewing experience, but the funnel doesn’t need batteries.

Of course, you can join folks in person or online for a celebration of our Moon on October 16, with International Observe the Moon Night – find details at NASA has big plans for a return to the Moon with the Artemis program, and you can find the latest news on their upcoming lunar explorations at

Four-photo mosaic, starting with the image of a hand holding a Sun Funnel in the bottom left; top left is a refractor telescope in the snow with a Sun Funnel showing the Sun; top right is a large Dobsonian telescope with a Sun Funnel; bottom right is a ghostly image of the Moon projected onto a Sun Funnel.

Sun Funnels in action! Starting clockwise from the bottom left, a standalone Sun Funnel; attached to a small refractor to observe the transit of Mercury in 2019; attached to a large telescope in preparation for evening lunar observing; projection of the Moon onto a funnel from a medium-size scope (5 inches).

Safety tip: NEVER use a large telescope with a Sun Funnel to observe the Sun, as they are designed to project the Sun using small telescopes only. Some eager astronomers have melted their Sun Funnels, and parts of their own telescopes, by pointing them at the Sun - large telescopes create far too much heat, sometimes within seconds! However, large instruments are safe and ideal for projecting the much dimmer Moon. Small telescopes can’t gather enough light to decently project the Moon, but larger scopes will work.

by Jim King

We have evidence that Messier may have been in poor physical condition during his later life. In 1802, Herschel visited the 72 year-old Messier in Paris, writing in his diary that Messier had “complained of having suffered much from his accident of falling into an ice cellar – an accident that had occurred two decades earlier.  Messier had also lost his wife and suffered from failing eyesight.  Although he continued to make the occasional observations, the climb up the octagonal tower to his telescopes must have also become arduous to his weary bones, especially on cold, damp nights.


(I can relate)


(An important jargon jogger:  Messier uses the descriptive term “nebula” frequently since he was frequently using a 3.5 inch telescope which had difficulty resolving dim stars.  It appears that he thought “nebulae” were not gas clouds, but simply unresolved star clouds.  Therefore, in our descriptions, we must mentally separate Messier’s “nebulae” from the real thing.  He does differentiate nebulosity from luminosity.)

M2 Globular Cluster (2 easy) *

In the fall, the vast summer Milky Way slips slowly into the western horizon after sundown.  Hours will pass before mighty Orion and other bright winter constellations rise in the east.  Looking overhead, we now peer straight out of the galaxy – away from the crowded stellar cities of the Milky Way’s arms into the suburb of stars whose residents include some of the most inconspicuous constellations in the night sky; chief among them Aquarius, the Water Bearer.  It is largely indefinable, and its faint stars must compete with light pollution.  Nevertheless, Aquarius contains a secret treasure well worth hunting for   - the spectacular globular cluster M2. 

Jean-Domonique Maraldi (1709-1788) first spied this “nebulous star” from Paris on September 11, 1746, while searching for Cheseaux’s comet.  Maraldi called it “very singular” in that he could not resolve any star within it, nor within the entire telescopic field.

Messier independently chanced upon this object on September 11, 1760.  M2 is certainly a marvel.  This 175-light-year-wide swarm of 150,000 stars is replete with yellow and red giant stars about 13 billion years old.

Messier note: (Observed September 11, 1760) Nebula without a star in the head of Aquarius.  The center is bright, surround by circular luminosity; it resembles the beautiful nebula that lies between the bow and the head of Sagittarius. 

NGC note: Very remarkable globular cluster, bright, very large, gradually much brighter toward the middle, well resolved into extremely faint stars.

Data:     Messier 2 aka NGC 7089

                           Con: Aquarius                                             Mag: 6.5

                            RA: 21h33.5m                                             Dec: -00.49

                            Dist: 37,500 ly

M15 Globular Cluster (2 easy) *

Nearly the twin of M2 in Aquarius, this glittering gem in the winged horse Pegasus is one of six beautiful globular star clusters brighter than 7th magnitude that grace the northern sky.  The great Pegasus Cluster, M15, can be spotted without difficulty as a “fuzzy star” with the unaided eye, lying just 4 degrees northwest of the of the topaz 2nd magnitude star Epsilon Pegasi.

Messier notes: (Observed June 3, 1764) Nebula without a star between the head of Pegasus and that of Equuleus.  It is circular and the center is bright.

NGC notes:  Remarkable, globular cluster, very bright, very large, irregularly round, very suddenly much brighter in the middle, well resolved into very faint stars.

Data:     Messier 15 aka Great Pegasus Cluster aka NGC 7078

                           Con: Pegasus                                               Mag 6.3

                           RA: 21h30.0m                                             Dec: +12.10

                           Dist.: ~33,900 ly

M30 Globular Cluster (2 easy) *

M30 is a fairly large globular cluster with a few hundred thousand stars splashed across 90 light-years of space.  We see it whizzing away from us at 115 miles per second.  M30 is one of the Galaxy’s most extremely metal-poor globular star clusters, with each of its members, on average, containing about 1/186 as much metal per unit of hydrogen as the Sun.  The cluster has an integrated spectral type of F3 and an estimated age of 13 billion years. 

Shining at magnitude 6.9, the moderately condense glow is surprisingly obvious under a dark sky through 10 x 50 binoculars.  Visually compressed, M30 has a tiny core inside a 12’ globular haze, though only about half that size appears dominant through the telescope.  Despite the object’s brightness, low power does not resolve it at all.    

Messier notes: (Observed August 3, 1764) Nebula discovered below the tail of Capricornus, close to the sixth magnitude star Flamsteed 41.  It is difficult to see with a simple 3.5 foot refractor.  It is circular and does not include any stars.

NGC note: Remarkable, globular cluster, bright, large, little extended, gradually, pretty much brighter in the middle, stars from 12th to 16th magnitude.

Data:     Messier 30 aka NGC 7099

                           Con: Capricornus                                        Mag: 6.9

                           RA: 21h40.4m                                              Dec: -23.11

                           Dist: ~26,400ly

M72 Globular Cluster (3 detectible) *

M72 is Messier’s faintest globular.  At magnitude 9.2 and just 6’ in apparent diameter, this globular is easy to pass over.  Look for a 9th magnitude “double star” separated by 5’ – the eastern component is, in fact a star; the western component is M72.  Once found, use moderate magnification to enlarge the cluster’s disk.

One of the reasons M72 appears so feeble is its distance; the cluster lies about 55,000 light-years from the Sun and 42,000 light-years from the galactic center.  Yet, in true physical extent, it spreads across about 110 light-years of space.

Messier notes: (Observed October 4, 1780, sort of) Messier was unable to clearly identify this object.  His assistant M. Mechain spotted it on the night of August 29, 1780. 

NGC note: Globular, pretty bright and large, round, much compressed in the middle, well resolved.

Data:     Messier 72 aka NGC 6981

                           Con: Aquarius                                             Mag: 9.2

                           RA: 20h53.5m                                              Dec: -12.32

                           Dist: ~55,400 ly


* Sky Tools offers an observability scale of 1 – 6, with 1 being “Obvious” and 6 being “Very Challenging”.  The particular rating scale I use is based on a Celestron SCT 8 Evolution telescope at the HAS dark site on a moonless night.


Ex astris, scientia, y’all!

Jim King

Field Trips and Observing Chair

Want more? Check out the HAS website under “Programs”/Messier Challenge/HAS 45


By: Steve Goldberg

Asterism: a grouping of stars that form a recognizable pattern.
Constellation: Cassiopeia
Right Ascension:  03h 27m 00.0s
Declination: +71° 50' 00"
Magnitude: 7 to 8
Size: 1.5 Degrees                            

This month’s Asterism is called Kimble’s Kite or the Kite Cluster. It is on the border of Cassiopeia and Camelopardalis.

To locate this grouping, use Delta δ and Epsilon ε CAS as pointers to Gamma γ CAM.

Here is a detailed finder chart with more stars between Cassiopeia and Camelopardalis.





Here is a picture showing the kite pattern. One corner is the star 15 CAS, also known as Kappa κ CAS.

Since the object is about 1.5 degrees across, use your lowest power eyepiece and also see if it is in your finder

Photo courtesy of “Ugly Hedgehog® - Photography Forum”, user Jimh123.


Novice Presentation - via Zoom

Event Date

            “Star and Galaxy Hopping.

           with Justin McCollum

One of the key skills that a new astronomer needs to learn is how to navigate the night sky in order to find objects of interest. Long before the advent of GoTo technology, astronomers relied on good star charts and a technique called star hopping to get then where they wanted to go in the sky. At times, when brighter stars are not available, such as toward the Galactic poles where most galaxy clusters are found, it can become convenient to use known galaxies as signposts in the sky.

Justin will describe how star hopping and galaxy hopping is done, what to look for in a star chart, and other tools you can use to make your exploration of the night sky successful and enjoyable.

Speaker Bio: Justin McCollum is a long time member of HAS and is on the staff of Lamar University where he is the Physics Laboratory Coordinator.

To Register for Zoom Meeting: Since we're all practicing safe social distancing, we have decided to bring our speaker to you virtually through the Zoom online meeting platform! You must register for this presentation in order to attend. You may do so by using the link below:

Please watch your email, as you should also receive an email inviting you attend. The email will include any up to date changes (if any) on meeting times etc. You may also register using the link in the email, however it is only necessary to register once.  

We'll have the online chat feature available to us during the talk, and once the presentation is over, we can open up the audio lines for more questions.  I'm excited that this we're able to get together in this fashion, and I hope you can join us then.  We hope to see you online with us on Thursday evening November 4th!