It has been a while since my last sidewalk astronomy experience. Seeing how I was going to write up an abbreviated version for Orion Telescopes Show and Tel contest, I decided to put up the full version of my prose here on my blog. I do enjoy the occasional “street” session to educate the masses about our fantastic hobby. So without further ado, here is the full version….
I have always tried to promote our hobby of stargazing to the masses. I have a couple of colleague that have more than a passing interest in looking up. Being in Brisbane, QLD, Australia has its perks. I have been stargazing here since the late 90’s and have seen the sky get progressively worse. The milky-way used to be a lot more structured, even from my apartment balcony in suburbia. Back then I could go down to magnitude 5.7 easy and hunt galaxies brighter than magnitude 10 with my C6. I have even spied M33 in my 15x70 on excellent transparency winter nights. These days the best I can manage is 5.5 under similar conditions (still much better than at my current abode in Culver City, CA where the best I can manage is 5.2). The milky-way is still visible in the direction of Sagittarius-Scorpius region, although devoid of all structure, and the SMC and LMC can barely be made out. One has to know where to look.
I have organized several sessions in the past, mostly using my Orion 80ST on a photo tripod, and my old beat up Celestron C6 6”f/5 newtonian (mostly involving two or three close friends). I usually organize such sessions closer to the southern austral winter as there are many brighter things to look at. Also I usually choose public parks such as Robertson’s Park in Indooroopilly, a site also used by the Brisbane’s Suburban Astronomers group, and Mount Cootha, used by the Brisbane Astronomical Society. I have successfully “infected” two of my non astronomer friends to take up the hobby, with one getting just a 76mm Alt-Az scope not unlike the 3” Orion Spaceprobe, and the other a 6” f/5 Eq Newtonian. Both have just a passing interest and occasionally look up at the planets. Guess you have to start them somewhere right?
This time however I had a much bigger group, approximately 10 people in total. I put a note up on the whiteboard at work and have been talking it up all week!!!!! Everyone knows I am the labs astro geek. I chose a site not too far from home and work, a site used frequently by my then lab for Melbourne Cup day picnics, Perrin Park in Taringa, Brisbane, QLD. I have also used that site extensively since moving to Taringa on nights I want to use the 10” f/5, and I am not at my society’s dark sky site in Leyburn. The dob is way to big to be carried up three flights of stairs or to be used in my apartment balcony. My target this time was to get the 10” f/5 GS out, in addition to my trusty C6 6” f/5, Orion StarBlast 4.5” f/4 and my 20x80.
This time of the year (mid September) Orion is still up for a bit, and the winter milky way rises not much later. First up was the seven sisters in Taurus. I think everyone agreed that the views were much better in the 20x80’s, with the StarBlast coming a close second. I challenged them to visual test to see how many Pleiads they could spot with the naked eye. Most could see 6. Then we moved onto M42, the Orion Nebula. This one drew gasp through the 10” with many commenting that the nebula looked distinctly “greenish”. They also liked the open flower impression. This also allowed me a chance to start explaining about young open clusters (i.e. the Pleiades) and how stars form from collapsing gas in nebulae (they also liked how nebulae is the latin word for cloud ;)
Taking it from the top, I began talking about forming stars, galaxies (sadly the skies were not nearly good enough to show them any bright galaxies…I did try NGC 5128, Centaurus A later but no one could see it…I find beginners generally find it hard to see galaxies, even the brighter ones!!!), globulars (everyone was impressed with Omega Centauri, M22 and all could make out individual stars in the 10” and the 6” at high magnification). It was also a good time to explain the difference in light gathering since I had a good representation of scopes (4.5”, 6”, 10”) as well as the effects of light pollution and the use of ultra high contrast (UHC) nebula filters. Most liked the views of open clusters better in the StarBlast and in the 20x80 (especially views of open clusters such as the Pleiades, M6 and M7 in Scorpius…they commented that they could make out the butterfly shape better in these) and the numerous star spangled fields around Eta Carina Nebula.
Throughout the night, I showed them more examples of gaseous nebulae. They got to compare and contrast M42, the Orion Nebula versus Eta Carina Nebula. Most of them agreed that Orion was easier to look at, but Eta Carina showed more character due to dark lanes, that were emphasized much better with the UHC filter. But it wasn’t these two celestial showpieces that stole the show, it was the swan/omega nebula (M17) in the northern reaches of Sagittarius. When some could not quite make out the shape, one of my female colleagues dropped onto the grass scrunched herself up to make a swan shape……definitely the highlight of the night!!!!!! Finished off the night right at the end of a stars life and showed them examples of some of the skies best planetary nebulae, M57, the Ring Nebula in Lyra and M27, the Dumbbell Nebula in Vulpecula. My colleagues loved my association of M57 to Homer’s doughnut, but they could not quite understand why M27 was called the Dumbbell Nebula. Apple-core or football nebula was more appropriate ;) As some of them put it, without the UHC filter, it looked like someone took two bites on either side of the football. Overall a fantastic night out with great company. Although I really enjoy my quiet moments under pitch black skies, I occasionally yearn for the companionship that only sharing the universe with some other like people can provide. This is also a good way to educate people on why we must preserve our night skies for future generations to come…….
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