Friday, February 28, 2020

Improv at the Impromptu

Last Saturday was blessed with a dome of high pressure over the mid-Atlantic, bringing transparent but frigid skies. Despite the chill Chris Miskiewicz announced he'd open Alpha Ridge for a HAL Impromptu star party. As soon as he called it I fired up Telescopius and elected galaxy NGC 2841in UMa as my primary target for a photography session. If I could hold out against the cold I'd also attempt a wide field of Messier duo of M97\M108. Little did I know that despite my best efforts of being prepared for my evening under the stars I'd need to circumvent a variety of unexpected challenges!

I started packing up the equipment into the Rogue about 5pm. First in was the Orion Atlas EQ mount - but wait! What the heck!? One of the tripod leg tips was missing! I spent 10 minutes scouring the area where I usually observe from home and in the garage where the tripod is stored but no luck. I decided that I could still make it work for the evening by extending the affected leg a bit. Improvisation #1.



Made it to Alpha Ridge as twilight was fading fast and the temps dropping. I transferred the equipment to my observing spot and roughly aligned the mount on the North Star. Turning on laptop and the PoleMaster camera I thought I had Polaris in the field, but soon realized it was an imposter. Nudging and bumping the mount this way and that brought no other suitable candidate star onto the screen, so finally I resorted to taking the camera off and sighting it through the shaft as was my custom prior to PoleMaster. This improvisation allowed me to get Polaris onto the screen when I reattached the camera - all at a cost of time. Finally, about an hour after my arrival I was ready to target NCG 2841 and begin taking my series of 30 second exposures.

I popped on the Telrad and reached for its On lever, only to find it was already on. Nooo! I cranked up the rheostat in hopes that maybe it had happened when loading the Telrad into the car but the poor batteries had no juice left to give me. Sigh - and no spare batteries with me. Alright then - we'll do it using the Vixen scope's finder. Improvisation #3.

I get the Tiger Eye galaxy in the eyepiece and begin to attach the Canon and establish its WiFi to my tablet. Boom - my Orion red headlamp I'm wearing shuts off. Did I bump it? No, apparently I'm having the worst dead battery night I've ever had. Fortunately for this bump in the road I did at least have a hand held red-light flashlight that I dig out from my observing toolbox. With improvisation #4 I'm finally connected and snapping photos.

Sketch NGC 2814


The allure of these clear February skies keep me from being bored while firing off round after round of 30 second exposure. I drink in the showy winter constellations: Orion and his dogs, the Twins, the Bull - all old friends who have crested and are riding the night tide to the western horizon. Over the dome of HALO the Big Dipper stands on its handle as if to vault itself high overhead. Leo climbs his way up the eastern sky as the subtle Hydra crawls beneath his feet. No matter how high-tech the gadgets become and what they can do, there is still something in the amateur astronomer's very being that finds joy in taking in a starry sky with nothing more than one's eyes.

By 9:15 p.m. the cold is beginning to win - I clearly do not have the perseverance to start a new session targeting the Owl Nebula and nearby galactic neighbor M108 - that will need to wait for another spring evening. I take my final 30 second light shot and go to get my home-made "light box" that I use to take my flats. Arrghh - are you kidding me!? I guess with the distraction of finding my peg-legged tripod I neglected to pack it. Think, think, think - how can I get a diffuse light source for these flats? I wonder if - maybe I can find a way to make my Samsung 10" tablet display an almost completely white screen? Can I find some web site or document to meet my need? A quick Bing search and - by Jove - there it is! The "White Screen Page" is exactly what I need for Improvisation #5. I load the page on my tablet and hold the tablet over the Vixen 80sf dew cap and rattle off my flat shots. Wow, that improvisation worked great!

Before I pack it in I take a few minutes to do a visual observation. At 60x in the 80mm refractor the galaxy is readily seen as a soft, elliptical glow running more or less in a N-S orientation. There's no core visible but the star field is pleasant with a tight, white double at the southern edge of the field competing for one's attention - the sort of pair whose symmetry of magnitude and coloration make it stand out. There'd be no hope of seeing the subtle light of this distant island universe from my driveway, so I linger a few moments to enjoy the benefit of Alpha Ridge's skies.

The next day I do some preliminary work with the image files in DSS and PixInsight. It's always a bit like Christmas morning when you open up that stacked photo to see what you have. The result is decent for a first pass but I think that there's more in there that can be teased out - if only I knew the intricacies of PixInsight better. The good news is that with the data in hand and safely dropped onto the cloud storage, NGC 2841 can await a cloudy night in the future to have its details extracted from the hour's worth of exposures. 
NGC 2841, the "Tiger's Eye" galaxy
Oh - and that eye-catching double? Turns out that's STF (Struve) 1341, a near equal 9th magnitude pair with a separation of 20" and sun-like spectral class G5. And to top it off, the preceding one of this E-W aligned pair [HD 80606] actually has an exoplanet associated with it weighing in at about 4 Jovian masses and whipping about the star once every 111 days. 80606b also sports an amazing orbital eccentricity of e=0.927 - check out the diagram below from NASA website "Earth Observatory" to get a sense of how elongated the orbit is (Pluto is e=0.25 for comparison). As Spock would say, "Fascinating..."

Orbital Eccentricity

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