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Ships and Stars

SQM, XWAs and melting wires at Dark Sky Alpha...

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Bit of a struggle at times, but another great night overall with the 500p at 'Dark Sky Alpha', the darkest place I can get to within a reasonable night's drive from home and back.

Was armed with a shiny new SQM-L meter and three APM/Lunt 20/13/9mm 100 deg EPs. Happy days! (or nights)

At long last, I finally got to try out the Unihedron SQM-L meter to get some proper benchmarks. I was a little disappointed when it first said 21.62 during astro darkness, then increasing to 21.74, 21.78 and so on. By 11pm onwards, it consistently read 21.80-21.85 (!) the rest of the night with tests about every 20-30 minutes, and I’ve been there on what I would consider darker nights. 

So 21.80-21.85 on one night, versus the LP map which says 21.89-21.92. Works for me!

I absolutely love this spot when the wind is down… because it was very windy again much of the night, had to remove the truss shroud (again) to reduce windage and keep moving the van to help shield the scope from gusts, but it finally died down around 1:30am, though I was beat by that point, as I braved the half-empty shops yesterday and then cleared my wife’s office so she could work from home.

My biggest challenge - had a massive power wire meltdown from my leisure battery cable at the power socket end(!), don’t know what happened, think a strand of wire internally pierced the insulation and shorted, so I lost my alignment but fortunately didn’t damage anything and didn’t blow any fuses, though I wonder why not?? That’s what fuses are for! Hmmm...

I had to scratch my head for a solution and thought I would be manually driving the dob around trying to find tiny galaxies, but I ended up taking the executive decision to cut and splice the cable from my new dew heater controller into the alligator clamps for the leisure battery and a spare 12v socket, as the dew heater cable was marked red/black and I could be fairly sure I wasn’t reversing polarity in the field without a multimeter and fry the encoders! I did this the dark with a Stanley knife and a red LED, lost 30-45 minutes doing this and realigning just before midnight, but it saved the night and I kept my dark-adapted vision. Field expedient solution!

Observing at last

-Horsehead/Flame Nebulae were the first stops early in the evening (pre-electrical meltdown) to check seeing before they set – HH was initially a little confusing to hunt down as it is now rotated at a clockwise angle through the EP this time of night/year, but suddenly appeared very nicely with direct vision – 17.5mm Morpheus with Astronomik Hb filter worked best. Again. A good start, but lots more to visit.

-Seeing on M42 was initially abysmal and worrisome – I think it was due to a combination of atmospheric turbulence, too much mag and a still-warm primary from the van trip. M42 was just above the horizon which certainly didn’t help, but it looked like watching a candle melt through a waterfall, haha.

Things shaped up considerably as the mirror cooled and I moved to higher targets.

-Rosette Nebula – spur of nebulosity running off in the 4 o’clock position, clear as day. Could spend ages looking at this under dark conditions, so much to see. Love it.

-Hind’s Variable – used the 9mm APM 100 deg at 222x – excellent! A unique sight, even among DSOs.

-M1 – very good, but wouldn’t say I saw structure! Just a bright cloudy puff but plain as day.

-Bubble nebula – excellent, could make out a fair bit of detail in this.

-IC405 flaming star – excellent, best I’ve seen it. Nebulosity to me is not in your face bright, but quite extensive, the whole area seems to have a patchy glow of nebulosity of various magnitudes extending well away from the core and even beyond the FOV of the 20mm 100deg Lunt.

-Little Dumbbell – another best view, wonderful.

-Cocoon – yes? I think I can definitively say I got it this time. Popped right into view with the Hb and could tease out faint detail with averted vision. Very low on horizon.

Galaxies – this is where it gets tricky because there are so many in the EP under dark conditions. I almost need an A3 chart hanging next to the scope with all galaxies in a given area down to say Mag 15 or 16 and a pencil to tick off the ones I can locate.

-South of Markarian’s Chain – I lost count again. I am definitely seeing galaxies that aren’t in the S&T Atlas and some that aren’t on Uranometria, but despite being small, are excellent and directly visible. Must be PGCs/ARPs/Hicksons, though I don’t know much about these at all. Stellarium seems to show more than any other catalogue I know of, though I cannot say they are all on there. Again, mind-blowing.

Wow, there are a LOT of galaxies, says this novice... ;)

I really don’t know if I ever would be able to learn my way around many of these galaxy clusters by memory. A really, really good alignment is critical for saving time and frustration here, and the 20/13/9mm APM 100deg EPs are awesome to use both to find faint galaxies by virture of a wide FOV and also just optically. Glad I bought the 9mm, was going to skip it but it’s already proven itself. Only offers slightly more detail on small galaxies than the 13mm, but more engaging of course, as objects get larger (though not really brighter).

I then went to Ursa Major and NGC 3998, a 13.01 mag surface brightness galaxy in UMa that @Jetstream recently mentioned to me. Found that easily along with the smaller NGC 3990 and think there might be a tiny, and I mean tiny galaxy in between that went in and out of vision,  but could have been a very faint star. I then started following two more pairs of galaxies in the area, some on the fainter side, but all easily visible with direct vision. UMa is a whole new kettle of fish, I’m still trying to get my head around Virgo cluster!

Just wish I could definitively identify which galaxies I’m viewing – some are extremely faint and must be PGC/ARPs/Hicksons that are perhaps not frequently observed. Something I need to work on and be more organised, but time is limited.

Then onto M108, excellent, lots of detail visible last night in this large galaxy. Another best personal view.

M97 Owl Nebula (planetary nebula) - I’ve seen this a few times now this year,  but last night it was AMAZING. The ‘owl eyes’ were directly observable and the entire planetary nebula just popped out like a glow in the dark sticker. I dare say it was bright and impossible to miss.

I did a quick scan with the 15x70s once everything was packed, but was dog tired and had a long drive ahead.

Next time need to organise list better, but was just lucky to get away for a bit last night. 👍

IMG_20200318_234723411.jpg

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Really good investment in a Unihedron SQM-L Robert. Those are reassuringly V good readings. That is a canny bit of improvised DIY and in the dark. A substantial session exploring a wealth of deep sky subject. It is easy to become immersed and get lost in those galaxy groups. As you mention, Markarian's Chain provides definition and a profile to relate to those others, but yep your scope and sky condition, going deeper, yes a more specialised chart may be required.

Strange times indeed, at least for now this pursuit complies fully with the current social distancing measures.

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4 hours ago, Ships and Stars said:

I then went to Ursa Major and NGC 3998, a 13.01 mag surface brightness galaxy in UMa that @Jetstream recently mentioned to me. Found that easily along with the smaller NGC 3990 and think there might be a tiny, and I mean tiny galaxy in between that went in and out of vision,  but could have been a very faint star. I then started following two more pairs of galaxies in the area, some on the fainter side, but all easily visible with direct vision. UMa is a whole new kettle of fish, I’m still trying to get my head around Virgo cluster!

Excellent!

You should see 2 pairs plus a" lone" straggler + 3 PGC... I see 5 with my 15", no PGC.

PGC 37442,PGC 37341 and PGC 37532

You might need to try on the PGC, the 10 BCO will help.IMHO.

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1 hour ago, scarp15 said:

Really good investment in a Unihedron SQM-L Robert. Those are reassuringly V good readings. That is a canny bit of improvised DIY and in the dark. A substantial session exploring a wealth of deep sky subject. It is easy to become immersed and get lost in those galaxy groups. As you mention, Markarian's Chain provides definition and a profile to relate to those others, but yep your scope and sky condition, going deeper, yes a more specialised chart may be required.

Strange times indeed, at least for now this pursuit complies fully with the current social distancing measures.

Yes the unihedron puts to bed any ideas about the LP map being way out. I have squeezed 20.35 from home, but that's about it. I stopped and took readings along the way last night, popped my arm out the window at a traffic light (no cars around) and took a reading in a small nearby town - only 7.07!!

It's reassuring to see if a site is givig a good reading. 

I think Stellarium probably shows the most, but did print a paper close-up chart of the Virgo cluster that was in the appendix of the deep sky atlas.

I'm glad you were able to get out Iain! Frustratingly for me, it's clear again all night at the dark sky spot and no wind, but I'm shattered!

Might get the 300p out here at home though.

 

Cheers

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2 minutes ago, jetstream said:

Excellent!

You should see 2 pairs plus a" lone" straggler + 3 PGC... I see 5 with my 15", no PGC.

PGC 37442,PGC 37341 and PGC 37532

You might need to try on the PGC, the 10 BCO will help.IMHO.

Thanks Gerry! It's clear again tonight out at the dark site and virtually no wind, plus the 10mm BCO arrived this morning...but I'm shattered! A bit frustrating to run out of steam right now, but might get the 300p out here. 

I only jotted down some NGC numbers yesterday before I left so was ill prepared. Hectic yesterday, basically cleaned my wife's office out yesterday as they are locking up her work probably until summer! 

If I get a burst of energy, might head out of town a little, but a bit drained. Hoping to get my head around these galaxies a bit better before summer, but tonight is a tough one to miss! 

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21 minutes ago, Ships and Stars said:

Yes the unihedron puts to bed any ideas about the LP map being way out. I have squeezed 20.35 from home, but that's about it. I stopped and took readings along the way last night, popped my arm out the window at a traffic light (no cars around) and took a reading in a small nearby town - only 7.07!!

It's reassuring to see if a site is givig a good reading. 

I think Stellarium probably shows the most, but did print a paper close-up chart of the Virgo cluster that was in the appendix of the deep sky atlas.

I'm glad you were able to get out Iain! Frustratingly for me, it's clear again all night at the dark sky spot and no wind, but I'm shattered!

Might get the 300p out here at home though.

 

Cheers

That's it, when conditions are suitable, taking a frequency of readings is a good reference and indicator, particularly at varying stages of the night time period and comparing between different locations. Due to light pollution reflected off cloud and the nature of objects I was observing last night I didn't consider using mine at all. Those you took are exceptionally good readings though. It looks promising here tonight but I think I am at work tomorrow, though as with many things presently there is a degree of uncertainty. last night was OK, earlier I had a hastily arranged dentist appointment, some needed treatment, brought forward as they might have to close except for emergencies. My mouth still a bit seized up from injections, roaming around focused on looking at open clusters in the fresh air was therefore great. 

In terms of charts, I do not have this atlas; the Uranometria 2000.0 Deep Sky Northern Hemisphere; is this the version you use? More expensive compared to the All Sky version, with further extensive content gained in magnitude? 

 

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