OR: Meadowlark Lemon

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itsmar...@gmail.com

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Jan 17, 2021, 5:12:55 PM1/17/21
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I was out last night for a short session splitting doubles in Cassiopeia.  A very enjoyable session, with easy hops to all targets. I was using 9x50 finder to get to bright stars below unaided visibility threshold.  Transparency was reasonable, perhaps 3/5, but seeing was quite good at 4/5 or better for the 2 hours I spent.  Finished up looking at the M42 region of Orion after my neighbors backyard weekend hanging light party grid went on (serving absolutely nobody). I found one aspect of M42 particularly fascinating, which I'll get to after notes on the doubles I observed.  Even though it was a shortened night observing, it was wonderful being back outside at the eyepiece in Spring-like conditions. My scope is still set up with possibility of reasonable skies tonight.

Telescope: 10" f/5.6 Dob on an Equatorial Platform.  Oculars and accessories: 20mm, 12mm, 7mm, 4.8mm, 3.8mm, 2X Barlow, 4" aperture mask, Quickfinder, 9x50 optical finder.

V779 Cas    Cas    sao 4550    02 02 09    +75 30 08    STF 185 AB    6.77    8.58    1.1    9
20mm showed nice wide pair with striking blue primary and dimmer reddish companion.  3.8mm shows blue mag 6 primary with 2 magnitude dimmer companion reddish at PA 10. Very tight split.

Cas    sao 4776    02 56 11    +72 53 10    STF 312 AB    8.16    8.92    1.7    47
Using a 4.3mm, this was a clean split of gold-white tight pair with a clean split, secondary near 0 PA maybe half mag dimmer.  Nice wider view with nearby star comprising possible trio.

48 Cas    Cas    sao 4554    02 01 58    +70 54 25    BU 513 AB    4.65    6.74    0.5    355
At 604X using 2X Barlow, 3.8mm and aperture mask made which made the primary very round with concentric rings. Barely split white pair with primary trailing, 2 mag difference.

Cas    sao 12530    02 58 07    +69 11 36    STF 317    7.93    9.82    4.1    83
Nice easy split in 4.8mm with blue-white primary preceding a very dim deep blue companion.  Close but easy.  Nice additional star dimmer than primary trials the pair comprising a nice view.

Iot Cas    Cas    sao 12298    02 29 04    +67 24 09    STF 262 AB    4.63    6.92    2.6    227
This pair almost splits in the 20mm, but at 7mm shows a beautiful trio featuring a gold white primary at mag 4.5 perhaps 2 mags brighter than blue-white companion close to its southwest.  Trailing to the east is a somewhat red third member with nearly equal mag to secondary.  This is also a very ice easy naked-eye find.

Cas    sao 12298    02 29 04    +67 24 09    STF 262 AC    4.63    9.05    6.7    117
Included in Iota Cas.

Cas    sao 12298    02 29 04    +67 24 09    CHR 6 Aa,Ab    4.63    8.48    0.7    20
Using the 2X Barlow, 3.8mm and aperture mask, the companion showed 4 mags dimmer than the primary yet easily viewed directly west with plenty of split! I attribute the ease to the aperture mask.

Conclusion of the night is that the aperture mask addition on tight doubles in a complete winner.  The clean roundness of the stars with concentric rings is stunning.  Diffraction spikes from a spider removed, it is much easier to see the closest doubles or widest magnitude deltas. The mask is an easy-on/easy-off tool.

As I mentioned, I turned to the Orion Nebula for a peek once the neighbors "car-lot lights" told me it was time to button things up.  I was enjoying the grey tones of the internal wings with a 20mm and 2X Barlow.  It occurred to when glancing at the Trapezium to count stars.  A, B, C, D..... E........ oh yeah, F!  But something else caught my eye.  Colors.

I had never noticed the astonishing yellow of the Trap's A member.  Stunning!  Its tone is so intensely prominent it simply commanded the view.  Literally stunned.  I stared wondering why I'd never noticed it before.  I must have views this group a hundred times.

So, what gives?  Is my eye more trained for star colors after observing so many doubles?  There is a tremendous range.  Sometimes the colors are confusing, looking red, then a moment later blue or purple.  Especially true in the dimmest companions.  Or, as I've aged has my eye yellow so much that the Trap's A member is now "showing off", enhanced so to speak by the changes in my eye?  Probably both.

So I went inside thinking about this most outstandingly colored star.  Its not "mellow yellow".  I couldn't come up with an apt description.

Today, out early hiking in the Coyote Valley with binoculars, a spectacular bird grabbed my attention because of its song and then the intense color.  The Meadowlark. Its yellow colored chest was stunning.  What a star!  It's literally a lemon yellow.

The Trapezium's "A" star tremendous color matched that bird - Meadowlark Lemon,. An outstanding star I'll never forget.  Cue Sweet Georgia Brown..... going to watch Mr. Lemon highlights on YouTube now, and look at that star again tonight in my telescope.

Steve Gottlieb

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Jan 17, 2021, 9:23:11 PM1/17/21
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I’ve logged several of these in the past — comments below.

> On Jan 17, 2021, at 2:12 PM, itsmar...@gmail.com <itsmar...@gmail.com> wrote:
>
>
> I was out last night for a short session splitting doubles in Cassiopeia. A very enjoyable session, with easy hops to all targets. I was using 9x50 finder to get to bright stars below unaided visibility threshold. Transparency was reasonable, perhaps 3/5, but seeing was quite good at 4/5 or better for the 2 hours I spent. Finished up looking at the M42 region of Orion after my neighbors backyard weekend hanging light party grid went on (serving absolutely nobody). I found one aspect of M42 particularly fascinating, which I'll get to after notes on the doubles I observed. Even though it was a shortened night observing, it was wonderful being back outside at the eyepiece in Spring-like conditions. My scope is still set up with possibility of reasonable skies tonight.
>
> Telescope: 10" f/5.6 Dob on an Equatorial Platform. Oculars and accessories: 20mm, 12mm, 7mm, 4.8mm, 3.8mm, 2X Barlow, 4" aperture mask, Quickfinder, 9x50 optical finder.
>
> V779 Cas Cas sao 4550 02 02 09 +75 30 08 STF 185 AB 6.77 8.58 1.1 9
> 20mm showed nice wide pair with striking blue primary and dimmer reddish companion. 3.8mm shows blue mag 6 primary with 2 magnitude dimmer companion reddish at PA 10. Very tight split.

I viewed this one with a 6” mask on my 18” from the Sierra Buttes! — Cleanly resolved at 323x with a 6-inch mask or at full aperture in moments of better seeing. The mag difference appears ~2.0 mag. When entering these notes, I discovered the double is close following the faint open cluster, Berkeley 8. I viewed the cluster afterwards, which showed a scattered dusting of very faint stars.

> Cas sao 4776 02 56 11 +72 53 10 STF 312 AB 8.16 8.92 1.7 47
> Using a 4.3mm, this was a clean split of gold-white tight pair with a clean split, secondary near 0 PA maybe half mag dimmer. Nice wider view with nearby star comprising possible trio.

In my 14.5” — his 1.7" pair was barely resolved cleanly at 158x. Easy "wide" split at 264x. A mag 10 star (C component) is at a very wide 43”.

> Cas sao 12530 02 58 07 +69 11 36 STF 317 7.93 9.82 4.1 83
> Nice easy split in 4.8mm with blue-white primary preceding a very dim deep blue companion. Close but easy. Nice additional star dimmer than primary trials the pair comprising a nice view.

Very nice 4" pair at 158x with a moderate delta. Resolved even at 122x.

> Iot Cas Cas sao 12298 02 29 04 +67 24 09 STF 262 AB 4.63 6.92 2.6 227
> This pair almost splits in the 20mm, but at 7mm shows a beautiful trio featuring a gold white primary at mag 4.5 perhaps 2 mags brighter than blue-white companion close to its southwest. Trailing to the east is a somewhat red third member with nearly equal mag to secondary. This is also a very ice easy naked-eye find.

First resolved 42 years ago in a 6”! Good color contrast, excellent triple in steady conditions at 165x or higher.

> As I mentioned, I turned to the Orion Nebula for a peek once the neighbors "car-lot lights" told me it was time to button things up. I was enjoying the grey tones of the internal wings with a 20mm and 2X Barlow. It occurred to when glancing at the Trapezium to count stars. A, B, C, D..... E........ oh yeah, F! But something else caught my eye. Colors.
>
> I had never noticed the astonishing yellow of the Trap's A member. Stunning! Its tone is so intensely prominent it simply commanded the view. Literally stunned. I stared wondering why I'd never noticed it before. I must have views this group a hundred times.

I’ve never logged the “A” component as yellow, but I have logged its fainter companion “E” as distinctly orange in my 24"! But colors are so subjective and subject to contrast effects.

Steve

itsmar...@gmail.com

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Jan 18, 2021, 6:33:51 PM1/18/21
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Hi Steve,

Thanks for the feedback.  I sure had a good time.  Last night on the other hand was 45 minutes of trying to maneuver around the neighbor's light trespass and trouble star hopping in the openness between Cassiopeia and Camelopardalis.  I threw in the towel early.

I think Iota Cass is an unknown gem, and so easy to get to.  Amazing your observation goes back to my pre-kids days.  Probably yours too.

I was so surprised at how I saw the bright star in the Trapezium.  I've never seen such a rich color in a yellow star.  Even more amazing is how many times I've seen it as white. I hope to get another look once the winds settle down.

I'm laughing at all the typos and nasty autocorrect mistakes appear in my posting.  I need to wait until I've had several cups of coffee before writing.

Steve Gottlieb

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Jan 18, 2021, 6:58:01 PM1/18/21
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Speaking of Orion, it’s probably my favorite constellation for double stars.  Oh, yeah, I heard there’s a nebula somewhere in there, also ;-)

Anyways, it’s amazing how many bright, fairly close pairs the constellation contains.  Here’s a list (I just compiled this minute) of 22 bright double stars that are between 0.6" and 2.9”.  I've observed most of these multiple times (pun intended), though several observations were made 12 years ago, so some listed separations may be slightly off now.

Steve

14 Ori = STT 98 = ADS 3711
05 07 52.9 +08 29 54
V = 5.8/6.7; Separation 0.8"

STF 643 = ADS 3712
05 07 55.0 +08 24 09
V = 9.6/9.6; Separation 2.5"

STF 652 = ADS 3764
05 11 45.3 +01 02 12
V = 6.3/7.4; Separation 1.7"

STT 517 = ADS 3799
05 13 31.6 +01 58 04
V = 6.7/7.0; Separation 0.65"

Bu 190 = ADS 3927
05 20 24.1 -08 01 47
V = 8.1/8.5; Separation 0.6"

Eta Ori = ADS 4002
05 24 28.6 -02 23 50
V = 3.6/5.0; Separation 1.6"

STF 708 = ADS 4012
05 25 11.3 +01 55 26
V = 7.7/8.9; Separation 2.8"

Psi2 Ori = 30 Ori = ADS 4039
05 27 03.4 +03 05 58
V = 4.7/10.3; Separation 2.7"

32 Ori = H I 25 = STF 728 = ADS 4115
05 30 47.1 +05 56 53
V = 4.4/5.7; Separation 1.4"

STF 726 = ADS 4113
05 30 51.7 +10 15 16
V = 7.9/8.6; Separation 1.2"

33 Ori = H I 22 = STF 729 = ADS 4123
05 31 14.5 +03 17 32
V = 5.7/6.7; Separation 1.8"

STF 734 = ADS 4150
05 33 07.3 -01 43 02
V = 6.7/8.2; Separation 1.6"

STF 743 = ADS 4176
05 34 43.2 -04 23 31
V = 7.7/8.3; Separation 1.8"

42 Ori = DA 4 = ADS 4187
05 35 23.2 -04 50 18
V = 4.6/7.5; Separation 1.2"

STF 757 = ADS 4234
05 38 06.5 -00 11 04
V = 8.0/8.3; Separation 1.5"

Zeta Ori = Alnitak = STF 774 = ADS 4263
05 40 45.5 -01 56 33
V = 1.9/5.0; Separation 2.2"

52 Ori = STF 795 = ADS 4390
05 48 00.2 +06 27 15
V = 6.0/6.1; Separation 1.0"

STF 851 = ADS 4726
06 08 04.4 +03 17 24
V = 8.9/9.5; Separation 2.9"

STF 849 = ADS 4730
06 08 44.5 +17 24 07
V = 9.1/9.5; Separation 0.9"

STF 848 = ADS 4728
06 08 44.7 +13 58 17
V = 7.9/8.6; Separation 2.5"

Ho 22 = ADS 4823
06 13 27.5 +10 14 52
V = 8.5/8.6; Separation 0.9"

Bu 1019 = ADS 4882
06 16 07.6 -02 52 56
V = 8.0/9.6; Separation 0.8"


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itsmar...@gmail.com

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Jan 19, 2021, 1:05:01 PM1/19/21
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Psi 2 Ori caught my attention in your list because of the wide magnitude difference.  What did you observe it with?  I checked Stelladoppie, and it shows the secondary brighter than your note by around 1.5 mags; 8.6 vs 10.3.  I wondered if it was a variable, which it isn't. The primary is, but a small range.

Speaking of doubles rich constellations, I recall sorting my list of maybe 2000 doubles by constellation, then counting them.  Some constellations are much richer than others - the rich ones must cross the (thick disk? of) Milky Way.  I was also stunned at the number of variables (or perhaps just novae) toward the center of the galaxy.

BTW... just found an interesting paired target.  Double stars Kappa (tight) and Iota (wide delta) Leporis, along with the 75 day variable RX Leporis right next to (naked eye) Iota.

Steve Gottlieb

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Jan 19, 2021, 2:59:11 PM1/19/21
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Psi 2 Ori caught my attention in your list because of the wide magnitude difference.  What did you observe it with?  I checked Stelladoppie, and it shows the secondary brighter than your note by around 1.5 mags; 8.6 vs 10.3.  I wondered if it was a variable, which it isn't. The primary is, but a small range.

There seems to be a large variation for the companion’s magnitude - Burnham’s Celestial Handbook called the pair 5 and 11 (delta ~6).  “The Sky Live” lists the magnitudes as 4.59 and 10.19 (delta = 5.6), but as you noted Stelladoppie says 4.6 and 8.6 (delta = 4).  I assume that obtaining accurate photometry on a fainter star in the glare of a much brighter one is very difficult.

Anyways, I’ve observed this large mag difference pair twice, back in 2004 and 2008.  Both times I used a 6” mask on my 18” Starmaster.  In 2004, I wrote I had a clean split and in 2008, I logged "fairly close but just resolved at 175x using the 6" mask and fairly easy at 225x.”

Steve
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