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37 Carbon Stars (PDF version added)

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#1 Man in a Tub

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Posted 28 November 2012 - 01:35 PM

The attached file contains 36 carbon stars I have observed over several years. The list was assembled in SkyTools 3, exported and converted into an .xls file. The list is sorted by constellation [correction]. The additional columns in each row contain alternate identifiers. When observed, magnitudes have likely ranged from about 5th to almost 10th. Depending upon the faintness of their minima, some carbon stars cannot always be seen with binoculars. For example, V Hya eluded re-observation earlier this year.

The list is limited to that part of the sky I can observe.

There is an "improved" PDF version below in the thread.

Lots of fun.

Attached Files



#2 Mark9473

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Posted 28 November 2012 - 01:40 PM

Bookmarked! Thanks Todd.

#3 GlennLeDrew

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Posted 28 November 2012 - 02:03 PM

Back in '98 I downloaded Stephenson's carbon star catalog, and wrote a utility to export those I deemed visible in my 10X50s. I formatted the data so that it could be plotted by the DOS-based sky charting software, Deep Space. (At the same time, I did this for suitable bino doubles, too.) I then printed out a custom double star/carbon star atlas, and embarked on a quest, observing I don't know how many.

My favorites are S Cephei and T Lyrae, which get really red toward their minima (as long as they're still bright enough to show color, of course.)

#4 ronharper

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Posted 28 November 2012 - 05:00 PM

Todd,
Provided these are some hand picked "good ones", I really appreciate it. I have learned a few from you in onesies and twosies. For some reason, I just lack the gumption to seek them out on my own, but I respond well to the old folkways. A list like this is really helpful.
Ron

#5 Man in a Tub

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Posted 28 November 2012 - 07:08 PM

Provided these are some hand picked "good ones", I really appreciate it.


GULP! :scared:

They are not hand-picked. They are the carbon stars I have tracked down in an urban location with binoculars. Most of them are visibly red, or at least a reddish orange. However, as an example, RT Ori was not impressively ruddy to my eyes when I first observed it. Right now I see red. Patience is really necessary.

Exact coordinates are not in the file. The inclusion of alternate identifiers should help in many planetarium programs. For example, RT Ori is also identified as HIP 26032 which is the best choice for finding it in Stellarium because it will then be selected.

I have probably forgotten a few. For example, WZ Cas was forgotten.

Not included is RZ Peg* which I think I finally detected earlier this month with my Pentax 20x60 PCF WP II. But I need to look a few more times as soon as possible. I toss this one into the bloody ring as a challenge.

*Other identifiers: HD 209890, HIP 109089, BD +32 04335, TYC 02724-1872 1, J220552.9+333024

:grin:

#6 gwd

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Posted 29 November 2012 - 05:46 PM

U Camelopardalis.

After I saw this article:
http://www.spacetele...ages/potw1227a/

I had to try to find it in the binos. I got to hunt around for Kemble's Cascade and UV Cam and NGC 1502 in the same region. I go looking for one thing and that one thing leads to another....

#7 rookie

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Posted 29 November 2012 - 06:08 PM

Thanks for the nice list. There are some I have not found yet but you have included my favorite, U Hya.

Do you have a personal favorite, Todd?

#8 Man in a Tub

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Posted 29 November 2012 - 07:19 PM

Thank you, George. U Cam looks like a good one, but it is out of reach from my apartment window. I stopped sidewalk observing about two years ago. Fortunately, my west-facing window gives me a very worthwhile section of the night sky. Occasionally I go out into the floodlights. I've put U Cam on my list as unobserved. I've seen Kemble's Cascade/NGC1502 a few times. Very nice.

Hi, SV!

I think you mean V Hya. I certainly recall it as your favorite. It can be a hard one to see here. Timing for position in the sky as well as magnitude in its maximum/minima cycle is critical. It is certainly is a red one! I repeatedly tried re-observation earlier this year, but it eluded me.

A personal favorite is VX Andromedae. A binocular FOV includes a variety of stellar spectral types. Among the stars in my FOV, I'll mention nearby HIP 1474, a K2 star, and fainter HIP 1475, an M2 star. These stars by color contrast with VX And visually highlight the unique richness of carbon stars.

I made a correction in my OP. The list is arranged by constellation, not by RA. I hit a wrong button. Arranged by constellation is really better since I haven't included the RA/DEC coordinates.

#9 daniel_h

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Posted 30 November 2012 - 01:30 AM

Thanks Todd

#10 rookie

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Posted 30 November 2012 - 07:37 AM

Excellent recall Todd!
Last spring, I could not see V Hya with binos. It was too dim for my eyes and skies. I needed a telescope with more than 50 x and found it a dull brick red. OTOH U Hya was glorious golden orange, sharing the bino field of view with a triangle of yellow and white diamonds. I exercised my female perogative and changed my mind. :love:

#11 Man in a Tub

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Posted 30 November 2012 - 08:35 AM

Ask me my favorite carbon star six months from now! :grin:

I'm attaching a "fancier" PDF version of the Excel file in my OP. I added WZ Cas since I observed it a few years ago. Anyway, creating the PDF was an excuse to play around with MS Office 2010 (Excel) which just about everybody hates! This version includes the RA and DEC coordinates as well as alternate identifiers. It even has column headings. I did my best at proofreading.

P.S. I have also replaced the .xls file in my OP with better column spacing and landscape orientation.

Clear Skies,

Attached Files



#12 John_G

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Posted 01 December 2012 - 09:04 AM

Looking at my own SkyTools, I see about 8 or so in common with your list where I noted I could spot them with my 12x50s or 15x70s. I like to use my 90mm to hunt carbon stars but I always try with my binoculars as well. UX Dra and RY Dra are good targets. I had my first look at R Lep back in September. What's nice about carbon stars is if you've got a good chart you can often pinpoint even the higher magnitude stars just by their distinctive hue of red.

#13 John_G

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Posted 01 December 2012 - 02:18 PM

The first time I looked at T Lyr was with my 100mm and my Nagler 12mm. I knew I should have it my FOV but my eye kept searching and I couldn’t see it. Then I realized that it was already at the center of the EP but was such a deep, deep red that my eye kept somehow skipping over it without actually seeing it. I tried with my binoculars but no go.

#14 Man in a Tub

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Posted 01 December 2012 - 09:17 PM

Hi John,

I like SkyTools 3 Standard Edition. It is not just for planning. I can now easily organize handwritten observing notes with lists and notes. I didn't start looking for carbon stars right away. In mid-January 2008, my notes mention W Ori - probably my first carbon star. (Can almost five years be described as "several" years?)

I would like to get my carbon star observations up to 50. That would be respectable. I know about the Astronomical League's Carbon Star Observing Program - 100 carbon stars! But with binoculars? With reportedly 6891 carbon stars, maybe I can do it!

My November 3rd notes show that I saw T Lyr with my Fujinon 10x50 FMT-SX. I think my first T Lyr observation was last year - probably with my Pentax 20x60 PCF WP II. (Got to get those notes in order!)

Finding carbon stars is also good practice for other targets. Finding starfield patterns or "mini-asterisms" is crucial, and sometimes it takes a few star hops to get the exact field of view. That's the challenge I love!

When observing the more deeply red carbon stars, I often notice a slight delay until the carbon star is most visible. I assume this subjective, visual experience is tied to the Purkinje effect. V Hya, R Lep and T Lyr are most notable for this effect. I have never found a description, formulation or reference of this visual time delay. It seems that the visual lag occurs as we balance between the realms of the cones and rods.

I can observe some carbon stars with handheld binoculars (for example, UU Aur, W CMa and W Ori), but many require mounted observation with, if at all possible, the necessary binocular.

Here's a good list from the North Central Kansas Astronomical Society:

NCKAS Carbon Stars

I think this carbon star list from Christian Buil may be most helpful for binocular observers. I found it yesterday or the day before. The list is "adapted from Stephenson, 1989, catalogue of Cool Galactic Carbon Stars (2 Ed.) and contain[s] carbon stars brighter th[a]n Mv<8.5":

http://www.astrosurf...iar2/carbon.htm

Clear Skies,

#15 John_G

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Posted 02 December 2012 - 03:11 AM

Hi Todd

I use the standard edition myself. I've been working with the AL carbon star list for about 2 years now. I've got 37 now logged. This past summer, Y CVn was definitely my favorite. Visible and red even with the naked eye.






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