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Asbytec
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Reged: 08/08/07

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HIP 17129 Perseus
      #5529275 - 11/20/12 01:25 AM Attachment (58 downloads)

Well, what a nice little double. I guess at spectral type F5, they should be more yellow. I saw them with a hint of soft orange. They appeared very close in magnitude and color.

Estimating the Sep was a bit of a challenge, the first ring was rather dim. But, one might almost see a complete ring around each, maybe with a bit of overlap. So, I estimate that puts the companion in the second dark space, thereabout, maybe near the third maximum (second ring.)

It was definitely double at 110x, but much easier split at 160x. I observed at 260x (150mm MCT f/13, UO 12mm HD Ortho and Celestron 2x shorty working at 1.6x)

Edited by Asbytec (11/20/12 01:41 AM)


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VanJan
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Reged: 07/09/08

Re: HIP 17129 Perseus new [Re: Asbytec]
      #5529564 - 11/20/12 08:14 AM

Nice drawing! Latest data from WDS is 1.9", 60d, 2012. This pair was already on my to-do list, and now I'm really going to make a concerted effort to observe this pair next steady night. Wonder if I have any chance of a clean split with my 90mm refractor, or will this one turn out to be a "kissing" pair with that aperture

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Asbytec
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Reged: 08/08/07

Loc: La Union, PI
Re: HIP 17129 Perseus new [Re: VanJan]
      #5529579 - 11/20/12 08:25 AM

Should be doable with a split. When you get a chance, take a peak.

Thanks for the data, I should have looked it up. I missed the sep call by a good bit. Life sucks!


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Astrodj
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Reged: 08/24/11

Loc: Missouri
Re: HIP 17129 Perseus new [Re: Asbytec]
      #5532868 - 11/21/12 07:46 PM

Norme,

I'll be checking this one out later when it clears the trees. Thanks for the heads up.


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Asbytec
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Re: HIP 17129 Perseus new [Re: Astrodj]
      #5533024 - 11/21/12 10:07 PM

I hope you enjoy it, DJ.

I am trying to observe more double stars, but I need a better method. I failed on HIP 114 last night, took a long time to find it in the moonlit sky. Even then, it did not resolve.


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Astrodj
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Reged: 08/24/11

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Re: HIP 17129 Perseus new [Re: Asbytec]
      #5533278 - 11/22/12 01:47 AM

Seeing was 5/10 tonight here. Still, not a difficult split in the 10" f4.7 dob. Tight, but clean.

I observed it at 181x and 300x. At 181x (Cave 6.6mm Ortho) I had a very good split. I could see a slight difference in color. This was more evident at the higher power though.

At 300x (N.S. 4mm Ortho) one star appeared yellow with orange tints, and the other more golden yellow.

I started from Zeta Per, a very pretty multiple star. From there I hopped to STF 431, an unequal double of mags 5 and 10 about a half degree east of the target. STF 431 has a few field stars nearby that make it attractive.

My first time for STF 431 and 425.

While I was in the area I took a shot at STT 531 an Otto Struve double. It is located just north of the California Nebula, about 5 deg NE of STF 425. At mags 7 and 9, 1.5" of arc, it's a bit of a challenge. The magnitude 9 secondary seemed dimmer to me. I would have estimated 10 or 10.5. At 300x the primary appeared yellow and the dimmer secondary almost had no discernible color, maybe dim white.


Does HIP 114 have a STF#? My software uses ADS and TYC designations.


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Asbytec
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Reged: 08/08/07

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Re: HIP 17129 Perseus new [Re: Astrodj]
      #5533306 - 11/22/12 02:24 AM

Sounds like the night I wish I had. I am envious, and really just in need of a good plan and method. I might repeat your observations...sounds like fun. I could not notice any difference in color, despite trying like the dickens. Well done.

Yes, it does. Its ADS 252, I think. In fact, I had to use sinbad to look up the HIP number. Let me see if I can confirm the ADS number.

Edit: Actually, this is part of the method problem: cross referencing catalogs. I stumbled over this nice looking double on the web, I think ADS 252. It gave no other designation, but it gave RA and Dec. So, I looked on the charts for a star that matched that description as close to that position as possible. I might have picked it off incorrectly. I found the star I was looking for, but maybe it was not the double.

Still looking for that original reference.

Edited by Asbytec (11/22/12 02:38 AM)


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VanJan
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Reged: 07/09/08

Re: HIP 17129 Perseus new [Re: Asbytec]
      #5533396 - 11/22/12 05:58 AM

HIP 114 is ADS 17167, or, in the WDS, HO 208 at 00h 01.5m +30d 44': 8.20, 9.81: 1.2", 188d, 2009: G0IV

ADS 252 is STF 24 at 00h 18.5m +26d 08': 7.79, 8.44: 5.2", 247d, 2007: A2

Woo Hoo! I was able to get a clean split of STF 425 with my 90mm at 180X. Both orange-white with a 9th magnitude companion sp.

While in the area, I visited the nearby and similar in magnitudes but closer Burnham 533: 03h 35.6m +31d 41': 1.1", 222d, 2012: F4V. Best I could do with my 90mm at 230X was a pale orange figure-eight detection of duplicity, with a white 9th magnitude companion np (C component in WDS) and a closer 11th magnitude companion sp.

With your 150mm, though, I'm thinking this pair will be a nice, tight, clean split for you. Steady Skies!

VanJan


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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
Re: HIP 17129 Perseus new [Re: VanJan]
      #5533401 - 11/22/12 06:05 AM

VanJan, thank you. I was just coming back to correct my post. Another problem with my double star method is memory.

Yea, I really wanted to observe ADS 252, remembered the right designation - wrong star. Congratulations on your success.

The sun has set...wish me luck.


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Astrodj
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Reged: 08/24/11

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Re: HIP 17129 Perseus new [Re: Asbytec]
      #5533699 - 11/22/12 10:34 AM

Thanks VanJan, for the info.

Norme, I spend more time cross referencing than I would like. I should use Simbad and WDS more than I do. Hope you had a good night!


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Asbytec
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Reged: 08/08/07

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Re: HIP 17129 Perseus new [Re: Astrodj]
      #5533841 - 11/22/12 12:08 PM

So true, DJ. Had a great night, but left the double list pretty much untouched.

Absorbed with Jupiter. Got Eta Perseus, though.


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fred1871
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Reged: 03/22/09

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Re: HIP 17129 Perseus new [Re: Asbytec]
      #5537696 - 11/24/12 07:02 PM

One of the things that shows in this thread is the problem of cross-referencing double star names. Because doubles often have multiple designations - maybe a Struve number, plus SAO, plus ADS, plus HIP etc etc it can get pretty time-consuming in identifying which pair is being talked about.

Common practice is to use discoverer designations - hence STF (Struve, WGF), BU (Burnham), HJ (John Herschel), etc.

Unfortunately, some software programs decide to use ADS numbers which generally are now applied only to Aitken's discoveries - his big catalog isn't anywhere near complete enough to be a standard reference, and it also doesn't cover much of the southern sky.

SAO should become obsolete. It's not really a useful catalog anymore for the ordinary observer. HIP is fine as a general star reference, but it's not designed for double star referencing, so best kept, like Aitken, for doubles "discovered by...". Ditto TYC.

One can always, with brighter pairs, refer to stars by Greek letter/Flamsteed number within a constellation; that's usually easy to check via an atlas. Referring by proper name is more obscure - some of these are used for more than one star, spellings vary, and many of them are obscure. Wikipedia, last time I looked, listed 400 or so - it adds one more step in identifying, unless it's Sirius or Rigel or Antares....

So, I'd suggest in future it'd be simpler if a thread like this was titled "STF 425 in Perseus" rather than HIP 17129 in Perseus. Discoverer reference. A better fit for double star observers.

Edited by fred1871 (11/24/12 07:20 PM)


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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
Re: HIP 17129 Perseus new [Re: fred1871]
      #5537726 - 11/24/12 07:29 PM

Thank you for making that clear, I am pretty new to doubles. Sounds like great advice I will do my best to adhere to.

I used HIP because my main source (Stellarium) uses it. I do have to search for STF and other designations and hope SINBAD reference pops up. Then grab the HIP number to find it in Stellarium so I can star hop to it. It's kind of tough, and I do need a better method. Thank you.


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fred1871
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Reged: 03/22/09

Loc: Australia
Re: HIP 17129 Perseus new [Re: Asbytec]
      #5537839 - 11/24/12 08:57 PM

I use the Washington Double Star Catalog (WDS) as my primary reference. Trouble is, it's too darn BIG. So I have cut-down versions of it, which I did myself, manually - the Saguaro group did a similar thing with more IT input, various versions over the years, but I was never happy with their editing. Too many doubles that you can see with a 6-inch scope dropped off their list - and I don't just mean faint ones. Plenty edited out that were brighter than mag 9, often because they were uneven and fairly close.

At the moment I don't have a one-site-solves-the-problem suggestion. There are several on-line access points for versions of WDS or the Saguaro/SAC (not bad, if you recognise the need to supplement it, sometimes in a big way) etc. And there's the "Double Stars Database" (another access point for the WDS) being discussed in another thread in this forum.

The Haas book on double stars for small telescopes is useful but of course has a limit on the number of objects per constellation.

So, a few thoughts on the 'access' issue for doubles. Currently, I've not seen any software packages that offer a simple access via standard ways of naming doubles - the packages appear to be designed by folk who aren't very familiar with double stars. Hence the SAO and ADS and similar usages.

Perhaps someone out there can make a new attempt, similar to SAC, but do a better editing job.


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Asbytec
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Reged: 08/08/07

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Re: HIP 17129 Perseus new [Re: fred1871]
      #5537918 - 11/24/12 10:04 PM

You know, for a beginner, maybe the Eagle Creek list is a good place to get your feet wet, then advance to different catalogs and challenges. Yes, there are more than enough doubles to keep one busy for several life times.

I like tight doubles, good seeing here. But, color is nice, too. One project I thought to start was a tight (for a 6") colored double list. Maybe compile some candidates, then go out and observe them. If they are "showcase" color and say 2" or less, compile it.


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