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#301 7331Peg

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Posted 20 August 2014 - 11:03 PM

Bill, I have a question on Sky Safari 4 for the IPAD.  Tried to find a place on the support page to ask this, but didn't have any luck.

 

I did a search for a double star, STF 2229, looking to see if a distance for it was shown.  Stelladoppie, which I use for distances when they're listed doesn't show anything, and neither does Simbad (no parallax), which I use also.   Sky Safari returned two entries for STF 2229, one showing a distance of 120pc (400 LY), and the other showing 15.4 pc (50.3 LY).   There's also a discrepancy between the two entries on magnitudes for the primary and secondary.  The first entry mentioned shows magnitudes of 8.14 and 10.30, while the second shows magnitudes of 9.65 and 10.30.

 

My main question is where does Sky Safari 4 pull that information from, and second,why are there two entries listed?

 

 

John :refractor:



#302 Jon Isaacs

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Posted 21 August 2014 - 09:31 PM

Bill, I have a question on Sky Safari 4 for the IPAD.  Tried to find a place on the support page to ask this, but didn't have any luck.

 

I did a search for a double star, STF 2229, looking to see if a distance for it was shown.  Stelladoppie, which I use for distances when they're listed doesn't show anything, and neither does Simbad (no parallax), which I use also.   Sky Safari returned two entries for STF 2229, one showing a distance of 120pc (400 LY), and the other showing 15.4 pc (50.3 LY).   There's also a discrepancy between the two entries on magnitudes for the primary and secondary.  The first entry mentioned shows magnitudes of 8.14 and 10.30, while the second shows magnitudes of 9.65 and 10.30.

 

My main question is where does Sky Safari 4 pull that information from, and second,why are there two entries listed?

 

 

John :refractor:

 

 

I believe Sky Safari uses the WDS.  For what it's worth, Sky Tools 3 which also uses the WDS lists two stars, STF 2229 A and ST 2229 B which have different properties.. 

 

Jon



#303 7331Peg

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Posted 21 August 2014 - 11:07 PM

The WDS doesn't list distances, so that information is coming from somewhere else.  And the A and B components are listed in both entries returned from the search, so that doesn't answer the question, either.

 

Still waiting to hear from Bill or Tim on this.

 

John



#304 btschumy

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Posted 22 August 2014 - 09:47 AM

John,

 

Tim builds the catalog we use so we may have to wait to hear from him for a definitive answer.  He is away for the next 10 days

 

First, let me say that SkySafari pulls data from many catalogs, matching up objects from one catalog to those of others.  It is a difficult task but it results in one unified, cross referenced database.

 

Jon is right that the two entries correspond to the two components of the double.  The distance discrepancy is (I believe) due to the fact that this is an optical double and the two components are actually at different distances.  I unfortunately have been unable to verify this because I don't have all the raw databases Tim uses on my computer.

 

It is also the case that the primary shows a slightly different magnitude in the two entries (8.14 vs 9.65).  This may just have to do with how certain components were matched to other catalogs.  The magnitudes of particular stars in different catalogs can vary by quite a bit.  This may be due to intrinsic variability of the star or it may be because a slightly different photometric system was used in the two cases.

 

Many people intuitively think that astronomical data is precise.  However, when you delve into it the catalogs are filled with errors and inconsistencies.  It is a huge task to try to sort all this out to construct a unified database like SkySafari uses.  We get occasional queries saying our data has an error because some star in our database shows a slightly different magnitude that the database they are looking at.  It is generally not an error but just that the values really do differ depending  upon what source you use.



#305 Jon Isaacs

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Posted 22 August 2014 - 11:42 AM

Bill:

 

Indeed.. Errors and inconsistencies, I thought I had found an error in Sky Safari when it listed 10 Ursae Majoris as being a member Lynx but I looked it up and sure enough, 10 UM is in Lynx.. how weird is that?

 

The plot thickens.. Checking on 10 Ursae Majoris in SSP 4.. It lists it as being in Gemini... now I am confused.

 

Jon



#306 btschumy

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Posted 22 August 2014 - 12:19 PM

Jon,

 

Are you sure you are not in orbit mode?  10 Uma is showing as currently in Lynx for me.  It could be in a different constellation if you are in orbit mode or if you have run time forward to such a degree that proper motion has carried it into another constellation boundary.



#307 7331Peg

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Posted 22 August 2014 - 01:09 PM

Thanks for the reply, Bill.  

 

I'm aware of the inconsistencies between the various stellar databases as I run into them all the time.  The distances listed for the two components of STF 2229 really intrigue me, though, since the usual sources I look at don't list anything at all on them.   If Tim could provide that information, it would definitely come in handy.

 

John



#308 Jon Isaacs

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Posted 22 August 2014 - 09:17 PM

Jon,

 

Are you sure you are not in orbit mode?  10 Uma is showing as currently in Lynx for me.  It could be in a different constellation if you are in orbit mode or if you have run time forward to such a degree that proper motion has carried it into another constellation boundary.

 

Bill:

 

I believe you're right, I do remember that somehow I did end up in the orbit mode.

 

Jon



#309 stevesreed

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Posted 02 September 2014 - 11:51 AM

 

 

We will be putting full support for SkyQ Link into SkySafari in the next couple of months.

Bill

 

Any update on SkyQ support?

 

The code is written and in testing now.  This has been a joint effort between us and Celestron.  It will be rolled out in an update to their SkyPortal app first and then we will integrate it in SkySafari.  The integration should not take too much work, but we have some other things on our plate as well.  It might be available in early October or possibly sooner.

 

Will that update also add support for the Evolution Mounts? I assume their wifi implementation is pretty similar to SkyQ.



#310 btschumy

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Posted 02 September 2014 - 02:04 PM

Yes, the Evolution mounts are controlled identically to SkyQ Link.



#311 stevesreed

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Posted 02 September 2014 - 04:47 PM

Yes, the Evolution mounts are controlled identically to SkyQ Link.

Thanks. That's good to know.
 

I'll go ahead and order Sky Safari Pro now, so I get the update as soon as it's available :)



#312 YankeeJeff

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Posted 05 September 2014 - 07:21 PM

I'm trying to add Collinder 26 to an observing list for Cassiopeia but I can't find it. When I seach for "Collinder" (without the #) I see that some Collinder listings are skipped. Am I doing something wrong in the search?? - I don't see any listings for Melotte so I can't find it as Mel 15 either. Its a required object for the Astronomical League Deep-Sky Binocular club. Am I missing something in the install?

 

Thanks



#313 YankeeJeff

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Posted 05 September 2014 - 07:22 PM

I'm trying to add Collinder 26 to an observing list for Cassiopeia but I can't find it. When I seach for "Collinder" (without the #) I see that some Collinder listings are skipped. Am I doing something wrong in the search?? - I don't see any listings for Melotte so I can't find it as Mel 15 either. Its a required object for the Astronomical League Deep-Sky Binocular club. Am I missing something in the install?

 

Thanks



#314 beatlejuice

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Posted 05 September 2014 - 07:47 PM

You want IC1805 within which is mel 15 or collinder 26

 

Eric



#315 btschumy

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Posted 05 September 2014 - 08:20 PM

SkySafari does not have every Collinder or Melotte cluster.  We pull our data from a couple of meticulously compiled modern catalogs.  You can read more about where our data comes from here:

 

http://www.skysafari...es/deepsky.html

 

This is the description of where our open clusters comes from:

 

Revised New General Catalog and Index Catalog - Wolfgang Steinicke's revised list of NGC and IC objects. The best effort resulting from the NGC-IC project, an attempt to correctly re-measure and re-identify all of the original NGC and IC objects using modern data like the Digitzed Sky Survey.

 

Open Clusters and Galactic Structure - Wilton S. Dias (UNIFEI); Jacques Lépine (IAG-USP); Bruno S. Alessi and André Moitinho (UL). The most comprehensive, modern, currently-mainted catalog of optically visible open clusters currently available.

 

Catalog of Open Cluster Data, 5th Edition - by G. Lynga, at NASA's Astronomical Data Center. The fifth edition of the Lund Catalogue of Open Cluster Data gives key information for all known open star clusters in this galaxy. An older reference (1987), but still useful.

 

It appears that Col 26 and Mel 15 are not really separate clusters from IC 1805 (according to Archinal and Hynes).  I don't disagree that it might be useful to list them as sub-condensations within IC 1805, but that is not how they are listed in the modern catalogs we use.



#316 YankeeJeff

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Posted 05 September 2014 - 10:28 PM

Thank you both - Collinder 26 was there under IC 1805, also found Collinder 36 as Trumpler 3.



#317 StarCurious

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Posted 08 September 2014 - 03:31 PM

 


 


We will be putting full support for SkyQ Link into SkySafari in the next couple of months.

Bill
 
Any update on SkyQ support?
 

 

The code is written and in testing now.  This has been a joint effort between us and Celestron.  It will be rolled out in an update to their SkyPortal app first and then we will integrate it in SkySafari.  The integration should not take too much work, but we have some other things on our plate as well.  It might be available in early October or possibly sooner.

 

 

Bill,

I have SF4+ in iPadMini and SF4 Pro on Android. The SkyQ Link would plug into the accessory port of my Celestron NexStar 102 SLT and I can even disconnect the Hand Controller (no more cord wrap), hopefully supported by the next release of SF4+ for iPad.

Will the next release of SF4 Pro for Android can be used to connect to the SkyQ Link?

Thanks,
Joseph



#318 btschumy

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Posted 08 September 2014 - 05:25 PM

The next release of SkySafari for iOS should support the Celestron WiFi module.  We are going to be submitting a release soon for iOS 8 compatibility.  

 

I can't promise the *next* Android release will have it, but it should only be a month away or so.








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