My Community

General Astronomy => Beginners Forum => Topic started by: migresinli on December 27, 2017, 03:04:04 PM

Title: Anything better than SkySafari 5 Pro?
Post by: migresinli on December 27, 2017, 03:04:04 PM
I was looking at the double star at Orion's head, Meissa, while looking at SkySafari 5 Pro and comparing the two. I saw a very faint star next to the double star that the app did not have. My first reaction was "I discovered a star!!!" but that thought left me about as quickly as it came. I looked at wikisky.org and found a photo of what I was looking at. It shows A LOT more stars than SkiSafari. I just wanted to see what the magnitude was. I am very surprised that it did not have it as I am in a very light polluted city. What should I look at to see what the star is? Is there a good OS X program?
Title: Re: Anything better than SkySafari 5 Pro?
Post by: neukascome on December 28, 2017, 09:33:21 PM
When you click on the 'Stars' Toolbar button, what is the limiting magnitude it displays?
Drag the slider right (i.e. make the magnitude limit increase) until the 'missing' star is seen.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: anstirabnas on December 29, 2017, 12:15:40 AM
I maxed out the stars still nothing....

If it helps, here is the star. I put the obvious red star where the missing one is

 bbcodeImage-js (do not remove or edit this tag)
(https://www.cloudynights.com/uploads/gallery/album_7050/sml_gallery_266948_7050_36467.jpg) (https://www.cloudynights.com/gallery/image/42198-unknown-star/)Here is a link to the wiki sky.org photo.
http://www.wikisky.o...img_source=DSS2 (http://www.wikisky.org/?ra=5.583867378211876&de=9.926033325829554&zoom=10&show_grid=1&show_constellation_lines=1&show_constellation_boundaries=1&show_const_names=0&show_galaxies=1&img_source=DSS2)
Title: Re: Anything better than SkySafari 5 Pro?
Post by: David Washington on December 30, 2017, 12:44:22 PM
I looked at SkySafari on both iOS and MacOS. There's nothing plotted there, as is the case with TheSkyX.

I don't know how large of a telescope you're using, but it seems unlikely that you'd see something not plotted at the magnitude limit of SkySafari from light polluted skies.

Could it be an internal reflection from your eyepiece?
Anything that comes to mind (like an geostationary satellite) would also be far to faint to see in a small telescope from light polluted skies.

Sorry I couldn't be of more help.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Eric Lara on December 30, 2017, 09:50:19 PM
ismosi,

I was thinking that it could be a reflection, but it was there in the same spot an hour later, and there when I used a 2x barlow. Could it still be a reflection?

Also I was using an 8" Dob with 12mm eyepiece.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: salonpeli on January 04, 2018, 03:54:06 PM
SkySafari Pro catalogs 27 million stars. Your 8" dob can detect stars down to about the 13th magnitude visually, that would be between 15 and 20 million stars. However long exposureimaging at 8" aperturemakes many times more stars detectable.

Gale
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Ralph Gleason on January 04, 2018, 04:09:25 PM
Quote
What is the focal length of the 8" Dob?

It's a Z8 so 1200mm. I could see it both at 100x and 200x (using a barlow).
Title: Re: Anything better than SkySafari 5 Pro?
Post by: circlemisde on January 08, 2018, 02:27:32 PM
Thanks for posting that Gary, but I'm fairly certain I had my fov correct as I was checking off the stars between the eyepiece and ss5. I even tried to double check this by putting both Meissa and Ori in the fov. I think I'll just have to look again in a few days and see if I can still find it. There must be something I'm doing wrong...
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Travis Kuhlman on January 10, 2018, 04:53:10 AM
Quote
I was looking at the double star at Orion's head, Meissa, while looking at SkySafari 5 Pro and comparing the two. I saw a very faint star next to the double star that the app did not have. My first reaction was "I discovered a star!!!" but that thought left me about as quickly as it came. I looked at wikisky.org and found a photo of what I was looking at. It shows A LOT more stars than SkiSafari. I just wanted to see what the magnitude was. I am very surprised that it did not have it as I am in a very light polluted city. What should I look at to see what the star is? Is there a good OS X program?

Asteroid?
Title: Re: Anything better than SkySafari 5 Pro?
Post by: neaubigvapec on January 12, 2018, 07:51:40 AM
A program is only as good as the catalog it relies on, and no star catalog is perfect. Having said that, SkySafari uses the Hubble Guide Star catalog, which is worse than most large catalogs. Filtering something newer by magnitude would yield better results.

Places where star catalogs are most likely to be deficient (either missing stars or showing ones that aren't there) include very close to bright stars and inside bright nebulosity. It's also very hard to filter out intense starlike deep-sky objects such as galaxy cores.

The rule of thumb is to never trust any star catalog completely. When in doubt, go instead to photographic plates such as the ones available in Wikisky.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Demetrius Bryan on January 13, 2018, 03:14:22 PM
Hi:

Maybe Bill Tschumy will see this thread and address some of the questions raised. Myself, if it ever clears up, I will see if I can see a star there.

Sky Tools 3 is very good with multiple star systems. I see that Meissa is 5 star system. The AE system looks like this:

AE: 3.39+9.22 mag, PA 279° Sep 151.10" (1991)

At magnitude 9 and a separation of 151" seconds, that looks like a possible candidate.

The AB System looks like this:

AB: 3.39+5.45 mag, PA 44° Sep 4.30" (2003)

The sep refers to the separation between the two in arc-seconds, at 4.4", the B star is relatively close. At 151", the E star is quite far away.

PA refers Position Angle, the orientation between the A star and the second star. The B star is northeast, the A E star is almost due west. That seems about right without doing a drawing myself.

At magnitude 9, the E star should be quite bright in an 8 inch and at 151 arc-seconds separation, that's about 34 times the B star.

I suspect that what bdwg saw is the E star of Meissa.

And bdwg should be commended for his careful observation..

Jon
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Jeff Smith on January 15, 2018, 10:05:27 AM
Jon asked me to chime in on this. It could very well be the E star in the multiple star system. I've asked him to post a screen shot from SkyTools of the area.

I'm not sure a better catalog in SkySafari would solve the problem. I looked at the same area in Starry Night Pro Plus. This app uses the USNO catalog and there was nothing in the marked area. There were stars plotted down to 18th mag in other areas of the field, but nothing where bdwg indicated he saw the missing star.

I have nothing but admiration for SkyTools. Greg has gone to great lengths to add all the component stars in the Washington Double Star catalog to his database. It doesn't surprise me that he plots stars that won't be found in any of the standard star catalogs, no matter how deep they go. I would love to do something like that in SkySafari, but I'm not sure when I would get the time.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Steven Morrison on January 20, 2018, 04:16:23 PM
Here's a cropped and rearranged SkyTools 3 screen shot of the Meissa region. In the lower left you will see the information on the star, in the lower right you will see the separation and angle between the two selected objects. The AB double is visible at the top of the screen.

JonAttached Thumbnails
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Alex Loftus on January 20, 2018, 11:18:54 PM
Quote
:waytgo:

SkyTools 3 is a powerful program and as Bill said, Greg Crinklaw has done a wonderful job with it. It's basically a planning program, a searchable database. And like Bill, Greg is an avid observer. If you google an object and include Skyhound, you will likely find information on observing that object.

It Skytools better than SkySafari:

Skytools runs a PC and is not so well suited for observing in the field. I use Skytools for situations like this one. Skysafari 5 Pro is an extremely powerful program and does a better job with multiple stars that any mobile app I know of and better than every desktop program I know of except Skytools..

http://www.skyhound.com/skytools.html (http://www.skyhound.com/skytools.html)

Jon
Title: Re: Anything better than SkySafari 5 Pro?
Post by: olchakisur on January 23, 2018, 02:42:09 AM
Jon!!!!

That's the one! Thank you very much for taking the time to verify that I am not crazy. When you are new at this, it's easy to think you are doing something wrong. It sounds like you and others hold Skytools in a high regard. Are there any other programs that are similar in quality that would show Meissa E? Do you even call it "Meissa E?"

Most of all, thank you for letting me know that it was a magnitude 9. That was about the faintest star I could see. I am happy to know its magnitude, so now I can set SkySafari to max the stars out at 9 when I am in my back yard.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: renjaysunsdis on January 23, 2018, 08:07:23 AM
I was at that star the other night and saw the same thing. I use Sky Safari 4 plus and was unable to locate the companion star either. Sometimes that just happens. I assumed it was the star mentioned as being 4.3" away. (C8, 17mm, ~118x)
Title: Re: Anything better than SkySafari 5 Pro?
Post by: holdfontrosci on January 23, 2018, 02:53:06 PM
Quote
Jon!!!!

That's the one! Thank you very much for taking the time to verify that I am not crazy. When you are new at this, it's easy to think you are doing something wrong. It sounds like you and others hold Skytools in a high regard. Are there any other programs that are similar in quality that would show Meissa E? Do you even call it "Meissa E?"

Most of all, thank you for letting me know that it was a magnitude 9. That was about the faintest star I could see. I am happy to know its magnitude, so now I can set SkySafari to max the stars out at 9 when I am in my back yard.


bdwg:

Honestly, I cannot verify that you are not crazy.. Anyone who would spend good money on a telescope so they could go out in the cold and look at stars when they should be in a warm bed sleeping is, at best, borderline crazy.

But, crazy or not, I can verify that you are a careful observer with an eye for detail.

I don't know if there are other programs that would identify Meissa E. Some double stars have short periods and to provide accurate separation and position angle data, they need to calculate the orbit. Sky Safari does this, Sky Tools does this, I am not sure about other programs..

Jon
Title: Re: Anything better than SkySafari 5 Pro?
Post by: otdaebreathat on January 23, 2018, 06:19:32 PM
Thanks Gary!

I downloaded and installed SkyTools and have been playing with it all day. It's a very cool program, but I do not think it replaces SkySafari at all. As mentioned before, it is PC based (no Mac or app option) and it is really more of a planning tool. Yet it is important to point out that it is capable of having a lot more stars, and I do mean a lot more.

Now that I have SkyTools, I don't think I could give it up, but there is no way it will stop me from using SkySafari in the field.

Thanks again to everyone for their help and time!
Title: Re: Anything better than SkySafari 5 Pro?
Post by: John Daniels on January 25, 2018, 01:18:41 PM
Quote
Thanks Gary!

I downloaded and installed SkyTools and have been playing with it all day. It's a very cool program, but I do not think it replaces SkySafari at all. As mentioned before, it is PC based (no Mac or app option) and it is really more of a planning tool. Yet it is important to point out that it is capable of having a lot more stars, and I do mean a lot more.

Now that I have SkyTools, I don't think I could give it up, but there is no way it will stop me from using SkySafari in the field.

Thanks again to everyone for their help and time!


I use SkySafari 5 Pro in the field and for most uses. Skytools 3 serves as a resource, mostly for double stars.

Jon
Title: Re: Anything better than SkySafari 5 Pro?
Post by: Demetrius Bryan on January 30, 2018, 05:32:37 AM
Without knowing the orientation and field of view in Jon's image, it is hard to say if the "E" star is what you saw. It doesn't look like it is in the same position or distance from the AB pair to me. I'm not convinced the mystery is solved.
Title: Re: Anything better than SkySafari 5 Pro?
Post by: ricoperte on January 30, 2018, 05:43:50 AM
The star in question is actually the AC pair, (C component with mag 11.2) the star that is closest to the AB pair. I downloaded skytools, and I assumed the E star would be the faintest star, not the star furthest away. So not the E star, but the C star was the one missing from SkySafari.