At face value, I cannot say from that photo. What is the field of view and the telescope, camera, exposure details, etc? This additional information should provide the image scale and insight into your photo which will greatly help others analyse the photo.
Looking at your image and based on my interpretation of orientation and distance, I don’t think that the smaller star near Sirius is a good candidate for being Sirius B, and here is my reasoning:
When comparing your star field to SkyTools, the smaller companion star in your image seems to be located about North of Sirius A, whereas I understand Sirius B to be East of Sirius A.
Looking at the overall image scale, the distance between GSC 05949-2774 and Sirius is 5’ 27”, which is 327 arcsecs. Using this as a yardstick, I estimate that the distance between Sirius A (centroid) and your candidate star to be around 50 or 60 arcsecs? The published value is just over 8 arcsecs for the year 2008.
I could be wrong, and it would be nice if that were the case! I wonder if anyone else can shed any further light on this, or verify that I have N & E correctly oriented.
G'day Dennis,
You are correct. It is not Sirius B.
I've learnt something. Thanks.
Regards
Vincent
Quote:
Originally Posted by Dennis
Hi Vince
Looking at your image and based on my interpretation of orientation and distance, I don’t think that the smaller star near Sirius is a good candidate for being Sirius B, and here is my reasoning:
When comparing your star field to SkyTools, the smaller companion star in your image seems to be located about North of Sirius A, whereas I understand Sirius B to be East of Sirius A.
Looking at the overall image scale, the distance between GSC 05949-2774 and Sirius is 5’ 27”, which is 327 arcsecs. Using this as a yardstick, I estimate that the distance between Sirius A (centroid) and your candidate star to be around 50 or 60 arcsecs? The published value is just over 8 arcsecs for the year 2008.
I could be wrong, and it would be nice if that were the case! I wonder if anyone else can shed any further light on this, or verify that I have N & E correctly oriented.
No worries. What software or star maps did you use to establish the identity of GSC 05949-2774? I have found quite a variance in magnitude of these fainter stars depending on which catalogue the reference data comes from, such as GSC, UCAC, UNSO, etc.
I also find it quite confusing determining which is E and W in the eyepiece, depending on whether I am using a diagonal or not, or a refractor (single objective) or reflector (2 mirrors). In the end, I just turn off the mount’s motor and see which way the star drifts.
I have been looking far and wide for other images of Sirius the surrounding star field. I was so thrilled to have Googled yours and the fantastic discussion, that I have just registered.
I am an amateur astronomer in Wilmington, North Carolina, USA. I have jumped back in to this hobby in hopes of learning more about nearby stars. I started with my 40 year old 6 inch reflector and added a modified Logitech webcam. I imaged the brightest star, Sirius, just to learn technique, and rapidly found myself having the same problem: which way is North? I too thought I might image Sirius' Pup. No luck on the Pup (my equipment isn't capable), but I have run into an interesting problem of identifying the stars within 3-10 arcminutes of Sirius. I got into that to match cataloged stars to my pictures in order to find North. That worked, but I have not been able to identify all of the stars in the catalogs so far. I'm just learning the catalogs. I found all except 3 on Simbad.
Here is one of my pictures of Sirius (taken 20 Jan 2008). The field is approximately 7x10 arcminutes. I rotated it to match your picture (which a is much wider field than mine)
Using a match to published stars (and later the method of switching off the drive), I determined that North is about 10 degrees left of the top diffraction spike and East is toward the right. This would put Vince' star about NE.
I don't see the bright star to the NE in my images(Sirius' glare may overwhelm it in my old telescope). But I am so happy to see that you confirm the other stars in the field. I wonder if you or other members of this forum might have similar pictures of the star field near Sirius?
Thanks so much for the opportunity to participate in your forum.
Welcome to Ice In Space and it is great news to hear of you jumping back into astronomy. I suspect the hobby may have changed a little, depending on when you temporarily parted ways?
You've got that right, however many things are the same. I was an enthusiastic Amateur as a teen, thought I was going into physics professionally. I then diverted into other careers and interests, but kept my 60's vintage Criterion RV-6, getting it out occassionally. (I've dated myself there!) Recently, with access to so much in the way of astronomy advances on the Internet, I felt the urge to get back into it. I have spent about a year and a half in our local astronomy club learning as much as I can. I just purchased a gently used Celestron c11, matched it to a Losmandy G11 mount. I feel like I'm beginning to find out what is possible in modern amateur astronomy.
I have become very interested in Nearby stars - hence the time I've spent on Sirius and other nearby bright stars. But I've also enjoyed other objects and double stars.
Thad, Nice to hear you've got back into Astronomy after a long rest.
You'll have to tell some of your fellow Cape Fear members to come on down and join in the fun on IIS.
Good luck with your exploits on trying to find the pup.
G'day Thad,
Sorry for my delay.
I uploaded a full image of Sirius taken with a 6 megapixel QHY8 camera.
The field of view is about 170x111 arc mins. A 1 sec exposure.
I hope you can adjust your seeing of this image, it's only a 50% jpeg.
North is up and east is to the left in this image.
If you point your scope south to a star then drive or push the tube down, you will then see the stars move to the northside of your eyepiece.
Again, if you drive or push the tube west, you will see the stars move to the east side of your eyepiece. More mirrors, more changes
You may be able to image the pup with your equipment if you can increase the magnification and stack a lot of the images. There are a few good programs freely availabe for that purpose.
Welcome to our group.
Vincent
Quote:
Originally Posted by Thad C.
Hello Vince and Dennis,
I have been looking far and wide for other images of Sirius the surrounding star field. I was so thrilled to have Googled yours and the fantastic discussion, that I have just registered.
I am an amateur astronomer in Wilmington, North Carolina, USA. I have jumped back in to this hobby in hopes of learning more about nearby stars. I started with my 40 year old 6 inch reflector and added a modified Logitech webcam. I imaged the brightest star, Sirius, just to learn technique, and rapidly found myself having the same problem: which way is North? I too thought I might image Sirius' Pup. No luck on the Pup (my equipment isn't capable), but I have run into an interesting problem of identifying the stars within 3-10 arcminutes of Sirius. I got into that to match cataloged stars to my pictures in order to find North. That worked, but I have not been able to identify all of the stars in the catalogs so far. I'm just learning the catalogs. I found all except 3 on Simbad.
Here is one of my pictures of Sirius (taken 20 Jan 2008). The field is approximately 7x10 arcminutes. I rotated it to match your picture (which a is much wider field than mine)
Using a match to published stars (and later the method of switching off the drive), I determined that North is about 10 degrees left of the top diffraction spike and East is toward the right. This would put Vince' star about NE.
I don't see the bright star to the NE in my images(Sirius' glare may overwhelm it in my old telescope). But I am so happy to see that you confirm the other stars in the field. I wonder if you or other members of this forum might have similar pictures of the star field near Sirius?
Thanks so much for the opportunity to participate in your forum.
G'day Dennis,
The program I use is TheSky6 Pro. It uses the Tycho and UCAC2 plus several others. It's a very good program and not cheap. I use it for astrometry.
Give the tube a little nudge. You should see which way the stars move.
The direction change with odd and even number of mirrors etc.
Regards
Vince
Quote:
Originally Posted by Dennis
Hi Vince
No worries. What software or star maps did you use to establish the identity of GSC 05949-2774? I have found quite a variance in magnitude of these fainter stars depending on which catalogue the reference data comes from, such as GSC, UCAC, UNSO, etc.
I also find it quite confusing determining which is E and W in the eyepiece, depending on whether I am using a diagonal or not, or a refractor (single objective) or reflector (2 mirrors). In the end, I just turn off the mount’s motor and see which way the star drifts.
Thanks Vincent and xstream , again I appreciate the very warm welcome.
Thanks Vince for your info on your Sirius picture. For some reason I can't see attachments now. I'm trying to figure out if they were somehow blocked by my browser or firewall settings. I clearly could see your previous pictures.
I'll work on it, perhaps there's something I haven't figured out about this site (although I've been using the Internet for 12 or 13 years and computers for more than 30, this is my first forum). Thanks for your advice on the Pup. I'm tooling up for the next clear sky night! With the weather of Coastal NC and my work schedule, I get just a few opportunities per month.
Thank you xstream for extending the invitation to my fellow Cape Fear Astronomical Society members. I will definately convey your good will.
I've been a member of CFAS for about a year and a half. The Society just celebrated it's 25th anniversary. Our sister society is in Australia: the Astronomical Society of Albury Wodonga. My undersatanding is that at least one of our members visited ASAW about 10 years ago.
Thanks Vincent and xstream , again I appreciate the very warm welcome.
Thank you xstream for extending the invitation to my fellow Cape Fear Astronomical Society members. I will definately convey your good will.
I've been a member of CFAS for about a year and a half. The Society just celebrated it's 25th anniversary. Our sister society is in Australia: the Astronomical Society of Albury Wodonga. My undersatanding is that at least one of our members visited ASAW about 10 years ago.
You're welcome Thad.
There are a few ASAW members who are a part of this forum, I being among one of them.
Sorry to go off thread subject - We have lost contact with the executive and are very keen to reestablish communication. Can you please pass on my details. I have PMed you also.
Cheers
Petra de Ruyter
Secretary - Astronomical Society of Albury - Wodonga
Secretary - Border Stargaze 2008 Committee
The Cape Fear Astronomical Society has a new Secretary and possibly a new newsletter editor. I have already extended your Society's greetings through our list-server email. I will contact the new Secretary specifically and also bring this up at our monthly meeting next week.
Thank you for your interest in maintaining contact.
As I have mentioned, I'm new to the forum format. I'm trying to figure out how to respond to your IM.
Thad, Nice to hear you've got back into Astronomy after a long rest. 
