Theta Scorpii (Sargas)

[EpickCrom]

G'day fellow observers!

This one has me scratching my head. I was out just now observing in Scorpius with my 10 inch dob. Sky Safari shows that Sargas (Theta Scorpii) is a double star with components mag1.8 and 5.3 with a seperation of 6.5"

This should be cannon fodder for my 10 inch but try as I may I could not split it! No companion star anywhere to be seen. I easily split Antares at 343x, but Sargas remained a single star.

Has anyone ever seen the companion of Sargas:question:

Clear Skies
Joe

[Saturnine]

Hi Joe
Theta Scorpius is not listed in the Cambridge Double Star Atlas though it is marked as a binary on the maps. Also is not listed in the Night Sky Observers Guide, vol2.
It is marked and listed in Stellarium with the same details that you mention, so that and Sky Safari may get their info from the same source. Haven't checked with the Washington Double Star Catalogue yet, which is the definitive source for double ( multiple ) star information. You may want to search through their archives for any recent measures for Theta .

[EpickCrom]

Hi Jeff and thanks for the information :thumbsup:

I've been researching deeper on Sargas and it does appear to be listed as a double in error. I will be downloading Sky Safari Pro 7 soon so will check if this error has been rectified.

Clear Skies
Joe

[Robh]

Hi Joe,

The WDS Catalogue lists it as a double twice with magnitudes around 2 and 5.3 wth the same coordinates. However, it gives two separations for the pair as 0.3 and 6.5 arcsecs - seemingly two separate doubles. I would say that the correct separation is 0.3 arcsecs and that is why you can't split the pair.

It is likely the error is by the WDS crew. Not sure how that could happen as the separation has been measured at least twice.

SkySafari is just reading their error.

Regards, Rob

[EpickCrom]

Hi Rob.

Gee whizz, if it's 0.3" separation then it is really a tough split! I have an incoming 14 inch dob, but 0.3" is right at its limit. Sargas may need at least a 20 inch with super steady seeing to resolve. Thanks for your input :thumbsup:

Clear Skies
Joe