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Old 13-06-2021, 11:19 PM
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Atmos (Colin)
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Join Date: Aug 2011
Location: Melbourne
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Been digging through the DR3 archive and from what I can figure, there is a star in that region that has a parallax of 5.2 was (milliarcseconds) which equates to about 627 light years from us. I've been digging through images on the interwebs trying to find whether it is parallax but it's been a struggle.

And after spending an hour or two digging into Hubble Legacy Archive I've managed to track down the offending star. From counting pixels it has a movement of 1.11 arcseconds (~22 pixels at 0.05 arcsec/pixel) between 2002-04-05 19:13:39 & 2002-10-09 08:15:15.

So yes, it is definitely parallax.... Or is it....

Just as an FYI, I've been writing this one post for a couple of hours now so as another discovery... I was tracking the wrong star
I'm back on the stellar motion band wagon! What has been bugging me for a little while is that the DR2 stars were seeming to be before 2002 position as I have been comparing 2002 & 2013 images from Hubble. Then... BAM... It occurred to me that I was possibly using the DR2 catalog in J2000 and not current date so I recreated the time stamp for 2020 and damn near every star has moved compared to the 2000 time stamp.... DR2 catalog in PI takes into consideration proper motion.
Between 2002 and 2013 there is a 1 arc second movement so it is about 0.1 arcseconds per year.
In one of my previous posts I mentioned that it appeared that in the blue channel that the smaller star very close to the main mover was moving a little bit.... Well... it is! It had moved ~0.12 arc seconds between when Chart32 had taken their image and when I did.
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