Rob_K
28-09-2010, 11:13 AM
Never know what you can find in your images...
The other night I imaged a run-of-the-mill outbursting star V893 Sco and last night I double-checked its position using a Deep Sky Survey plate overlay, all pretty boring stuff (well, really boring). But something in the corner of the overlay caught my eye - while every other star (black dots on negative plate) was centered on my fuzzy blobs, one wasn't. Why? Checked the position in Aladin and it turns out the star is a 'high proper motion star', meaning it's moved on from where it was when the survey image was taken.
In the first image the star/survey mismatch is shown with the arrow-question marks. The circular inset shows the star, designated LHS 3169, and its direction of movement. V893 Sco is in the cross-hairs. Second image shows an actual pixel crop at L image size (Canon 400D, 200mm, 5 x 60 sec @ ISO 1600, F/5.6).
What really gets me I suppose is that you can find out all this stuff on the web, with the click of a mouse. Twenty years ago you couldn't. And not just the finding out & sourcing DSS plates, but the image manipulation. It's a great age to live in if you're interested in astronomy and it's getting better all the time! :D
Cheers -
The other night I imaged a run-of-the-mill outbursting star V893 Sco and last night I double-checked its position using a Deep Sky Survey plate overlay, all pretty boring stuff (well, really boring). But something in the corner of the overlay caught my eye - while every other star (black dots on negative plate) was centered on my fuzzy blobs, one wasn't. Why? Checked the position in Aladin and it turns out the star is a 'high proper motion star', meaning it's moved on from where it was when the survey image was taken.
In the first image the star/survey mismatch is shown with the arrow-question marks. The circular inset shows the star, designated LHS 3169, and its direction of movement. V893 Sco is in the cross-hairs. Second image shows an actual pixel crop at L image size (Canon 400D, 200mm, 5 x 60 sec @ ISO 1600, F/5.6).
What really gets me I suppose is that you can find out all this stuff on the web, with the click of a mouse. Twenty years ago you couldn't. And not just the finding out & sourcing DSS plates, but the image manipulation. It's a great age to live in if you're interested in astronomy and it's getting better all the time! :D
Cheers -