koposov on 13-Jan-2015 13:50:26 GMT about Ross 905
The current position shown by Simbad is incorrect by a bit more than 1 arcseconds. It is caused by not using the Hipparcos positions but by using UCAC4 positions instead. Here is the comparison of Hipparcos vs UCAC4 J2000 positions.
U4 : 11 42 11.177 +26 42 22.64
Hip: 11 42 11.094 +26 42 23.65
Since the proper motions shown by Simbad are Hipparcos based, my suggestion is to use Hipparcos positions as well. Also some recent observations confirm that Hipparcos based position is correct, while UCAC4 is not.
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View annotation on Ross 905 object