HST photometry of the stars near the center of PN NGC 650
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چکیده
Colours and magnitudes of the central star of NGC 650 and its two companions have been obtained from HST images. The spectral types of the companions, which have been deduced from the colours, suggest a probable distance to the companions of between 5 and 6 kpc. Using the spectral and photometric characteristics of the central star, which are very similar to the very well studied PN PG 1159, we show that its distance is probably close to 1.2 kpc. Thus it appears unlikely that the central star is physically related to the two visible companions .
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تاریخ انتشار 1998