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Sirius A & B – the Pup revealed.
Hello,
Although the seeing wasn’t too cooperative earlier this morning (11th Nov 2008), nor were the clouds, I managed to grab some images of Sirius that also revealed the position of the Pup, Sirius B.
Due to the poor 5/10 seeing, the image was generally quite unstable, so to remove any potential seeing or system artefacts, I rotated the CCD camera CCW ( approx 0, 90, 180 & 270 degrees) between successive shots, in an attempt to place the Pup in-between the diffraction spikes.
Images taken with a Mewlon 180 F12, TeleVue x4 PowerMate and DMK31AF04 CCD camera. The apparent difference in size of the stellar disc of Sirius A between frames is mainly due to my experimenting with exposures of 1/5 sec and 1/15 second and Gain of 600 and 850. Gamma was set at 18.
Cheers
Dennis
Sirius, aka Alpha CMa, Magnitude: -1.46.
AB: -1.44+8.5 mag
PA 95° Sep 8.38" (2008.9)
Sirius is 9 times more brilliant than a standard first magnitude star.
B is first white dwarf ever discovered; predicted by Bessel (1844) on basis of orbital motion of Sirius, it was first seen by Alvan Clark in 1862, and its peculiar high temperature, small size and great density established by W. Adams in 1925.
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