November 19, 2018

Astro-Event of the Week: Can You Spy Sirius B?

This week’s challenge is a tough one, and may deserve a re-visit or two over the coming decade  to yield success. Everyone knows that Sirius is this brightest star in the sky, but did you know that it has a tiny, elusive white dwarf companion? Tough to locate, this +8.7 magnitude object currently lies at an apparent separation of 9” arc seconds and growing. Usually, that wouldn’t be a tough split, except for the fact that bright Sirius A swamps it out by its -1.42 magnitude brightness! To spot it, you’ll need a telescope of at least 4” aperture, high magnification, and clear, pristine skies. Also, an eyepiece equipped with an occulting bar could prove helpful; the trick is to cover up the bright primary to the northeast while Sirius B lies to the left at a south western position angle.

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