As hard as it is to imagine the size of Antares compared to earth (comparative as the earth is to a house, maybe?) try to image the size of the smallest planet that probably revolves around that monstrosity!
QUOTE
Antares is a class M supergiant star, with a diameter of approximately 1.33 × 109 km. I.e., if in place of our sun, it would slightly more than encompass the average orbit of Mars.
(wikipedia)
In other words, the circumference of that baby is bigger than Mars orbit (which means we would be very toasty in the winter time if this behemoth decided to move into the neighborhood. Think about that next time you complain about it being too cold or too hot outside! Ouch! There goes the property values!)