For those curious about the nomenclature, the reason the star is called "VY Canis Majoris" is that it is a variable star. All variable stars are denoted by either a single letter, two letters, or the letter "V" followed by a number. Hence V382 Carinae, VV Cephei, RR Lyrae etc. (interestingly, RR Lyrae is also the name of a sub-classification of variable star ).
And while saying that VY CMa only goes out to Saturn may be underwhelming to some, to me that is astounding. When you realize the r^3 dependence of volume, holy , something going out to Saturn isotropically is ridiculously big. Really, in one sense, there is nothing bigger we know in the universe. Space is just so empty. Even in a galaxy (not taking into account spaces between galaxies, let alone the voids) there is just so much empty space. So for a volume of space with a radius of 9 AU or whatever Saturn is to be filled with matter (although I imagine that it would be remarkably tenuous)...that is ridiculous.
To illustrate just how empty even "filled space" is, think about this. When M31 and our galaxy "collide" in a few billion years, odds are that no stars at all will collide. This is a collision of some trillion stars...and not one collision...it's remarkable, and should give one an idea of just how empty "filled" space is. Now just imagine how empty empty space is.
The universe really is remarkable and fascinating.
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"For thousands of years humans were oppressed - as some of us still are - by the notion that the universe is a marionette whose strings are pulled by a god or gods, unseen and inscrutable." - Carl Sagan
Freedom consonant with responsibility.
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