Not unless they needed to do a flyby of our sun for a gravity assist change of trajectory. Or to pick up fuel, say by skimming low over our sun and picking up hydrogen fuel from the sun, can think of a few scenarios where they might want to pass close by stars from time to time.
But to get an idea of how difficult it is to hit a solar system - density of stars is about 1 star every seven cubic light years in vicinity of the sun.
Diameter of our solar system, out to pluto is 5.5 hours
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So, suppose you were traveling a distance of 1000 light years, random direction, what is the chance that another star is within 5.5 hours of your flight path?
Well 5 hours is 0.00062743773 of a year. To find volume, use 1000*pi * r^2, I make it 0.0012367762 stars on average within that volume of space.
So - not that likely that you hit a star.
Travel for a million light years, and the average number of stars within that volume of space is more than 1.
So let's suppose our ET is a frequent traveler in the galaxy in regions with similar stellar density to the sun, and with an extremely long lifetime, traveling at random in straight lines, (or indeed curved path, doesn't matter so long as it is not avoiding or targeting or influenced by stars) - at close to light speed
Well ET would pass closer to a star than Pluto on average once every million years or so.
Gives a rough idea anyway.
But to get an idea of how difficult it is to hit a solar system - density of stars is about 1 star every seven cubic light years in vicinity of the sun.
Diameter of our solar system, out to pluto is 5.5 hours
Archive of Astronomy Questions and Answers
So, suppose you were traveling a distance of 1000 light years, random direction, what is the chance that another star is within 5.5 hours of your flight path?
Well 5 hours is 0.00062743773 of a year. To find volume, use 1000*pi * r^2, I make it 0.0012367762 stars on average within that volume of space.
So - not that likely that you hit a star.
Travel for a million light years, and the average number of stars within that volume of space is more than 1.
So let's suppose our ET is a frequent traveler in the galaxy in regions with similar stellar density to the sun, and with an extremely long lifetime, traveling at random in straight lines, (or indeed curved path, doesn't matter so long as it is not avoiding or targeting or influenced by stars) - at close to light speed
Well ET would pass closer to a star than Pluto on average once every million years or so.
Gives a rough idea anyway.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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