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Is it true that it would take a life time to leave our galaxy?

Answer 1

Yes and no...

If you were able to construct a spacecraft that accelerated constantly at about #1#g for #14# years (ship time), then decelerated constantly at about #1#g for #14# years (ship time), then that would be sufficient to not only leave our galaxy, but get to the neighbouring major galaxy, the Andromeda Galaxy, approximately #2.5# million light years away.

One downside is that by the time you could return (another #28# years of ship time), a total of about #5# million years would have passed on Earth. So not only would all your ground support team have died, but humans might have evolved into something else or at least become extinct in the meantime.

What if our modest objective was to simply leave the galaxy?

We are about #25000# light years from the centre of our galaxy, which has radius about #50000# to #60000# light years. In other words, we are about halfway out, with the nearest point on "the rim" (so to speak) about #25000# to #30000# light years away. So, regardless of how hard we try, it would take at least #25000# years of ground team time for us to reach the edge of the Milky Way, since it is (probably) not possible to travel faster than light.

Ship time could be much reduced, similar to the Andromeda trip, but it's still not very useful.

What about just travelling out of the plane of the galaxy? It's relatively flat isn't it? Well yes, that would cut our journey down to a mere #500# or so light years, but that would still take at least #500# years of ground team time.

The challenge of protecting the ship from the effects of passing tiny particles, which could irradiate the entire ship and its occupants, is another drawback of traveling at a high speed.

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Answer 2

Clara Avalos

Yes, with current technology, it would take thousands of years to travel beyond our galaxy.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.