how will the earth come to an end?

The sun will burn out, but not for another several billion years. But before that, in about 2 billion years the sun will start to expand into a red giant and broil the Earth.

The black hole at the centre of the galaxy is no threat to us, since its over 25,00 light years away and we aren't moving towards it - our solar system is orbiting the galactic centre and so we will never get any closer to it.

An asteroid or comet could certainly end the world (or at least most life on it), but there is none known to be an immediate threat to us (the closest possible threat is Apophis which could hit us in 2036 but the odds are 1 in 45,000).

An asteroid or some other large rock could indeed come crashing in and obliterate some or most of the planet.

The sun will, as others have said eventually use up it's fuel, expand and our planet will heat up, oceans will evaporate and eventually be consumed by the sun.

Long before this we will need to have found another place to call home somewhere else, or at least send enough humans outbound to another star system with a known planet capable of sustaining human life.

There are multiple ways that the earth can come to an end. Here are a few:

- as the sun dies, it will increase in size and vaporize the earth and nearby planets.

- a large celestial object will impact the earth.

- widespread nuclear war

- the scenario in the Revelations section of the Bible will come true

- the earth's orbit or spin or tilt can change, thereby creating severe weather conditions that can't sustain life as we know it.

Whichever method occurs first is the method that will end the earth. However, I don't think we have a way of determining which method will occur first.

there are many reports that say asteroids might eventually hit us, if it is the sun however we will all be dead by then (meaning people alive today) as it still has a long way to go before it burns out

The sun will run out of hydrogen and start using helium 5,000,000,000 years from now. That will do it.

Before that, we could get whacked by a nearby supernova or get hit by a rock. Since Andromeda is heading this way, who knows, we might even get whacked by a star.

read revelations in the bible