What more can happen for the end of the humans?
This has been the subject of many documentaries, many of which are based on scientific observations and associated assumptions of the past in the rocks and out in space. Some are outright bizarre imaginings of people.
The Discover Magazine article about this topic lists several possibilities, including the following examples that scientists have evidence of causing mass extinctions in Earth's geological history (note: this is not an exhaustive list):
An asteroid/comet impact - which is the widely accepted theory of the cause of the KT extinction event that wiped out 70% of life 65 million years ago, including most of the dinosaurs.
Gamma ray burst - which some scientists hypothesise caused a mass extinction at the end of the Ordovician period, around 440 million years ago.
Mass volcanism - such as the what is thought by many scientists to have caused the phenomenally bad extinction event (over 90% life forms extinct) at the end of the Permian period (around 250 million years ago)
It should be noted that some extinction level events are not one single event and some are not sudden - for example, the extinction event at the end of the Permian ('The Great Dying")is theorised to have had multiple causes - volcanism, impact, methane clathrate release etc and the extinction occurred in pulses separated by thousands of years.
Other causes could include:
- Collisions with rogue planets
and so on.
The end of the Earth and the end of a habitat that can support life are 2 different things. The Earth will not be able to support life as we know it for 4 billion more years.
The sun is slowly heating up, and estimates are that in 500 million years, the Earth will be too hot to support life. That being said, life is resilient, and who knows what evolutionary changes might occur that would allow life to survive 500 million years from now. After all, the Sun heating up will be such a gradual process that evolution could most definitely keep up with it.
Then there is the fact that in 500 million years, even if we aren't destroyed by cataclysm, humans as we are today won't exist. We will have evolved into something else that wouldn't even remotely resemble humans. Probably Morlocks.
Technology also might allow us to escape our solar system and colonize across the universe.
Read "Death From the Skies!" by Phil Plait. His list is quite comprehensive, going into what can kill humanity, what could destroy all life on Earth, and what could destroy the Earth itself. I don't have my copy on me at the moment, but IIRC he goes into what damage a meteor of various sizes will do.