As most of you know by now, once you have finished the Halo 3 campaign on legendary and you sit through the credits you get treated to a special video that shows master chief and Cortana on a ship in deep space. The screen goes black for a second and then the ship is seen moving closer and closer to some kind of planet. The music rises and you are brought back to the main menu of halo. What's so special about this? Well, let's look at Halo: Reach launch trailer.

The trailer opens with dramatic music and text that reads: From the beginning you know the end. Then a planet appears. The planet looks like it's earth. Then explosions start on the planet's surface. There is much radio chatter and yelling. The screen then shows the Halo reach logo and the trailer ends.

Now take a look at these 2 images. On the left is the Halo 3 legendary ending planet, and on the right is the Halo Reach trailer planet.

The planet's are the same! This means that Master Chief and Cortana are safely landing on earth just in time for Halo 4. Of course there are many other explanations for this, but I just decided to go with the most likely.