You don't have to be the size of a planet to do some space-time warping.

Large objects such as the Sun and planets aren't the only masses that warp the fabric of space-time. Anything with mass—including your body—bends this four-dimensional cosmic grid. The warp, in turn, creates the effect of gravity, redirecting the path of objects that travel into it. The strength of gravity depends on the size of the space-time warp. A large object with little mass creates a smaller distortion than a tiny object with a huge mass.

The 4th Dimension

3-D Space

Space expands out from each of us in three dimensions—up and down, side to side and front to back—to the far reaches of the universe. But Einstein showed that space doesn't exist independent of time.

4-D Space-Time

Like a filmstrip, "slices" of time show a rider on a horse galloping through 3-D space. Each "slice" also pinpoints an exact moment of the event as it occurs through time. Together, space and time make up the four-dimensional arena in which all things exist.