I've built this piece of code...(javascript)

Now we have a red sphere on the screen...the question is
how to make it spinning around?

var camera, scene, renderer,
mouseX = 0, mouseY = 0;

var geometry,material,mesh;

init();



function init() {



// Camera params : 

// field of view, aspect ratio for render output, near and far clipping plane. 

    camera = new THREE.Camera( 75, window.innerWidth / window.innerHeight, 1, 1000 );



// move the camera backwards so we can see stuff! 

// default position is 0,0,0.

camera.position.z = 300;



// the scene contains all the 3D object data

    scene = new THREE.Scene();



// and the CanvasRenderer figures out what the 

// stuff in the scene looks like and draws it!  

    renderer = new THREE.CanvasRenderer();

    renderer.setSize( window.innerWidth, window.innerHeight );



// the renderer's canvas domElement is added to the body

    document.body.appendChild( renderer.domElement );



    // creating shapes

makeShapes(); 



// add the mouse move listener

document.addEventListener( 'mousemove', onMouseMove, false );



// render 30 times a second (should also look 

// at requestAnimationFrame) 

setInterval(update,1000/30); 



}



function update(){



updateParticles();



// and render the scene from the perspective of the camera

renderer.render( scene, camera );



}



function makeShapes() { 



    // create a sphere shape        

    geometry = new THREE.SphereGeometry( 50, 16, 16 );



    // give a shape red color

    material = new THREE.MeshLambertMaterial({color: 0xFF1111});    



    // create an object

    mesh = new THREE.Mesh( geometry, material );



    mesh.position.x = 0;



    // add it to the scene

    scene.addObject( mesh );

}







function updateParticles(){



}



// called when the mouse moves

function onMouseMove( event ) {



// store the mouseX and mouseY position 

mouseX = event.clientX;

mouseY = event.clientY;

}