(solved) CircleGeometry not visible from certain angles?

[atomic locust]

I have a circle lying on the XZ plane
Its basically the default CircleGeometry with an X-rotation

function whyIsntThisWorking(r: R) {
    const mesh = new Mesh(
        new CircleGeometry(5),
        new MeshBasicMaterial({
            color: 0xffffff,
        })
    )

    mesh.rotateX(-Math.PI / 2)

    r.scene.add(mesh)
}

but its only visible when looking from above, and not from below
this happens with both PerspectiveCamera and OrthographicCamera

Any idea where I messed up?

(happens for everyrotation / lighting, just at diff camera angles)

ik i could just use a cylinder geom but curious why this happens

[atomic locust]

oh saw this in #general
#general message

and setting it to doubleside worked