A ring or sphere could, apparently, be stable if surrounded by the right sizes and gravities of other stars.

Of all Earth’s layers, the inner core is the most remote and mysterious. This solid sphere of iron and nickel is about 70% the size of the moon, with a radius of approximately 759 miles (1,221 ...

A sphere is a perfectly round solid figure. All points on the surface of the shape are the same distance away from the centre – we call this distance the radius. The formula for the volume and ...

The barge Ready is fitted with a powerful derrick for lifting and swinging over the side the two-ton sphere. Photograph from William Beebe This solid rubber hose held the telephone and the ...