Sound is a mechanical wave. Sound propagates by oscillating the medium (matter) through which it travels. A vacuum is devoid of matter, so sound cannot propagate through a vacuum.
Light and heat, however, are electromagnetic (EM) waves. EM waves are electromagnetic disturbances that propagate in electric and magnetic fields.
An electromagnetic wave is an electric and magnetic disturbance that propagates through space (even a vacuum) at the speed of light ... No medium is required! (Robert Merlino PhD, University of Iowa)
Both electric fields and magnetic fields can exist in a vacuum. So heat and light can (and do) travel through vacuums.
An example of this is the heat and light our planet receives from the sun which travel through the vacuum of space.
Sound, on the other hand, is confined to our planet. Sound can propagate through the atmosphere (because the atmosphere is full of gaseous matter), but not beyond it into the vacuum of space.
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