According to the theory of special relativity, it is not possible for an object with mass to reach or exceed the speed of light in a vacuum. As an object with mass accelerates towards the speed of light, its relativistic mass increases, requiring an infinite amount of energy to reach the speed of light. Therefore, it is not meaningful to speak of an object's speed when it reaches the speed of light.
Furthermore, as an object approaches the speed of light, time dilation and length contraction effects become significant. From the perspective of an observer moving at a constant velocity relative to the object, time would appear to slow down for the object, and its length would appear to contract along the direction of motion. However, it is important to note that these effects are experienced from the perspective of the observer and not the object itself.
In summary, an object with mass cannot reach or exceed the speed of light, and discussing its speed at the speed of light is not meaningful within the framework of special relativity.