Answer :
A beam of light (travelling at the speed of light) would take 65 years to go and 65 years to come back from aldebaran, i.e. 130 years. You can send and receive a radio message (travelling at the speed of light, being electromagnetic radiation) taking so 130 years.
Light is electromagnetic radiation, which travels at the speed of [tex]3 \times 10^8[/tex] m/s in a vacuum. The light is the visible portion of the spectrum that cane is perceived by the human eye.
The message or information will take 130 years to send back the signal.
The light rays travel fastest in the vacuum. The light rays as given will take 65 years to reach the star Aldebaran. The Aldebaran when receiving the information will send back the signal, that would take 65 years again to reach the earth.
The time required by the beam of light to reach the star Aldebaran and revive it to be sent back to the earth will take 135 light-years.
Thus, the correct answer is 135 light-years.
To know more about light, refer to the following link:
https://brainly.com/question/13349357
