How many photons are received per bit transmitted from Voyager 1? (physics.stackexchange.com)

Article summary

The article discusses the number of photons received per bit transmitted from Voyager 1, with the actual number of photons received being around 1500 or 400 per bit. The calculation of this number is based on the spacecraft's transmission power and the distance between the spacecraft and Earth. The discussion revolves around the Shannon limit and how it affects the communication with Voyager 1. The spacecraft's power is decreasing, which will eventually limit its ability to transmit signals back to Earth.

Main themes

• Voyager 1 signal strength
• Shannon limit
• Space communication
• Photon transmission
• Signal processing

What commenters say

• The Shannon limit is a fundamental limit that cannot be directly overcome, but there are ways to receive information from further away, such as using a bigger dish or reducing the bitrate.
• Increasing the receiving dish size or using multiple dishes can improve the signal strength and allow for communication over longer distances.
• Error correction and encoding can help to reduce the effects of noise and allow for more reliable communication, but they cannot overcome the Shannon limit.
• The distance at which communication with Voyager 1 will become impossible due to the Shannon limit is estimated to be around 961 astronomical units, which is much closer than the distance to the nearest star.
• Some commenters suggest using relays or amplifiers to extend the communication range, but this would require significant technological advancements and infrastructure development.
• The power of the Voyager 1 spacecraft is decreasing, which will eventually limit its ability to transmit signals back to Earth, regardless of the communication technology used.
• The calculation of the number of photons received per bit is based on the spacecraft's transmission power and the distance between the spacecraft and Earth, and is estimated to be around 1500 or 400 per bit.