From Wikipedia.
Voyager 1 – Wikipedia, the free encyclopedia: The Voyager 1 spacecraft is a 722 kg (1,590 lb) space probe launched by NASA on September 5, 1977 to study the outer Solar System and interstellar medium. Operating for 35 years, 6 months, and 16 days as of 21 March 2013, the spacecraft receives routine commands and transmits data back to the Deep Space Network. At a distance of about 123 AU (1.840×1010 km) as of November 2012, it is the farthest man-made object from Earth. It is still unclear whether the new region is interstellar space or an unknown region of the Solar System.
Think about how far away from earth that thing is (over 7 billion miles). And it is using technology from over 35 years ago. How do we even get signals from it?
Again from Wikipedia.
“The radio communication system of Voyager 1 was designed to be used up to and beyond the limits of the Solar System during the extremely long flight of this space probe. The communication system includes a 3.7 meter diameter parabolic dish high-gain antenna (see diagram) to send and receive radio waves via the three Deep Space Network stations on the Earth. These modulated waves are placed in the S-band (about 13 cm in wavelength) and X-band (about 3.6 cm in wavelength) which provided a bit rate as high as 115.2 kilobits per second when Voyager 1 was at the distance of Jupiter from the Earth, and many fewer kilobits per second at larger distances. When Voyager 1 is unable to communicate directly with the Earth, its digital tape recorder (DTR) can record up to 62,500 kilobytes of data for transmission at another time.”
You read that right, a tape recorder.
And how much power do those radios put out?
HowStuffWorks “How do the Voyager spacecraft transmit radio signals so far?”: The two Voyage spacecraft certainly have had an amazing track record. They were sent to photograph planets like Jupiter, Saturn and Neptune and have just kept on going past the outer edge of the solar system. Voyager 1 is currently over 7 billion miles (about 11 billion kilometers) away from Earth and is still transmitting — it takes about 10 hours for the signal to travel from the spacecraft to Earth! The Voyager spacecraft use 23-watt radios. This is higher than the 3 watts a typical cell phone uses, but in the grand scheme of things it is still a low-power transmitter. Big radio stations on Earth transmit at tens of thousands of watts and they still fade out fairly quickly.
And from NASA, I love this.
“The Voyager mission today presents an unequaled technical challenge. The spacecraft are now so far from home that it takes nine hours and 36 minutes for a radio signal traveling at the speed of light to reach Earth,”said Ed B. Massey, project manager for the Voyager Interstellar Mission. “That signal, produced by a 20 watt radio transmitter, is so faint that the amount of power reaching our antennas is 20 billion times smaller than the power of a digital watch battery … “
Mind-blowing.
Related links:
Voyager over the “heliocliff,” but Solar System transition mysterious
Voyager 2 Celebrates 35th Birthday, Becomes NASA’s Longest Space Mission
What Is on Voyager’s Golden Record? – Smithsonian
NASA’s Voyager 1 spacecraft nearing the edge of solar system, entering interstellar space
Voyager Probes Aim For Interstellar Space, Four Decades Of Travel : All Tech Considered : NPR