Far from it. After the Voyagers completed their tours of the outer planets in the 1980s, giving humanity its first real look at Jupiter, Saturn, Uranus, and Neptune, they continued on to the outer reaches of the solar system. In August 2012, Voyager 1 left the system entirely, emerging from inside the protective bubble formed by the sun’s wind and exiting into interstellar space. Voyager 2 is on its way out; the spacecraft is currently coasting through the heliosheath, the outermost layer of the sun’s bubble. Voyagers 1 and 2 are currently about 13 billion and 10 billion miles from Earth, unfathomable distances that mean little more to us terrestrials than giant numbers on a page. [...]
The Voyagers transmit data to Earth every day. The spacecraft collect information about their surrounding environment in real time and then send it back through radio signals. Voyager 1 data takes about 19 hours to reach Earth, and signals from Voyager 2 about 16 hours. (For comparison, it takes the rovers on Mars 20 minutes on average to call home.) The signals get picked up by NASA’s Deep Space Network, a collection of powerful antennae around the world that communicate with dozens of missions. [....]
The DSN spends between four and seven hours per day listening for the faint pings of the spacecraft. The power of the transmitter aboard the spacecraft is similar in wattage to that of a refrigerator light bulb. But the DSN is sensitive enough to hear its messages, and, if necessary, can become even more sensitive. If Earth needs a bigger ear for Voyager in the future, the DSN can make its facilities work as a single array, with more collecting power.
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