NASA mistakenly severs communication to Voyager 2

Re:NASA mistakenly severs communication to Voyager 2 by Dylan16807 on Monday July 31, 2023 @03:30PM (#36947605)

So other people talked about how it does track, but there's another thing to note here.

"The high-gain antenna has a beamwidth of 0.5° for X-band, and 2.3° for S-band."

At 130-150 AU, the earth is always within about 0.4° of the sun. Since commands are sent on S-band, pointing directly at the sun gets a pretty good signal.

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Re:NASA mistakenly severs communication to Voyager 2 by mcv on Tuesday August 01, 2023 @08:04AM (#36954950)

Is that signal not drowned out by the sun? Or are these bands where the sun doesn't do anything?

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Re:NASA mistakenly severs communication to Voyager 2 by Dylan16807 on Tuesday August 01, 2023 @03:21PM (#36961161)

If I can trust arbitrary estimates on stack exchange, the deep space network transmitters will be about equal brightness to the sun at frequencies near 2GHz when the 20signal is 10 Hertz wide. That would put the transmission rate in the ballpark of 10 bits per second, and the real number is 16 bits per second, so that seems to work out.

Being drowned out is harder than you might think. The maximum data rate of a weak signal is 1.4 x [bandwidth] x [signal-to-noise ratio]. If you transmit across a 200MHz band, and your signal is a million times weaker than the noise, you can do hundreds of bits per second.

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