What radio signal have NASA transmitted to outside our solar system and what did they contain?
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3$\begingroup$ "Free food & slaves - planet #3". $\endgroup$– void_ptrJun 19, 2020 at 22:43
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1$\begingroup$ All radio waves with a high enough frequency that were emitted are outside of the solar system, or at least, will be. $\endgroup$– Star ManJun 19, 2020 at 23:35
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$\begingroup$ List of interstellar radio messages en.wikipedia.org/wiki/List_of_interstellar_radio_messages $\endgroup$– A. RumlinJun 20, 2020 at 15:45
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$\begingroup$ @A.Rumlin Cool! $\endgroup$– user36677Jun 20, 2020 at 17:27
1 Answer
Every command sent to a satellite or space probe from Earth continues traveling, forever.
At some point it becomes so weak it's impossible to interpret, of course, but NASA routinely receives data transmitted from the two Voyager spacecraft, both of which are now on the outer side of the Solar System's boundary shock, and both of which, due to aging of their onboard power sources, now transmit at only a few watts (directional transmission helps a lot, but even so, large dish antennas are required on the ground).
Similar equipment to the large dishes at Very Large Array, Green Bank, etc. could receive commands intended for, say, a Mars orbiter to distances well beyond the heliopause.
There have been intentional transmissions toward other star systems, as well (at least one globular cluster was targeted by a strong transmission from Arecibo, though that signal will not arrive for another few thousand years), but none were initiated by NASA. NASA, as far as I know, adheres to the United Nations protocol prohibiting attempting contact with extraterrestrials without the consent and supervision of the United Nations.