There is another, slower method of sending
messages to space, which is to physically send
them on board spacecraft.
This plaque was attached to the Pioneer spacecraft
which were launched in the early 1970s.
Pioneer 10 is now more than 80 AU from the Earth
and unfortunately has run out of power (as
of a couple of years ago) so
we are no longer communicating with it. Nevertheless,
the message is still on its way to Aldebaran,
where it will arrive in around 2 million years.
The last communication with Pioneer 11 was in
1995, after which time the spacecraft's attenna
was no longer pointing at the Earth and had
no more onboard power to change its orientation.
It will arrive at a star in the constellation
Aquila in around 4 million years.