For decades researchers have observed signals from space in an effort to detect extraterrestrial communication. Somewhere buried in the far-off heavens perhaps another form of life was desperately looking for cosmic cousins ... maybe by using beams of electromagnetic radiation.
There are some people who think pulsars may indicate a form of alien communication. These stars regularly emit electromagnetic radiation every few seconds (or fractions of a second) as they spin, sending pulses of energy through the universe.
The regular pulsing is reminiscent of human-like communications. It's normally regular and patterned, though some occasionally experience brief glitches in their spin rate. So far, though, no signals have borne traits of complexity or structure that would give them meaning as language or messages.
Maybe someday another civilization will send us a greeting card via the stars. If they do, hopefully we're advanced enough to understand their sentiments.