[Physicist]

This is a very interesting graphic that shows the extent to which we've searched the universe for alien civilizations. Earth-like radio emissions represent the bottom edge of the graph; as you can see, we haven't even begun to search for them. As for civilizations that have transmitters the size of our largest dish (Arecibo) transmitting directly at us, we've only searched thoroughly out to about 100 light years. The galaxy is 100,000 light years across, and we live in a portion of it that is somewhat more rarefied than average.

[For reference, a "Type I" civilization would be roughly capable of transmitting a signal equivalent to all of the sunlight striking the Earth, 2x10¹⁷ Watts. A "Type II" civilization would be roughly capable of sending a signal equivalent to the power of the sun, 4x10²⁶ Watts. (I believe the canonical signal limits for these civilizations are given as 10¹⁶ Watts and 10²⁶ Watts.)]

[yendu bwam]

Very interesting and eye-opening graphic. We have a long way to go on the SETI search!

[PatrickHenry]

That portion of the universe which I personally have explored is teaming with life.

[js1138]

The galaxy is 100,000 light years across, and we live in a portion of it that is somewhat more rarefied than average.

But is life (as we know it) possible in the denser portions of the galaxy?

[Aracelis]

Thank you for the ping and the graph!

[RadioAstronomer]

This is a very interesting graphic that shows the extent to which we've searched the universe for alien civilizations.

Thank you! :-)

[Quix]

But it seems to me to call the parameters on which the graphic is based . . . to call those parameters

valid parameters on ALL THAT IS

IS A REALLY FOOLHARDY SET OF ASSUMPTIONS.

We don't have sufficient perspective in any respects to firmly grip such a huge set of assumptions with any arrogance at all, much less 'sanity' compared to say . . .

God's perspective.

We don't even know where the curtains are, much less what's behind those unknown curtains.