Communion Of Dreams

“You’re oversharing again, Earth.”

Seth Shostak, on the topic of how to introduce ourselves to our neighbors:

A better approach is to note that the nearest intelligent extraterrestrials are likely to be at least dozens of light-years away. Even assuming that active SETI provokes a reply, it won’t be breezy conversation. Simple back-and-forth exchanges would take decades. This suggests that we should abandon the “greeting card” format of previous signaling schemes, and offer the aliens Big Data.

For example, we could transmit the contents of the Internet. Such a large corpus — with its text, pictures, videos and sounds — would allow clever extraterrestrials to decipher much about our society, and even formulate questions that could be answered with the material in hand.


While I still agree with Stephen Hawking on the idea of ‘active SETI’, I think that there’s merit in the idea of exposing other nearby civilizations to what we’re really like, warts and all. Because as soon as they decoded our transmissions well enough to understand the comments section of pretty much any major site on the web, they’d either completely wall off our solar system* and post warnings around it or just trigger our sun to go supernova. Either way, we’d never know what happened, and the rest of the galaxy would be safe …


Jim Downey
*gee, that’d make an interesting premise for a SF novel, doncha think?

A closing window.

The Fermi paradox is at the heart of Communion of Dreams – given what we know, where are the extra-terrestrials?

What do I mean “given what we know”? Well, the Drake equation has been a staple of science fiction (and at least part of the justification for SETI) for decades. Filling in the factors in the equation has always necessitated a lot of guesswork – the Wiki entry goes into that fairly well – but now we have more solid information on at least one of the more important components of the equation: how many terrestrial (Earth-like) planets are there in our galaxy?

Phil Plait has a good rundown on this, coming at the number from two directions, using the latest astronomical observations:

How many habitable planets are there in the galaxy?

By now you may have heard the report that as many as 1/4 of all the sun-like stars in the Milky Way may have Earth-like worlds. Briefly, astronomers studied 166 stars within 80 light years of Earth, and did a survey of the planets they found orbiting them. What they found is that about 1.5% of the stars have Jupiter-mass planets, 6% have Neptune-mass ones, and about 12% have planets from 3 – 10 times the Earth’s mass. This sample isn’t complete, and they cannot detect planets smaller than 3 times the Earth’s mass. But using some statistics, they can estimate from the trend that as many as 25% of sun-like stars have earth-mass planets orbiting them!

And what does that mean? Here’s the closing calculation from Plait:

2 x 1013 / 8000 = 2,500,000,000 planets

Oh my. Yeah, let that sink in for a second. That’s 2.5 billion planets that are potentially habitable!

How many of them would host indigenous life? How many of *those* would develop intelligent, technological civilization? There’s a nice interactive on the PBS site which allows you to play with this. Using that 2.5 billion number, but assuming that only half the planets which could support life will actually develop it, and that only 1% of those will develop intelligent life, and that only 10% of those intelligent lifeforms will develop technological civilizations capable of interstellar communication . . . you wind up with 125,000 such civilizations. You then have to make some assumptions about how long such a civilization would last, and what the likelihood would be that they would be around now (at the same time we are), but still . . .

I’ve complained previously that I worry that solid evidence of extraterrestrial intelligence will be discovered before Communion of Dreams makes it into print. That window is now closing. But you know, I really wouldn’t complain too much now if such evidence beat me to press.

Jim Downey

Everybody’s talking . . .

. . . about Stephen Hawking’s caution regarding contacting alien civilizations.

LONDON (AFP) – Aliens may exist but mankind should avoid contact with them as the consequences could be devastating, British scientist Stephen Hawking has warned.

“If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans,” said the astrophysicist in a new television series, according to British media reports.


THE aliens are out there and Earth had better watch out, at least according to Stephen Hawking. He has suggested that extraterrestrials are almost certain to exist — but that instead of seeking them out, humanity should be doing all it that can to avoid any contact.

* * *

Alien life, he will suggest, is almost certain to exist in many other parts of the universe: not just in planets, but perhaps in the centre of stars or even floating in interplanetary space.

Hawking’s logic on aliens is, for him, unusually simple. The universe, he points out, has 100 billion galaxies, each containing hundreds of millions of stars. In such a big place, Earth is unlikely to be the only planet where life has evolved.

It’s also hit a number of the big aggregating sites such as Huffington Post, BoingBoing, and MetaFilter, as well as popular science sites Bad Astronomy and Discover. The more intelligent comments/discussions get into such things as Fermi’s Paradox, the Drake Equation, and SETI, and debating the why of what would appeal to aliens about us.

Man, it really makes me wish that Communion of Dreams was currently in print. Because this is all stuff that I discuss, at length, there. The topic of alien contact is as old as science fiction, but it comes and goes in popularity – and right now it’d be great to have my book on the shelves of bookstores.

Ah well. Story of my life.

Jim Downey