AE 118

Does Intergalactic SETI Make Any Sense?

The Breakthrough Listen project is proposing to extend its search for artificial radio and optical signals to include the 100 nearest galaxies.

The 70-metre radio telescope at Yevpatoria, Crimea

The 70-metre radio telescope at Yevpatoria, Crimea

But should we expect to find a beacon from a technological civilisation that is bright enough for us to detect over intergalactic distances?

The Andromeda Galaxy, number 31 in Messier’s catalogue, will be a good test case. It is the brightest of those shown within the 100 nearest galaxies, hence is presumably the largest, has a good line of sight from the Solar System, and is only one quarter of the distance of the most distant of the 100 to be observed in the Breakthrough Listen programme. It is closely similar to our own galaxy. If we can’t find extragalactic aliens in M31, we’re not likely to find them anywhere else.

Let’s ask what sort of transmitter power levels are expected of our alien pen-friends…

Read the full post on the Astronautical Evolution website.


AE 117

SETI and Sanity

What are the chances for Breakthrough Listen?

On 20 July 2015, Russian entrepreneur, venture capitalist and physicist Yuri Milner announced that he was putting $100 million over ten years into the search for extraterrestrial intelligence (SETI) in the form of two initiatives: Breakthrough Listen and Breakthrough Message.


With such a major injection of funding, SETI science will receive a tremendous boost. People the world over will be inspired to look up at the skies, and those elusive beacons announcing the presence of ET will surely soon be found. What’s not to like?

Agreed: any project which spreads public awareness that humans are a very small part of an overwhelmingly vast universe is to be applauded. We need that perspective when addressing mundane problems on Earth, if those problems are not to overwhelm us.

But what about the specific search for beacons or signals from alien civilisations which are aimed at attracting our attention? Is it in fact reasonable to expect any to exist?

Read the full post on the Astronautical Evolution website.