Posted: Dec 22, 2016 5:59 pm
Sendraks wrote:solazy wrote:
SETI have found nothing. So they start complaining they are looking at the wrong part of the sky.
They're complaining?
SETI has barely been active for any time at all. The length of time it could takes for our signal to reach anywhere capable of hearing it could be hundreds of years. Which would mean hundreds of years before we get a response. Or we could catch onto a signal from somewhere else in the galaxy which, depending on its source, could've taken hundreds of years to reach us. We could beam a message back and it will reach it target in hundreds of years. By which point there may be no one left to receive it and we might be gone before we ever reach a response.
SETI are not complaining they are looking at the wrong part of the sky, because that would suggest anyone has an inkling as to which part of the sky might be more likely to receive a message than any other part.
SETI does not depend on getting a reply, only on distant civilizations starting well before ours, leaving time for their signals (deliberate or otherwise) to reach us.
EDIT: There is a power issue: the ony reason we can detect the emissions from distant stars above the background noise is that stars are extremely powerful radio sources, so our aliens would indeed need to go to great lengths to harness the power of a star if they were to succeed in sending us a message from a distance much greater than the nearest few stars.