SETI

Question 1

Main methods used in SETI

Answer 1

-EM messages to communicate

-optical SETI
-uses optical wavelengths
-modern telescopes can produce a pulse much brighter than the sun fro very short periods
-problem: universe is noise in the optical
-solution: look on very short timescales
-most background sources don’t emit strongly at this rate

-search for extraterrestrial artefacts
-look for alien probs
problem: very dark with low IR emissions so hard to find
-requires intense searching

-Physical messages (biased data-could use maths equations)
-voyager records

Question 2

An example of efforts to communicate with extraterrestrial intelligence

Answer 2

Project Ozma in 1960

-turned radiotelescope towards 2 stars
-150 hours of observation
-northing was found - silence

Question 3

What is the Fermi paradox?

Answer 3

where are the aliens?
-the galaxy should be colonised since there should be older life-forms than on earth that are intelligent

Question 4

solutions to the Fermi paradox

Answer 4

-observing from afar
-they can’t get here (too far and don’t have the technology)
-all civilisations destroy themselves

Question 5

What is the Drake equation?

Answer 5

an equation to estimate the number of civilisations out there

issue-by the time we answer some of the terms, we would have quite a good idea of the answer

Question 6

terms in the drake equation

Answer 6

-average rate of star formation in our galaxy
-the fraction of those stars that have planets