Power Point Viewgraphs for recent public presentations at
the Fiske Planetarium
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The Birth of Stars and Planets
Wide field images from ground based telescopes and high
resolution images from the Hubble Space Telescope
reveal parsec scale jets, and nascent proto-planetary disks
that are being evaporated by the light of nearby massive young
stars. Star foramtion research is begining to shed light on the
formation of planetary systems.
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The Quest for Life Beyond the Solar System.
How common are extra-terrestrial civilizations? What type of signals might
such civilizations produce? Can we detect such signals? Our current
understanding of star and planet formation indicates that roughly 1% of
forming stars may eventually produce habitable environments.
SETI searches for extraterrestrial civilizations can look for three
types of signal:
[1] BEACONS established for the explicit purpose of being detected.
However, such beacons must radiate at least 10^{12} to 10^{16} Watts to
be visible to current SETI searches. I argue that energetics and economics
makes it VERY UNLIKELY that any civilizations establish such beacons.
[2] Evesdroping on INTERSTELLAR COMMUNICATIONS. It is argued that advanced
spacefaring civilizations migrate their internal communications to very
high frequencies (x-rays and gamma rays) and utilize gravitational lensing
by stars to concentrate their broadcast power. Detecting such signals
will next next to impossible.
[3] LEAKAGE SIGNALS such as those we unintentionally launch into space.
Our own civilization radiates about 10^8 Watts. This is our best chance
to succeed with SETI.
I derive a relationship between the lifetime of a extra-terrestrial
civilizations in the radio broadcasting state and the most likely minimum
distance to such a civilization. If the duration of the radio broadcasting
phase is only 100 years, then the nearest civilization is likely to
be at least 10,000 light years away. However, detecting a leakage signal
from such a civilization will require a radio telescope with a collecting
area of at least 100 square kilometers.
Therefore, none of the current SETI searches are likely to succeed.
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