Re: Nick's misquided notions about ID theory led him to an invalidconclusion

Cubist wrote: Among other things: SETI assumes that the senders
actually want to communicate with beings in other star systems, that
the senders have technology more-or-less equivalent to what we humans
have got, and that the senders think radio transmissions are a good way
to do it. None of these assumptions are *necessarily* reliable, of
course. But in the absence of *any* such assumptions, how the heck can
you figure out what you ought to be looking for?

Sharon: My father, *may he rest in peace*, saw the opening to the movie
"Contact" -- it appears scientific, the camera drawing away from Earth
and radio signals in space... right out to Hitler speaking and audio
fading out on morse code -- going back in time. I was amazed by the
computer animation -- but my Dad shrugged it off and told me that it
wouldn't happen. He never was one to explain a lot, but if my memory is
correct he explained the interference (i.e., Asteroid Belt and other
disruption in space?) would prevent radio signals and the like from
traveling and transmitted 'infinitely'. I didn't believe him at the
time, afterall, it was "Contact" written by Carl Sagan. My Dad was
lisenced by the FCC, advanced Ham Radio Operator lisence, and
understood something about Communications I didn't. He also spent years
selling and servicing satellite reception dishes / systems. A lot of
credentials in electronics / communications.

I have thought about the question -- could we receive signals from
intelligent life? (if it exists). How long has man had the technology
to communicate via space? The past century? We already know this planet
is *only* around four billion years old - - and it took 3.8 to get
where we are today. How much time for "evolved intelligent life" in any
other system to develop the technology to communicate? Of course we
had Christianity hindering the progress of scientists for centuries --
so perhaps another system "out there, somewhere" could have developed
means of communication. Yet, the speed of the waves would have to be
equal that of light -- and what signals they send out *today* -- might
reach us in 17 or 170 or 1700 years after transmission?

What are the chances?

Radio Waves
Radio waves are invisible waves of electricity and magnetism. Each
radio station sends out radio waves. They travel out from the station
something like water waves travel out from a splash in a pond. Water
waves travel slow, about 10 miles each hour. Radio waves travel very
fast, at 186,000 miles each second.
http://www.midnightscience.com/howxtal.html

The Speed of Light - Succeed in Physical Science
Since light travels so fast, it would normally be reflected back
through the ...
All electromagnetic waves, including visible light, travel at 186000
mi/sec ...
www.school-for-champions.com/science/lightspeed.htm


THE NEAREST STARS
Polaris ... transmission traveling at the speed of light . . . 360 to
820 years to reach earth.
Rigel ... transmission traveling at the speed of light . . . 900 years
to reach earth.
Vega ... transmission traveling at the speed of light . . . 25 years to
reach earth.<-- Maybe

There's not that many systems that close to us. Even if they are life
like us, "out there" the chances of their transmission reaching us, in
our life time -- or vis versa, is unlikely.

Alpha Centauri is the star system that is closest to the Earth. The
dimmest star in the system, Proxima Centauri (Alpha Centauri C), is the
closest star to us (other than our sun). The stars Alpha Centauri A and
Alpha Centauri B are close binary stars.

http://www.enchantedlearning.com/subjects/astronomy/stars/majorstars.shtml

If Betelgeuse were at the center of our Solar System, it would extend
beyond the orbit of Jupiter. It is 520 light-years from Earth.

Aldebaran is about 40 times as big as the Sun.

Alnitak (Zeta Orionis) is a star at the eastern end of the Orion's belt

Antares is a M1.5Iab variable red supergiant star that is about 520
light-years from Earth and is about 230 times as big as the Sun.

Arcturus is 34 light-years from Earth.

Capella is a multiple star system containing at least 9 stars. This
bright system is in the Northern Hemisphere, 45 degrees from Polaris
(the northern pole star); it is in the constellation Auriga. The two
brightest stars in Capella are a binary star system. They are both
yellow (like our Sun) with masses 2.6 times and 2.7 times that of the
Sun. One is 9 times as large as the Sun, the other is 12 times as
large. Each gives off roughy 78 times the light as the Sun. These two
stars are about 43 light years from Earth.

This young, bright, blue supergiant star is about 1,500 light years
away.
Deneb is about 60,000 times more luminous than the sun!

Polaris' distance from Earth has been estimated to be from 360 to 820
light years. At its brightest, Polairs is about 6,000 to 10,000 times
brighter than our Sun. It is the larger star at the end of the handle
of the Little Dipper (Ursa Minor). Polaris is also called the Lodestar
or the Cynosure.

PROXIMA CENTAURI
The closest star to us is the Sun. Other than that, the closest star is
Proxima Centauri, aka Alpha Centauri C (the dimmest star in the Alpha
centauri system). Proxima Centauri is about 4.2 light-years from the
Sun.

RIGEL
Rigel (beta Orionis) is the brightest star in the constellation Orion
and one of the brightest stars in the sky. It is a blue (very hot)
supergiant, over 60 million miles in diameter (almost 100 times bigger
than the sun). It is more than 50,000 times more luminous than the Sun.
It has an absolute magnitude of -7.1 and an apparent magnitude of
+0.12. It is over 900 light-years from Earth.

Sirius (meaning "scorching" in Greek), also known as the dog star, is
the brightest star in the sky (except for the sun). It is in the
constellation Canis Major (The Great Dog). Sirius is a main sequence
star that is about 70 times more luminous than the sun. It is about 8.6
light-years from Earth.

The Sun is a star at the center of our solar system. Our Sun is a
medium-sized yellow star that is 93,026,724 miles (149,680,000 km) from
Earth. Its diameter is 865,121 miles (1,391,980 km). At its core,
nuclear reactions produce enormous amounts of energy, through the
process of converting hydrogen atoms into helium atoms (nuclear
fusion). Its absolute
magnitude is +4.83. The solar mass is 1.99 x 1030 kg.

Vega is the 5th brightest star in the sky and is pale blue. It is about
25 light years from Earth. Its spectral type is A0Va. A disk of dust
surrounds Vega, from which planets might form. Vega, together with
Deneb and Altair form the Summer Triangle.
http://www.enchantedlearning.com/subjects/astronomy/stars/majorstars.shtml


-------------------------

WEIRD SCIENCE
Extreme slowing
Although the speed of an electromagnetic wave through matter is can be
up to 50% less than the speed through a vacuum, in 1999 scientists were
able to greatly reduce the speed through matter in special situations.

Danish physicists performed an experiment where they slowed light down
to only 38 miles per hour (about 57 km/hr) by sending a beam through a
molecule made of sodium atoms cooled to near absolute zero (- 273
degrees C or - 460 degrees F). They achieved this low temperature by
using lasers to slow down the atoms, through a special method used in
quantum mechanics called the Bose-Einstein condensate. (Explanation of
this goes away beyond the scope of this course).
http://www.school-for-champions.com/science/lightspeed.htm

.

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