| http://www.youtube.com/watch?v=_Rh4NkGKTBk
Here's a video of a lecture by noted
creationist astrophysicist Dr. Jason Lisle. He's supported by leading
creationist website answersingenesis.org (also the producers of this
video) and is the author of Taking Back Astronomy: The Heavens
Declare Creation. The video runs
about 35 minutes. You can watch it all at once or try to watch it in
sync with my commentary, though the first approach may be better as I
am not certain that my replies are in exact chronological order.
His arguments sound
pretty convincing in this video, don't they? It sounds like legions
of astrophysicists have made some pretty big errors and then ignored
them in their quest to find further proof of evolution. It's
remarkable that Lisle's revolutionary view hasn't spread into the
broader academic community of astrophysicists, right? Wrong. Lisle
sounds good because most people don't have an intimate acquaintance
with physics (and of course they aren't to be blamed). He makes error
after error in this argument, and I intend to highlight these
mistakes and demonstrate that his arguments are based on poor
science, not “mistakes” by astronomers.
Early in the video,
Lisle says that the “incredible beauty and size of the Universe
demonstrate God's creative power.” Sure, the universe is, in
places, quite beautiful, and it is undoubtedly gigantic, but does
this demonstrate “God's creative power” or merely the
predictable, observable consequences of natural laws? For example,
pointing to a picture of the Butterfly Nebula, Lisle says that “God
made this star with the potential to become a planetary nebula.”
However, there are huge numbers of stars in our sky that have this
potential, including our own Sun. A star becomes a nebula because of
specific physical interactions as its core dies, and any star that is
about eight times the Sun's mass or less has this potential. Any gas
cloud that collapses into a star of that size also has this
potential. There is nothing special about the star that died and
became the Butterfly Nebula.
By saying that
astronomers know the Butterfly Nebula is less than six thousand years
old, Lisle indicates that he believes in the method by which
planetary nebula ages are determined—monitoring the expansion rate
of their gas shell. However, we can also see the remnants of the Vela
supernova, which has an expansion rate consistent with an age of ten
to twelve thousand years. Does his belief in gas shell expansion
rates extend only to gas shells less than six thousand years old?
What about the older shells, like the Vela supernova remnant, makes
them just seem older without them being that age? He needs to
have a very good scientific reason that those remnants are different,
but he provides none. If God created the Vela remnant six thousand
years ago, why does it behave like it exploded several thousand years
before that? Is God trying to trick us? The Vela remnant and the
Genesis account of creation are in conflict. They can't both be true.
Lisle repeatedly
refers to things that the Bible “got right” about astronomy,
mentioning that God “hangs the Earth upon nothing” and several
instances suggesting a spherical (or at least circular) Earth. Maybe
those things are right on astronomy (though some seem like a stretch
and Lisle admits this at one point), but he doesn't mention the
instances that are wrong about astronomy. Why would the Bible make
ten references
(http://www.biblegateway.com/quicksearch/?quicksearch=firmament&qs_version=9)
to the “firmament,” a solid sphere above the Earth in which the
stars are fixed? Towards the end of the video, Lisle claims that
“secular science” always needs to catch up to the Bible. When are
we going to catch up to the “firmament?” The idea of a firmament
is utterly in conflict with modern astronomy, which says that stars
are at greatly variant distances (confirmed by the parallax effect
and numerous other observations). However, a firmament is perfectly
consistent with a primitive understanding of astronomy, which holds
that the stars are at a fixed distance, stuck into the “celestial
sphere.” If you make astronomical observations with primitive or no
equipment, you would come to the same conclusion. However, modern
equipment is able to detect the parallax effect, which can accurately
measure the distances of stars within about five hundred lightyears
of ourselves (and there are other methods for more distant stars).
Lisle also neglects to discuss Joshua 10:12-14, in which God makes
the Sun and moon stand still in the sky so the Israelites can win a
battle against the Amorites without giving them the cover of night to
rest and regroup. What's wrong with this? The Bible says that the Sun
“stood still” and the moon “stopped.” As modern astronomers
know, the Sun and moon do not revolve around the Earth once per day.
Their motion through the sky is due to Earth's rotation. The Sun and
moon do have some movement through space, but if they stopped moving
in this way, the result would not be the lengthening of the day. The
Earth would still rotate, and the Sun would still set. The only way
to make the Sun “stand still” is not to stop the Sun, but to stop
the Earth's rotation. The Bible again reflects the primitive
understanding of astronomy—geocentrism. It's wrong.
Lisle also asserts
that the Second Law of Thermodynamics was still in play prior to the
fall of man, but that it was balanced by “God's restoring power.”
This reflects a few mistakes. One—the Second Law of Thermodynamics
is violated if entropy decreases without any work being done. If God
was “restoring” the universe to order, He would have to either
physically work—and thus increase entropy because there would be
wasted energy unless such factors as air resistance and friction were
eliminated (which would require still more physical work or a miracle
to eliminate them)—or work through miracles, which would decrease
entropy without work and thus violate the Second Law of
Thermodynamics. If God was restoring the Universe, the Second Law of
Thermodynamics wasn't in effect. Secondly, it wouldn't even
necessarily apply, as Adam and Eve would be creating a tiny amount of
entropy (body heat, digestion, etc) and Eden as a whole would also be
making a relatively small amount of entropy when compared with the
modern world. They were fine for an extremely long amount of time
with entropy in effect. Would they even need to eat? After all, in a
perfect world there would be no need for hunger or body heat. The
Second Law of Thermodynamics may not have even been necessary in such
a situation.
Dr. Lisle suggests
that the heat radiating from Jupiter and Neptune (and Saturn, but he
doesn't point that out) is not consistent with a very old Solar
System because they would have cooled off by now if they started off
hot, but that they are consistent with a young solar system, which
would allow them to still have “leftover” heat. This explanation
makes sense—if you don't believe in the Ideal Gas Law (and its
relative, the Van der Waals equation). The Ideal Gas Law says that if
you have an amount of gas, the pressure of the gas divided by its
volume will always equal the temperature (with a few mathematical
constants thrown in to keep the units of measurement in proportion).
This means that if you increase the pressure of a gas or decrease its
volume (or both), its temperature will increase. At the core of a
body like Jupiter, there is intense pressure due to the weight of the
thousands of miles of gases above. These gases are also compressed
into a tiny area. If their temperature decreases due to cooling,
pressure will drop as the molecules exert less force on their
surroundings (that's all pressure is, force on surroundings). Since
they exert less force on the gases above them, these gases will
compress the core because their weight is not being balanced by
upward force in the form of pressure. This compression is a decrease
in volume, which causes an increase in pressure as the gases are
packed into a smaller area. More pressure in less volume equals an
increase in temperature. Thus, Jupiter's core remains hot. This is
known as the Kelvin-Helmholtz mechanism. It's been understood for
over a century.
Dr. Lisle says that
the Earth's magnetic field is declining, therefore the Earth must be
very young. However, we can observe the behavior of the Earth's
magnetic field well back into prehistory by looking at the
positioning of ferromagnetic particles frozen in lava flows. They
naturally align with the Earth's magnetic field (just like a compass
needle), so they indicate its direction and strength at the time the
lava flow solidified. The present decline is well withing the
historical range. Also, we have observed that the field has reversed
itself several times (so the “north” end of a compass needle
would point south). These reversals tend to happen during periods of
low field strength, and we could be overdue for a field reversal. The
last one was 780,000 years ago, and they generally happen more
frequently than that.
Dr. Lisle claims
that dynamo theory—the current theory for the origin of a planet's
magnetic field—is not true. Why? What evidence does he have against
this? Convective flows of metals in the Earth's core are consistent
with both the composition of the core and our calculations, so why is
this not true? Perhaps his sole reason is that dynamo theory offers a
valid explanation for the origins (and possibly behavior) of the
magnetic field that can occur on a scale of billions—not
thousands—of years without running down.
Dr. Lisle says that
the Oort Cloud isn't real. Yes, we haven't observed it, but this is
because it is composed of small, cold bodies at extreme distances
(thousands of times the distance to Pluto). It's simply beyond our
present observational capabilities. This doesn't mean it doesn't
exist. The existence of the Oort Cloud is also consistent with solar
nebula theory, which adequately explains so much of our solar system.
Dr. Lisle states
that the Moon is receding so rapidly that it cannot have been around
for more than one to two billion years. However, modern calculations
suggest that the (1960s era) calculations behind this were flawed,
and that the moon would not have flown away long ago if it is indeed
4.5 billion years old. (See www.talkorigins.org/faqs/moonrec.html
for a much more detailed explanation of the calculations involved).
Dr. Lisle states
that a spiral galaxy such as our own would become “wound up” due
to the rapid rotation of the center relative to the outer arms. He
dismisses other hypotheses such as spiral density waves, but why? He
simply dismisses the idea out of hand without giving any explanation
why the spiral density wave idea (the idea that the stars move in
elliptical orbits around the galactic center and that these orbits
are related in such a way that there are areas of dense star
concentration where the ellipses are close together and areas of
sparse star concentration where the ellipses are far apart, creating
an illusion of spiral arms) is incorrect. (See
http://en.wikipedia.org/wiki/Image:Spiral_galaxy_arms_diagram.svg
for an example of how ellipses could combine to create a spiral
illusion).
Dr. Lisle suggests
that “evolutionists” believe that “the universe was created
naturally, by itself.” This is a very biased way to word this,
because if the universe “was created” it must have had a Creator
and could not have “created itself.” This reflects a primitive
understanding of the present conception of the origins of the
universe, which suggest it arose or simply expanded into its
present form. To say it “was created” is wordplay. Even his usage
of the word “evolutionists” is simplistic. Believing that the
“Big Bang” explains observed galactic redshift and that natural
forces account for the present configuration of the stars and
galaxies has no relationship to biological evolution. “Evolutionists”
is a term that Lisle uses to create a dichotomy—evolutionists
versus creationists, us versus them. It strengthens in-group
solidarity and facilitates stereotyping of a broad group of people.
He's playing to his base, not using accurate wording.
Some of Lisle's
biggest errors come in his discussion of planetary rotation.
Discussing the idea that planetary tilt is caused by impacts, he
states that Saturn's tilt is very large. While Saturn is rather
tilted, he is apparently referring to Uranus, the famously sideways
planet with a much larger tilt. He also states that Saturn is “too
large” to be tilted by impact. Whether he's referring to Saturn or
Uranus, his statement is glaringly arbitrary. Any rotating body could
be tilted by an impact of sufficient force. To say that a planet is
“too large” to be tilted is to suggest that planet-sized objects
behave according to a different set of physical laws which allow
their rotational tilt to be absolute, regardless of outside forces.
Lisle then states that there are three planets that rotate backwards,
and that this is inconsistent with solar nebula theory. Let's count
the planets that rotate backwards. Venus is one. I'm in a friendly
mood, and I'll give him sideways Uranus as a second. He's still one
planet short, and there are only eight planets (possibly nine at the
time he gave the lecture). This man has a PhD in astrophysics, and he
doesn't know that only one planet rotates backwards? There are a few
moons that orbit backwards, but it's perfectly reasonable that they
were captured by their much larger planets and thus happen to have a
backwards orbit. Impacts could explain backwards planetary rotation,
and calculations have demonstrated that the tidal effects of the
Sun's gravity on the massive Venusian atmosphere could cause the
planet to rotate as it now does—very slowly backwards. Lisle also
states that the Sun's rotation is “too slow” to account for the
angular momentum of the planetary nebula. However, current hypotheses
suggest that dust in the nebula could have slowed rotation. Why does
he dismiss this theory without providing evidence against it or even
mentioning it?
Dr. Lisle then
explains that the Earth must have been created because the only
planets we have observed outside our Solar System (extrasolar
planets) are very large and close to the stars they orbit. He assumes
that the lack of planets similar to ours indicates that we are
unique. However, detecting extrasolar planets is extremely difficult
because of the huge distances and small sizes involved. The simplest
way to spot an extrasolar planet is to look for a star that wobbles
slightly due to the gravity of a nearby planet. Another method is to
look for stars that dim as a planet passes between our viewpoint and
the star, blocking some of its light. These and other methods are all
very good at finding planets that are very large and very close to
the stars they orbit, but they are bad at finding small planets. The
wobble method requires a detectable wobble, which requires a large
planet close by for the gravitational effects to be large enough. The
method of watching for a star to dim as a planet passes close by
requires that the planet be in an orbit that crosses between us and
its star—think of how rare solar transits by our small Mercury and
Venus are—and that the planet be large enough to cause a detectable
reduction in light. Look up pictures of a transit of Mercury and
you'll get an idea why it's so hard to detect tiny planets with the
transit method. Tiny planets can't block much light at all. At
present, we simply don't have the technology to detect the much
smaller signs of tiny planets like our own.
Lisle also talks
about how planets can't form and then move closer to their star
because there's nothing to stop them from falling into their star and
being incinerated. Actually, there is something that can stop a
planet from falling in, and he talked about it earlier—conservation
of angular momentum. If an object of constant mass's orbital radius
shrinks, its velocity will increase. The closer you get a planet to
its star, the faster it will orbit, and this can quite easily stop
its inward motion and keep it in orbit. Satellites that are at the
end of their service are often pushed upward into very high orbits
around Earth to keep the low orbits clear. Why not just burn them up
in the atmosphere? It takes a lot of energy to overcome angular
momentum to the point that the satellite can get low into Earth's
atmosphere and begin experiencing large air resistance, which would
slow it down enough to pull it the rest of the way in. Pushing it out
is much easier (and it doesn't run the risk of crashing a burning
satellite remnant into a populated area).
Lisle shows a quote
from Isaac Newton about how the Earth must have been created because
it lies within a “zone of habitability” at which we get the
perfect amount of energy from the Sun. However, the zone of
habitability is actually a large swath of space between Venus and
Mars. Variations in the Earth's distance to the Sun due to its
elliptical orbit keep it well within this zone, and these variations
account for only a small amount of seasonal temperature variation.
The Earth's tilt is much more important. The zone of habitability may
actually be quite a bit larger than we think, as a planet with an
atmosphere that regulates its temperature well could be more distant.
There is also the example of the possibility of life on Europa.
Europa lies well outside the zone of habitability (it is a ball of
ice orbiting Jupiter), but some scientists suspect that it could
harbor some life in an ocean beneath its ice. If it has sufficient
geothermal activity, this ocean could reach life-supporting
temperatures (which are actually quite a large range—I've seen
bacteria flourishing in extremely hot, sulfurous water draining from
geothermal features in Yellowstone National Park). Lisle's argument
that Venus is too hot and Mars is too cold also has no bearing on the
possibility of life on extrasolar planets like ours within the
narrower interpretations of the zone of habitability.
Lisle shows a
picture of Mars and comments on how lifeless it is. However, there is
extensive geologic evidence on the Martian surface of hydrologic
activity in the distant past (most scientists say about 3 billion
years ago). There is debate among scientists as to whether this
lasted for a brief, cataclysmic period or a longer era (and hopefully
this will be resolved by emerging discoveries in the next few
decades), but if it was a longer era, life could have existed on
Mars.
Lisle calls
extraterrestrial life “a secular replacement for God.” The
popular conception of extraterrestrial life is little green men in
flying saucers with incredible, advanced technologies and the ability
to teach us to live in peace and prosperity. Sure, that sounds like
God, but that's just the popular idea of what extraterrestrial
life is like. While many scientists believe that extraterrestrial
life is quite possible, they don't necessarily believe that it's as
advanced or more advanced than humanity. It could even be extremely
primitive, like bacteria (Satellites going to other planets are very
carefully cleaned and kept away from some planets and moons to avoid
accidentally introducing Earth bacteria that could utterly destroy
fragile life forms). There's no reason to “worship”
extraterrestrial life, especially since we apparently haven't seen it
yet. Even if they were incredibly advanced and “godlike,” they
wouldn't be gods and they wouldn't be worthy of worship. They'd just
be advanced. The early inhabitants of South and Central America
thought that the technologically advanced Spanish were gods, but they
weren't. They were leaps and bounds ahead in many technological
fields, but that did not merit them a god-worthy reception.
Lisle claims that
the cosmic microwave background—the so-called “echo” of the
“Big Bang”—is almost entirely uniform. He's right on
that—almost. However, he neglects to mention that one of the
most important discoveries of the last fifteen years in astronomy is
that there are slight variations in the background, and that
these variations are quite consistent with the distribution of matter
in the universe, suggesting that the “Big Bang” happened as we
thought it did. The redshift of the cosmic microwave background is
consistent with our expectations, and it is almost impossible for
this radiation to have originated from any source other than the Big
Bang because it is visible in all directions and its spectrum could
not be emitted by normal matter (which would show absorption lines as
chemicals absorb photons on frequencies there electrons “like”).
For more information on the cosmic microwave background, check out
http://www.astro.ubc.ca/people/scott/faq_basic.html
or
http://www.astro.ubc.ca/people/scott/faq_email.html#CMB_anisotropy.
Lisle's
understanding of astronomy is remarkably poor. This man has a PhD in
astrophysics, but I can see through his arguments after a single
semester of astronomy class. His desire to see evidence for
creationism in astronomy has led him to these embarrassingly
primitive arguments.
Though Lisle only
briefly mentions it, a common critique of creationism is the
“starlight problem”—how can we see galaxies that are billions
of light years away (i.e. the light would take billions of years to
get here because a light year is the distance that light travels in
one year) if the universe is only six thousand years old? A common
creationist response is that the speed of light was once much faster
than it now is, which would allow this distant light to reach us in
time. They often cite modern examples of the speed of light being
slowed in a laboratory, which supposedly demonstrates that the speed
of light is variable. However, the conditions under which light can
be slowed are extremely fragile (or require a solid medium like a
lens) and wouldn't occur for such a long period over the entire
expanse of space. Also, changing the speed of light would cause the
amount of energy released as the Sun (and other stars) converts
matter into energy to dramatically increase, frying the Earth and
having very obvious consequences around the universe (this is a
result of Einstein's famous equation E=mc²,
which means that the energy (E) released when converting matter to
energy is equal to the mass converted (m) times the speed of light
(c) squared. An increase in c would cause a gargantuan increase in
the amount of energy released). For more detailed information on
this, check out http://www.talkorigins.org/faqs/c-decay.html
or http://wiki.cotch.net/index.php/C-decay.
I hope my
explanations have been enlightening.
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