NASA's Spitzer space telescope has captured the light from what appear to be two planets
orbiting a sun. The above artist's conception illustrates a fiery hot star with its nearby
Other solar systems
in the globular cluster M4.3 (A globular
cluster is a very tight, spherical group-
ing of hundreds of thousands of stars.)
HE SOLAR system we The problem is that, according to the
live in is not the only one accretion modeI,4 grains of dust are
that exists. Over the last needed to form planets. But globular
several years, astronomers clusters, like M4, are made primarily
have discovered over 130 of hydrogen and helium, and are prac-
planets orbiting stars other tically a dust-free environment.5 For
than the sunY You might expect that this reason, most evolutionists had not
very little could be known about plan- expected to find any planets in globular
ets so far away, and you would be right. clusters.6 the astronomers say, was most likely
Neveltheless, astronomers have been Evolutionists generally believe that cleared out by a planet orbiting within
able to coax a few details about these globular clusters are very old, around the disk. There are other ideas that
worlds from the meagre data available, 12 billion years. According to their could explain the gap, but they do not
and it turns out that these extrasolar evolutionary scenario, there would not fit the data as wel!.?
planets, as they are called, are a serious have been much dust in the universe Secular astronomers estimate the
challenge to evolutionary ideas. when these clusters formed, which is age of the star CoKu Tau 4 to be 'only'
why, they believe, they are still so dust- one million years. The planet had to
A planet too 'old' for evolution
poor today. Thus, one might say that form after the star, according to evo-
According to the accepted evolu- this planet is too 'old' for evolutionary lutionary theories, so it should be even
tionary theory, planets form by accre- ideas. younger. The problem is that it would
tion. That is, bits of dust orbiting young take about jour million years for such
A planet too 'young'
stars collide and stick together to form a planet to form by accretion.8 If the
clumps of dust. These stick together, planet observations are accurate, then
or accrete, to form larger objects, until Another extrasolar planet has posed this planet is apparently too 'young'
eventually a planet is formed. But there just the opposite problem. Astronomers for evolutionary ideas-by the dating
is a problem with this idea. found a gap in the disk of dust and gas methods that evolutionists themselves
Scientists have discovered a planet around the star CoKu Tau 4. This gap, use. Astronomer Dan M. Watson said
that this planet 'really causes problems
for the standard model of planetary for-
Some evolutionary scientists have
recognized that the accretion model
does indeed have very serious prob-
lems, but they are not giving up on a
Extrasolar planet researcher Alan
p, Boss has suggested a different way
Main image: An artist's conception of the planet orbiting the
for planets to form, The gas in the disk
star CoKu Tau 4. This planet seems to be too 'young' for
of matter around a young star becomes
unstable, according to this theory, and
a clump contracts due to gravity, even- Above inset image: An artist's conception of the planet in the
tually forming a gas giant.l1 This way, globular cluster M4. This planet is apparently too 'old' for
planets condense directly from the gas, evolutionary ideas.
Left: Earth, our wobble can be studied to learn a little about
beautiful planet. the planet causing it. Or it can block the
Astronomers have star's light. More recently, astronomers took
what may be the first photograph of an
extrasolar planet, but there is still some
solar systems. uncertainty. See <www.eso.org/outreach/
However, none has press- rel/pr -2004/pr -23-04.h tm I>.
been shown to have 2. For an updated number, visit <planetquest.
a planet anything jpl.nasa.gov>.
like ours. 3. MacRo bert, A., The oldest, weirdest planet,
Sky & Telescope 106(4):18-19, 2003.
4. Scientisls often use the words 'model' and
5. Newton, R., New planet challenges
evolutionary models, TJ 17(3):9,2003.
6. Waller, W. and Hodge, P., Galaxies and
the Cosmic Frontier, Harvard University
Press, Cambridge, Massachusetts, USA,
7. Shiga, D., An 'impossibly' young planet?
l.asp>, 7 August 2004.
8. Mullen, L., Young planet challenges old
theories, <astrobio. net/news/modules. php?o
and can therefore form much more recently that the star Tau Ceti has a =993&mode=thread&order=0&thold=0> ,
7 August 2004.
quickly. Boss's scenario also does not disk of debris orbiting it. They inferred
9. Kerr, R.A., Youngest extrasolar planet
need dust grains, so it does not have the that there are 10 times as many small reported, Science 304:1423, 2004.
problems discussed above. objects such as comets and asteroids 10. Evolutionary astrophysicist Richard
But extrasolar planets do not con- orbiting this star as there are in our solar Durisen believes the problem may not be
that serious. He points out that the age of
form to Boss's theory, either. If this system.16 There mayor may not be any
the star is not known precisely, and thus it
theory were correct, planets should be planets orbiting Tau Ceti, but if there might be a little older. But even then, it
able to form either with or without dust were, they would be continually bom- would take a 'somewhat improved version'
of accretion to account for this planet. See
grains. But it turns out that extrasolar barded by impacts from these comets
planets are found mostly in environ- and asteroids.17 Such an environment 11. Boss, A.P., Formation of gas and ice giant
ments that are dust-rich. 12,13 would be very destructive to any sup- planets, Earth and Planetary Science Letters
This observation contradicts Boss's posed evolution of life. 202:513,2002.
12. Stated more precisely, planets are found
theory, which says dust has almost Astronomers already knew that hab-
preferentially in metal-rich environments.
nothing to do with planets. On the oth- itable planets were not easy to form.18 When astronomers use the word 'metal',
er hand, the observation that planets are But extrasolar planet discoveries are they mean any element heavier than
hydrogen and helium. It is these heavy
occasionally found in dust-poor places showing astronomers even more ways
elements that form the dust grains needed
is a problem for the accretion model, in which a world could be unsuitable by the accretion model.
which says that dust has everything to for life. 13. Schilling, G., Metals hint at how planets
do with the origin of planets. form, Sky & Telescope 106(3):23, 2003.
Distant solar systems 14. Chaisson, E. and McMillan, S., Astronomy:
support creation! A Beginner's Guide to the Universe, fourth
Is our solar system special? ed., Pearson Education, Upper Saddle River,
As more is learned about the uni- New Jersey, USA, p. 480, 2004.
The other solar systems that have 15. Di Cicco, D., Exoplanets and habitable
verse, more problems appear for evolu-
been discovered are not like ours, nor zones, Sky & Telescope 106(3):27, 2003.
tionary ideas. These discoveries about
would they be very hospitable to life, 16. Greaves, J.S., Wyatt, M.C., Holland, W.S.
extnisolar planets also suggest that our and Dent, W.R.E, The debris disc around 1:
In most cases, there are gas giants,
solar system, and especially planet Ceti: a massive analogue to the Kuiper Belt,
sometimes much larger than Jupiter, Monthly Notices of the Royal Astronomical
Earth within it, is a very special place in
in eccentric, or oblong orbits.'4 If a Society 351(3):L54, 2004.
the universe-evidence that fits beauti- 17. Tau Ceti system, Asteroid Alley-an
planet like Earth were in one of these
fully with Creation as God has revealed inhospitable neighbour, <www.pparc.ac.uk/
solar systems, these eccentric giants Nw/Ateroid_alley.asp>; 6 July 2004.
in the Bible. •
would destabilize its orbit. Their grav- 18. Taylor, S.R., Solar System Evolution: A
ity might even fling it out of the sys- New Perspective, second ed., Cambridge
University Press, Cambridge, UK, p. 442,
tem completely-not a good thing for 2001.
I. Astronomers usually cannot see these
living organisms that might inhabit that planets directly, but they can detect them
planet! Only about a third of the known indirectly in a number of ways. The key is
solar systems could have a planet like to measure the minute effects of the planet JUSTIN TAYLOR
on the star it orbits. For example, the is a student of mathematics and physics at a US
Earth in a stable orbit. IS gravitational pull of an orbiting planet will university. Justin plans to study astrophysics in
Astronomers have also discovered cause the star to wobble slightly, and this graduate school.