The Earth and other planets
Published: 19 September 2020 (GMT+10)
CMI supporter John T. asked us about the structure of Earth’s atmosphere and whether other planetary atmospheres could possibly have evolved.
Hello - I am on your subscribers list …
I’ve been born again since 1974 and an avid young earth creationist since 1978.
Of all the 1000’s of articles I’ve read in over four decades I cannot recall having read any about the following:
the Earth’s at least seven atmospheres. From the highest, exosphere, to the stratosphere, and all in between – ionosphere, troposphere, ozone layer etc.
The question is: do other planets in our solar system have atmospheres anything like Earth’s? Surely, these ‘spheres’ – which we know are there for a specific purpose – are overwhelming evidence for creation, for how could such protective layers ever evolve?
Perhaps one or more of the team could produce an article about this, please?
Philip Bell replies:
It is always good to read of someone’s testimony and faithful stand upon biblical creation, even if briefly—we appreciate you sharing that.
Thank you for your message and query regarding the various atmospheric levels that have been identified as we rise in altitude above the Earth. Just recently, my family and I watched a somewhat fanciful but entertaining movie called The Aeronauts (inspired, said the film-makers, by historical events). It depicts two people going up in a gas balloon in 1862, one of them the pioneering meteorologist James Glaisher who indeed discovered, from the instrumentation he had on board, that there were atmospheric levels. On a global scale those levels can be conceived as ‘shells’ or spheres—invisible of course to the naked eye.
You mention “at least seven atmospheres” but I’m not sure where your number seven comes from. From what you’ve stated, you are obviously aware that (moving progressively outwards from Earth’s land/sea surface) atmospheric scientists talk of the troposphere (which constitutes the majority of Earth’s atmosphere by mass), the stratosphere (which is within reach of very high weather balloons, then the mesosphere and thermosphere (the latter two levels being in excess of 50–65 km (31–40 mi) in altitude, depending on latitude and the time of year)—see diagram. The exosphere (greater than ca. 600 km/373 mi high) is basically where the very rarefied outer atmosphere merges into space itself, so it’s arguable that this doesn’t really count as an atmospheric layer as such—this is getting to the altitude at which satellites and the International Space Station orbit the Earth. My guess is, that to arrive at “seven”, you have taken the first four levels (excluding the exosphere) and have added the Tropopause, Stratopause and Mesopause. Regarding the latter three ‘pauses’, note that these are invisible boundaries between layers, not layers themselves; that is, they are the altitudes at which scientific instruments detect significant changes, chiefly in relation to temperature. The altitude of the three ‘pauses’ changes between summer and winter (all three are much higher in winter). But you may not have had these ‘pauses’ in mind.
Ionosphere and magnetosphere
Instead, perhaps you were including such things as the ionosphere which you mentioned (which begins at approx. 80 km altitude, but is within the thermosphere) and the magnetosphere.
The ionosphere extends up to about 600 km (373 mi) so partly straddles the exosphere. As the name suggests, it is a region where atoms and molecules have been ionised (due to solar radiation), creating free electrons. These reflect and absorb radio waves (permitting shortwave radio for example; see God’s provision for missionary radio) and are also important in the context of satellite communication and GPS navigation (using the Global Positioning System).
While I suspect you did not have the magnetosphere in mind, some people might be forgiven for confusing it with the atmosphere. But in spite of the similarity in nomenclature, it is not spherical at all, rather, it is the moniker for the invisible magnetic field lines associated with the Earth’s magnetic field. These extend vast distances into space and shield Earth from the solar wind, highly energetic charged particles from the sun’s atmosphere which stream out into the Solar System in all directions. On the side of our planet facing the full onslaught of the solar wind (i.e. the daytime side), the magnetosphere is compressed, but still it extends tens of thousands of kilometres from Earth. On the leeward side of Earth (its night side), the magnetosphere stretches out to more than 6 million km (3.7 million mi)!
Famously, interactions of the magnetosphere with the solar wind lead to the dazzling polar light displays called aurorae. In June the news media reported that a craft launched by the European Space Agency (ESA), the ExoMars Trace Gas Orbiter, had seen “an odd greenish glow” in the atmosphere of Mars.1 (You asked about other planetary atmospheres and I’ll say more about that subject later on.) This rarely-seen, eerie atmospheric phenomenon is akin to Earth’s aurora borealis (northern lights) and aurora australis (southern lights) and the green glow is believed to signal the presence of oxygen in the Martian atmosphere—there is a superb picture of it on the ESA’s website report.5
Purpose of Earth’s atmosphere
Coming back to your question of atmospheric levels, it is an interesting subject but not one which generally excites big differences of opinion between creation apologists and those who advocate a secular view of origins. Nevertheless, certain aspects of the atmosphere have been written about on creation.com over the years and you could find those articles by using such search terms as ‘stratosphere’, ‘troposphere’ and so on. As just one example, in recent years biblical creationist and physicist, Jake Hebert (whose PhD looked at the possible connection between fair-weather atmospheric electricity and climate) has written a number of articles on meteorological subjects, such as this in-depth article, Two possible mechanisms linking cosmic rays to weather and climate.
You mentioned a “specific purpose” for these atmospheric ‘spheres’. Without doubt there is a purpose for the atmosphere as a whole: in short, without it, there would be no possibility of life on Earth—a brief discussion can be found here: Created to be inhabited: Amazing design features in planet Earth. And, for a long time, scientists who disregard Scripture have tried to explain how Earth’s present atmosphere arose over the millions of years of deep time, starting with an allegedly more primitive atmosphere. There is no need here to rehearse the many reasons why there is clearly overwhelming evidence for our atmosphere (primarily thinking of the troposphere) having been designed for life, as I’m sure you are aware of much of this already. You mentioned the ozone layer. The stratosphere contains most of the ozone, which people are more aware of than used to be the case, due to concerns over ozone holes brought about by pollution of the atmosphere with man-made substances like CFCs (chlorofluorocarbons). Clearly, the ozone has a vital protective role by virtue of its absorption of dangerous UV radiation.
The purposes of the mesosphere and thermosphere are perhaps not immediately obvious but both are important. Most of the asteroids and meteors which are on a collision course with Earth burn up in the mesosphere before they can cause any damage, so its protective effect is very important. Also, where the air is much thinner in the mesophere’s upper reaches, the extreme cold (down to -90°C; -130°F) means that water vapour freezes as tenuous clouds of minute ice crystals. These are called noctilucent clouds (literally ‘night-shining’ clouds) that can be seen on summer’s evenings when the sky is fairly clear and the sun has dipped below the horizon—they are found above an altitude of 76 km (47 mi).2
What about the thermosphere’s purpose? It is so-called because its absorption of solar radiation is maximal, making it the hottest atmospheric layer—temperatures range from 200°C (392°F) to well over 2,000°C (ca. 3,700°F).3 Since the aurorae mostly occur in the thermosphere, some people might argue that it has a purpose in exhibiting great beauty to those able to observe these mesmerising light displays.
Possibly, the existence of verifiable atmospheric layers may partly be explained as a natural, physical consequence of God having created Earth at its particular size, with its particular magnetic field strength, its specific composition of gases, and its particular water component (thus forming water vapour clouds as opposed to clouds of other substances). If that is true, one might concede that not every aspect of our atmosphere’s ‘structure’ would necessarily strongly point towards design from the perspective of the secularist. But for those with eyes to see the Creator’s handiwork the design of the atmosphere is a no-brainer and there is no credible evidence that the particulars I’ve just mentioned (plus other necessary factors) could gradually have arisen (‘evolved’) on some primordial Earth.
So, regardless of exactly which “seven atmospheres” (or more) you had in mind, clearly there is no doubt that Earth’s atmosphere is amazing, nor is there any doubt as to the vital role that it plays in facilitating our existence, as well as that of the millions of species of living organisms on Planet Earth.
Other planetary atmospheres
And, as you enquired, this naturally makes us wonder whether other Solar System planets—and I would add, extrasolar planets (those reported round other stars)—“have atmospheres anything like Earth’s?” Other planets in our Solar System definitely do have atmospheres—and some have been studied very closely—but none has a comparable atmosphere to Earth’s.4 Take Mars and Venus for instance, Earth’s nearest planetary neighbours.
Venus has a toxic atmosphere of mostly carbon dioxide (plus nitrogen and traces of other gases), clouds of sulphuric acid, absolutely crushing pressures and a high average temperature of 464°C (867°F). That temperature is way above that required to melt metals like tin, zinc and lead—melting points of 232°C (449°F), 419°C (788°F), and 328°C (621°F) respectively!
Mars has an atmosphere that is also mostly CO2 (>95%) but much more rarefied than Earth’s atmosphere (with a surface air pressure <1% of Earth’s) and a frigid average temperature of -65°C (-85°F). No life-support exists in those places, neither on any other planet or moon in our Solar System—not even close! And the same goes for planets around other stars.
You say, “surely [they] are overwhelming evidence for creation”. I don’t disagree. In a sense, Christians can see that everything that exists in the universe points to creation and the Creator. I’m not sure that such a strong apologetic for biblical creation (as against deep time evolution) can be made from a consideration of all these atmospheric phenomena—but maybe it remains for people to research and demonstrate this in an even more compelling way than has been done up until now.
You also mention that you “cannot recall having read any[thing] about” the structure of the atmosphere. I suspect that the reason why creation apologists have probably spent less time researching and writing about these matters than other subjects is partly because the existence of these atmospheric levels is not controversial. Whether people are biblical creationists or are evolutionists, they are unlikely to disagree on such matters as the structure of the Earth’s atmosphere. However, concerning the atmosphere’s origin there is definitely disagreement: opposing worldviews lead to huge differences in one’s conclusions. Biblical creationists believe that the Creator designed Earth’s atmosphere and set it in place miraculously. The secular thinker will appeal to some sort of drawn out naturalistic process to arrive at our present atmosphere, but the irony is that such ideas are purely hypothetical and frequently require naturalistic ‘miracles’ to boot.
I trust this has been of some interest and help.6
References and notes
- European Space Agency, ExoMars spots unique green glow at the Red Planet, esa.int, 15 June 2020; accessed 2 July 2020. Return to text.
- The more familiar wispy, cirrus clouds (and related cirrostratus and cirrocumulus clouds) are found between 5–14 km (3.1–8.5 miles) high, which is within the troposphere and stratosphere. Return to text.
- NASA’s website puts this figure as high as 4,500°F; spaceplace.nasa.gov/thermosphere/en; accessed 27 July 2020. Return to text.
- Anon, The atmospheres of the Solar System, compoundchem.com, 25 July 2014. Return to text.
- www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Exploration/ExoMars/ExoMars_spots_unique_green_glow_at_the_Red_Planet Return to text.
- You may also wish to listen to these podcasts on the subject: Our young solar system, and Planets are young 2. Return to text.