Tag Archives: Faith

Polemics

Is Skeptic magazine keeping up with the progress of science?

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Not if the progress of science undermines the speculations about a naturalistic origin of life. In their latest issue, Skeptic magazine espouses the old, discredited Miller-Urey experiments from half a century ago. The old science is Darwin-friendly. But is that old science still current?

Consider this post from Evolution News.

Excerpt:

Stanley Miller had not in fact “simulated atmospheric conditions on the early Earth.” And this has been known for quite a long time. Origin of life theorist David Deamer states:

This optimistic picture began to change in the late 1970s, when it became increasingly clear that the early atmosphere was probably volcanic in origin and composition, composed largely of carbon dioxide and nitrogen rather than the mixture of reducing gases assumed by the Miller-Urey model. Carbon dioxide does not support the rich array of synthetic pathways leading to possible monomers . . . .

(D.W. Deamer, “The First Living Systems: a Bioenergetic Perspective,” Microbiology and Molecular Biology Reviews, Vol. 61: 239 (1997).

As I discuss here, there’s very good reason to understand why an atmosphere on Earth of volcanic origin would not contain methane or ammonia. A 2010 paper in Cold Spring Harbor Perspectives in Biology states that the chemical properties of the Earth’s mantle have not changed over time, and thus if volcanoes don’t produce appreciable amounts methane and ammonia today (which they don’t), then they also wouldn’t back then:

Geochemical evidence in Earth’s oldest igneous rocks indicates that the redox state of the Earth’s mantle has not changed over the past 3.8 Gyr (Delano 2001; Canil 2002).(Kevin Zahnle, Laura Schaefer, and Bruce Fegley, “Earth’s Earliest Atmospheres,” Cold Spring Harbor Perspectives in Biology (2010).)

The papers cited in the quote above confirm this point. For example, Canil’s 2002 paper in Earth and Planetary Science Letters found that vanadium redox states in peridotite-bearing mantle xenoliths and Archean cratons imply that Earth’s mantle was just as oxidized in the Archean as it is today. The paper concludes:

Abiotic synthesis of molecules and hydrocarbons that can lead to life in early Archean mantle-derived volcanic gases requires they contain significant H2 and CO, but such reduced components are not supported by results of this and many other studies, which imply a scenario of Archean mantle redox not unlike that of today. Life may have found its origins in other environments or by other mechanisms.

(Dante Canil, “Vanadian in peridotites, mantle redox and tectonic environments: Archean to present,” Earth and Planetary Science Letters, Vol. 195:75-90 (2002) (internal citation removed).)

The situation is summed by authorities Kasting and Catling as follows: “For the 4 billion years for which a geological record exists, no evidence for a pronounced change in mantle redox state exists.” (James F. Kasting and David Catling, “Evolution of a Habitable Planet,” Annual Review of Astronomy and Astrophysics, Vol. 41:429-463 (2003).)

Skeptic magazine cannot be skeptical on the origin of life. They have to affirm a naturalistic origin of life, because they assume that there was no intelligent cause of the origin of life, before looking at the evidence. They affirm that the universe is eternal, before looking at the evidence. They affirm that there is a multiverse to explain the fine-tuning, before looking at the evidence. They affirm that habitable planets are common, before looking at the evidence. They assume that a gradual string of pre-Cambrian fossils exists, before looking at the evidence. They believe in man-made catastrophic global warming alarmism, before looking at the evidence. Evidence is very, very bad for skeptics. Which is why they oppose the progress of science and have to go back fifty years to the speculations. They don’t like the progress of science. They believe what they want to believe. And that’s why they don’t want to debate anything, but instead refuse to hire people who disagree with them – or fire them if they are already hired.

It’s Skeptic magazine versus the scientists. Religion versus science. The pre-supposition of naturalism versus reality.

News

Scientists discover that tides affect a planet’s habitability

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Circumstellar Habitable Zone
Circumstellar Habitable Zone

Science Daily reports on a new factor that affects planetary habitability: tides. Specifically, tides can affect the surface temperature of a planet, which has to be within a certain range in order to support liquid water – a requirement for life of any conceivable kind.

Excerpt:

Tides can render the so-called “habitable zone” around low-mass stars uninhabitable. This is the main result of a recently published study by a team of astronomers led by René Heller of the Astrophysical Institute Potsdam.

[…]Until now, the two main drivers thought to determine a planet’s temperature were the distance to the central star and the composition of the planet’s atmosphere. By studying the tides caused by low-mass stars on their potential earth-like companions, Heller and his colleagues have concluded that tidal effects modify the traditional concept of the habitable zone.

Heller deduced this from three different effects. Firstly, tides can cause the axis of a planet`s rotation to become perpendicular to its orbit in just a few million years. In comparison, Earth’s axis of rotation is inclined by 23.5 degrees — an effect which causes our seasons. Owing to this effect, there would be no seasonal variation on such Earth-like planets in the habitable zone of low-mass stars. These planets would have huge temperature differences between their poles, which would be in perpetual deep freeze, and their hot equators which in the long run would evaporate any atmosphere. This temperature difference would cause extreme winds and storms.

The second effect of these tides would be to heat up the exoplanet, similar to the tidal heating of Io, a moon of Jupiter that shows global vulcanism.

Finally, tides can cause the rotational period of the planet (the planet’s “day”) to synchronize with the orbital period (the planet’s “year”). This situation is identical to the Earth-moon setup: the moon only shows Earth one face, the other side being known as “the dark side of the moon.” As a result one half of the exoplanet receives extreme radiation from the star while the other half freezes in eternal darkness.

The habitable zone around low-mass stars is therefore not very comfortable — it may even be uninhabitable.

Here is my previous post on the factors needed for a habitable planet. Now we just have one more. I actually find this article sort of odd, because my understanding of stars was that only high-mass stars could support life at all. This is because if the mass of the planet was too low, the habitable zone wouldbe very close to the star. Being too close to the star causes tidal locking, which means that the planet doesn’t spin on its axis at all, and the same side faces the star. This is a life killer.

This astrophysicist who teaches at the University of Wisconsin explains it better than me.

Excerpt:

Higher-mass stars tend to be larger and luminous than their lower-mass counterparts. Therefore, their habitable zones are situated further out. In addition, however, their HZs are much broader. As an illustration,

  • a 0.2 solar-mass star’s HZ extends from 0.1 to 0.2 AU
  • a 1.0 solar-mass star’s HZ extends from 1 to 2 AU
  • a 40 solar-mass star’s HZ extends from 350 to 600 AU

On these grounds, it would seem that high-mass starts are the best candidates for finding planets within a habitable zone. However, these stars emit most of their radiation in the far ultraviolet (FUV), which can be highly damaging to life, and also contributes to photodissociation and the loss of water. Furthermore, the lifetimes of these stars is so short (around 10 million years) that there is not enough time for life to begin.

Very low mass stars have the longest lifetimes of all, but their HZs are very close in and very narrow. Therefore, the chances of a planet being formed within the HZ are small. Additionally, even if a planet did form within the HZ, it would become tidally locked, so that the same hemisphere always faced the star. Even though liquid water might exist on such a planet, the climactic conditions would probably be too severe to permit life.

In between the high- and low-mass stars lie those like our own Sun, which make up about 15% percent of the stars in the galaxy. These have reasonably-broad HZs, do not suffer from FUV irradiation, and have lifetimes of the order of 10 billion years. Therefore, they are the best candidates for harbouring planets where life might be able to begin.

This guy is just someone I found through a web search. He has a support-the-unions-sticker on his web page, so he’s a liberal crackpot. But he makes my point, anyway, so that’s good enough for me.

Maybe the new discovery is talking about this, but I already knew about it because I watched The Privileged Planet DVD. Actually that whole video is online, and the clip that talks about the habitable zone and water is linked in this blog post I wrote before.

Atheism hates science

Theism loves science

Commentary

Why Christians should focus on cultural issues as well as evangelism

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Scott Klusendorf linked me this article on Facebook, in which he gives five reasons why Christians should not JUST focus on the gospel, but should instead be good at promoting goodness and opposing evil.

Excerpt:

First, it does not follow that because cultural reformers cannot make a culture blameless before God, we shouldn’t try to make it better for the weak and oppressed. I do not know of a single pro-life leader, for example, who argues that cultural reform can save souls eternally; only the gospel does that. The fact that cultural reform cannot get a man to heaven, however, does not mean that it cannot (in many cases through political means) save him from injustice here on earth. In short, pro-life advocates like me do not work for change in culture to save the world from spiritual death, but to save the most vulnerable members of the human family, the unborn, from physical death.

Second, the goal of cobelligerent cultural reform is not necessarily to change the hearts of individuals (whether saved or lost), but to restrain their evil acts. Martin Luther King, Jr., put it well: “It may be true that the law cannot make a man love me, but it can keep him from lynching me, and I think that’s pretty important.”3 The purpose of government, according to Scripture, is not to ensure salvation, but to promote justice (Rom. 13:1‑4). The primary purpose of the church, of course, is to preach the gospel of Christ, but if Christians, collectively, do not also challenge government to fulfill its duty to protect the weak and defenseless, who will?

Third, the notion that “there can be no real cultural impact apart from the transforming power of the gospel of Jesus Christ” sounds good, but it is simply incorrect. Consider the moral evil of slavery in America, which did not end because of mass conversions to Christ. It ended when believers and nonbelievers joined forces to stand against it—and paid for it with the lives of 360,000 Union soldiers. Was the abolition of slavery not a “real” cultural improvement? True, it did not make those who participated right with God, but it did take the physical whips off the backs of oppressed people. That is moral and cultural improvement by any reasonable standard.

Fourth, it is not spiritually unacceptable for Christians to mobilize with non-Christians for causes other than preaching the gospel. Prior to the Civil War, Protestant clergy worked with non-Christians and organized the Underground Railroad to free black slaves. Anyone who thinks that God’s people are wasting their time pursuing social justice may want to take a look at how important it is to God: Jeremiah 5:26‑28; 9:24; Isaiah 1:16‑17, 21‑23; 58:6‑7; 61:8; Psalm 94:1‑23; Proverbs 24:1‑12; Matthew 25:41‑46.

Fifth, why should anyone suppose that pro-life advocacy detracts from the discipline responsibilities of the local church as outlined in Matthew 28? Simply put, the answer to a lack of evangelical fervor for the Gospel is not to withdraw our political advocacy for the weak and vulnerable; it’s to encourage Christians to do a better job presenting the gospel. We don’t have to stop rescuing the innocent to do that.

This is why I try to have a balance of apologetics with other issues. And not just social policy, but fiscal policy and foreign policy. We need to have complete, comprehensive, coherent Christian worldviews. One obvious benefit of this is that we can connect Christianity with any topic when we are talking to others in the workplace, or anywhere that normal conversations occur. And if we study everything very well, people will link our intelligence to our faith. They’ll say “if you’ve put this much thought into economics, then you must have a well-thought-out faith, too”. Being well-rounded makes you more convincing, more influential on moral and cultural issues, and more effective at turning conversations to the gospel.