Around the web 1/5/2013

EARTH IS JUST ONE PLANET OUT OF 100 BILLION — From Astrobiology.com: 100 Billion Planets May Populate the Galaxy. Not only could there be 1011 planets in the Milky Way galaxy alone, there are an estimated 1021 stars in the universe. This seems to make Earth, and the humans who inhabit it, seem rather insignificant. But consider this quote from John Piper:

Sometimes people stumble over this vastness in relation to the apparent insignificance of man. It does seem to make us infinitesimally small. But the meaning of this magnitude is not mainly about us. It’s about God… The reason for ‘wasting’ so much space on a universe to house a speck of humanity is to make a point about our maker, not us.” –John Piper, Seeing and Savoring Jesus Christ.

YOU ARE JUST ONE DOT OUT OF 341,817,095 — An online map showing over 340 million dots, one for each person in the 2010 United States and 2011 Canadian censuses.

Census_dots

Zoom in and individual dots can be resolved. My dot is somewhere in the middle of here:

Census_dots_zoomed

Does being just one dot out of 340,000,000 (or one dot out of roughly 7,000,000,000 on Earth today) make the individual dots insignificant? Not at all. The same God who created the universe with its 1021 stars, or the galaxy with its 100 billion planets, has this to say about you as an individual:

For God so loved the world,that he gave his only Son, that whoever believes in him should not perish but have eternal life.” — John 3:16 ESV

DANGEROUS SCIENCE?7 scientists killed by their experiments — Marie Curie, and six others.

COLDER THAN COLD? — According to one report (Science gets colder than absolute zero), temperatures colder than absolute zero are possible.

Absolute zero is often thought to be the coldest temperature possible. But now researchers show they can achieve even lower temperatures for a strange realm of “negative temperatures.”

Oddly, another way to look at these negative temperatures is to consider them hotter than infinity, researchers added.

This unusual advance could lead to new engines that could technically be more than 100 percent efficient, and shed light on mysteries such as dark energy, the mysterious substance that is apparently pulling our universe apart.

——————————————

Temperature is linked with pressure — the hotter something is, the more it expands outward, and the colder something is, the more it contracts inward. To make sure this gas had a negative temperature, the researchers had to give it a negative pressure as well, tinkering with the interactions between atoms until they attracted each other more than they repelled each other.

Or perhaps this is in the same category as last year’s report of particles going faster than the speed of light. Interesting, but not true.

Grace and Peace

Around the web 12/1/2012

NUKE THE MOON!!!! — U.S. had plans to nuke the moon — The U.S. Government really wanted to explode a nuclear weapon on the moon in the late 1950s, sort of as a macho “We’re better than the Soviets” thing. One of the researchers on this project was a graduate student named Carl Sagan.

BIG NEWS FROM MARS? — Has Curiosity made a Historic Discovery? — Complex organic chemicals? Fossils? Little green men? Elvis? For now, they seem to be keeping the lid down tight on whatever their discovery is.

I have a young-Earth creationist friend who is convinced that there is no life anywhere in the universe but here on Earth. Despite the fact that the Bible doesn’t say anything about the topic. Not all YECs are worried, however.

LOOKING FOR GOOD SEX?Searching for God, settling for sex — An editorial on CNN.com.

In the absence of genuine sexual intimacy (best defined as “in-to-me-see”), we settle for sexual intensity: erotica, pornography, an office romance, an extramarital affair or whatever strokes the ego and provides the sexual high we crave.”

Someday I might write a “50 good reasons to believe Christianity is true” post, and one of the reasons will be that Christianity gets sex right.

PAT ROBERTSON GETS ONE RIGHT — Pat Robertson Challenges Creationism

“I know that people will probably try to lynch me when I say this.”

“You go back in time, you’ve got radiocarbon dating. You got all these things, and you’ve got the carcasses of dinosaurs frozen in time out in the Dakotas. They’re out there. So, there was a time when these giant reptiles were on the Earth, and it was before the time of the Bible. So, don’t try and cover it up and make like everything was 6,000 years. That’s not the Bible.”

BETTER THAN THE GEOCHRISTIAN — My “Around the Web” posts are a poor imitation of Saturday Ramblings, posted weekly on Internet Monk. In this week’s Saturday Ramblings: Vampires in Serbia, “What Would Jesus Shoot?”, Charisma magazine’s rather goofy article on sex (OK, Christians doesn’t always get sex right), and Jimi Hendrix.

Grace and Peace

Jesus is for geologists (and other scientists)

I’ve always known that Jesus is for geologists, as well as for biologists, chemists, physicists, archeologists, astronomers, and all other sorts of scientists.

There are, of course, many Christians who are scientists, and many scientists who are Christians. As a graduate student in geology, I found rich fellowship with a half dozen Christian geologists-in-training, and there was a Christian on the faculty of the department as well.

Davis Young, a Christian geology professor (retired), and author of The Bible, Rocks and Time, Christianity and the Age of the Earth, and Mind over Magma: the Story of Igneous Petrology, has written what he considers to be his most important book: Good News for Science: Why Scientific Minds Need God.

The summary on Barnes & Noble reads:

Bridging the fields of natural science and religion, Good News for Science: Why Scientific Minds Need God invites members of the professional scientific community, graduate, undergraduate, and high school science students, science teachers, and members of the general public who are interested in the natural sciences to embrace the Christian faith personally. Employing the theme of good news, this book challenges readers to ponder the question of life after death as a gateway to the overall claim that Christianity, at its best and most consistent, bears good news for both science and the scientist. On the one hand, Christianity, far from being antithetical to science, supplies the rational foundation that makes the scientific enterprise possible. On the other hand, the central message of Christianity brings a firm hope to scientists as individual persons in meeting their deepest needs and desires for genuine significance, purpose, goodness, forgiveness, justice, and relationship with the Creator. In presenting his case, the author eschews pseudo-science and treats with great respect the discoveries of contemporary mainstream natural science, including an ancient universe and Earth, biological evolution, and the standard model of cosmology. The text adopts an informal, personal, conversational style. Good News for Science will be of interest not only to the general scientific community but also to Christians who are seeking a resource to use in presenting Christian faith to scientifically knowledgeable individuals.

As the review says, this would be a great book for

  • Professional scientists
  • Students of science, at either the undergraduate or graduate levels
  • High school teachers and students
  • Members of the general public.

Buy this book at Barnes & Noble or Amazon.

Grace and Peace

Arsenic in DNA – maybe

Figure 1 -- Phosphorus and arsenic on the periodic table.

News of surprising biochemistry: Thriving on Arsenic (NASA Astrobiology Magazine)

NASA microbiologist Felisa Wolfe-Simon has discovered bacteria that apparently can use arsenic in its DNA in place of phosphorus. Most biochemistry can be done with six elements: carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS). Smaller amounts of a variety of other elements are also necessary to varying degrees depending on the organism, such as sodium, calcium, iron, and magnesium. Arsenic is similar enough to phosphorus (same column in the periodic table, Figure 1) that within these bacteria it may be able to play the same role.

From the Astrobiology Magazine article:

The recent discovery by Felisa Wolfe-Simon of an organism that can utilize arsenic in place of phosphorus, however, has demonstrated that life is still capable of surprising us in fundamental ways. The results of her research were published December 2 on Science Express and subsequently in the journal Science.

The organism in question is a bacterium, GFAJ-1, cultured by Wolfe-Simon from sediments she and her colleagues collected along the shore of Mono Lake, California. Mono Lake is hypersaline and highly alkaline. It also has one of the highest natural concentrations of arsenic in the world.

On the tree of life, according to the results of 16S rRNA sequencing, the rod-shaped GFAJ-1 nestles in among other salt-loving bacteria in the genus Halomonas. Many of these bacteria are known to be able to tolerate high levels of arsenic.

But Wolfe-Simon found that GFAJ-1 can go a step further. When starved of phosphorus, it can instead incorporate arsenic into its DNA, and continue growing as though nothing remarkable had happened.

“So far we’ve showed that it can do it in DNA, but it looks like it can do it in a whole lot of other biomolecules” as well, says Wolfe-Simon, a NASA research fellow in residence at the USGS in Menlo Park, California.

The article describes the methods used to purify the DNA, to ensure that the arsenic was truly incorporated into the structure of the DNA rather that being associated with other molecules. Not all, however, are convinced.

But Steven Benner, a distinguished fellow at the Foundation for Applied Molecular Evolution in Gainesville, FL, remains skeptical. If you “replace all the phosphates by arsenates,” in the backbone of DNA, he says, “every bond in that chain is going to hydrolyze [react with water and fall apart] with a half-life on the order of minutes, say 10 minutes.” So “if there is an arsenate equivalent of DNA in that bug, it has to be seriously stabilized” by some as-yet-unknown mechanism.

Benner suggests that perhaps the trace contaminants in the growth medium Wolf-Simon uses in her lab cultures are sufficient to supply the phosphorus needed for the cells’ DNA. He thinks it’s more likely that arsenic is being used elsewhere in the cells, in lipids for example. “Arsenate in lipids would be stable,” he says, and would “not fall apart in water.” What appears in Wolfe-Simon’s gel-purified extraction to be arsenate DNA, he says, may actually be DNA containing a standard phosphate-based backbone, but with arsenate associated with it in some unidentified way.

Microbiologists over the past few decades have discovered bacteria and archaea in increasingly hostile places, such as hot springs and deep in Earth’s crust. This has spurred on the hope that other worlds (e.g. Mars, Titan) also have places that would be suitable for bacterial life. The possibility of bacteria that can live with a chemical foundation other than CHONPS indicates that life might thrive in places where we otherwise would not have expected it to.

This discovery may not completely redefine life as we know it, but it does (if proven to be true) add one more bizarre thing that life can do.

Grace and Peace

NASA going nowhere?

From Yahoo! News: Senators to NASA chief: Go somewhere specific

President Obama’s budget proposal would axe NASA’s planned trip to the moon. So where should NASA send astronauts? The long-term goal is to send astronauts to Mars, but what are good shorter-term objectives?

Here are two items that caught my attention regarding a future trip to Mars:

  • Using inflatable spaceship parts
  • Technological advances that would cut travel time to Mars down from three months to “a matter of days.”

On a humorous note, NASA has a graphic that shows possible destinations to send astronauts in upcoming years. I’m not sure that “Sun” is all that good of an idea.

Credit: NASA

Grace and Peace

A cheaper way to get humans to Mars: One-way tickets

MarsAstronauts
Credit: NASA

NASA’s Astrobiology Magazine has the text of a presentation given by physicist Paul Davies: A One-way Ticket to Mars.

The greatest expense in sending a group of astronauts to Mars is actually getting them back to Earth. Davies estimates that we may be able to save up to 80% of the costs by sending a group of four astronauts to Mars and then just leaving them there.

At first, this might sound crazy, but how different is it than when my great-grandparents left Norway for the United States, never to see their families again? Granted, Minnesota had oxygen and farmland (but my grandparents eventually ended up in Ekalaka, Montana, which may not have been all that different than ending up on Mars).

The astronauts would end up staying on Mars as the first members of a colony, with the hope that more astronauts would arrive every few years.

“As Bob Zubrin [founder of the Mars Society] has pointed out, Mars is the second-safest place in the solar system. And so it’s the one place humans can go where we could actually make a living, because it’s possible to use material on the martian surface, and crucially, Mars has water and carbon dioxide. So you’re not saying to the people who are going on this one-way mission: you’ve got three days’ supplies and that’s it. You could also protect yourself from some of the worlds hazards, such as the hazard of thin atmosphere.

“I would envisage probably four people would go in the first instance. But a one-way mission to Mars would not just be a one-off exercise. They would be trailblazers. It would be the first step to establishing a permanent human presence on another world. Although they would go without the expectation of returning, they would have the expectation that sooner or later they would be joined by others and that this Mars base would grow and eventually become a permanent Mars colony that might take hundreds of years to establish.”

Anyone want to sign up?

Grace and Peace

More Martian gas

Yesterday I wrote briefly about the ongoing release of methane from the crust of Mars. This is the topic of today’s Astronomy Picture of the Day:

NASA
Credit: NASA

Here’s the description from APOD:

Why is there methane on Mars? No one is sure. An important confirmation that methane exists in the atmosphere of Mars occurred last week, bolstering previous controversial claims made as early as 2003. The confirmation was made spectroscopically using large ground-based telescopes by finding precise colors absorbed on Mars that match those absorbed by methane on Earth. Given that methane is destroyed in the open martian air in a matter of years, the present existence of the fragile gas indicates that it is currently being released, somehow, from the surface of Mars. One prospect is that microbes living underground are creating it, or created in the past. If true, this opens the exciting possibility that life might be present under the surface of Mars even today. Given the present data, however, it is also possible that a purely geologic process, potentially involving volcanism or rust and not involving any life forms, is the methane creator. Pictured above is an image of Mars superposed with a map of the recent methane detection.

This discovery was actually made using Earth-based instruments, not instruments on orbiters. Scientists are already looking into means of determining the isotopic composition of the methane (the ratio of carbon-12 to carbon-13) to gain additional clues as to whether this methane is produced by biological or geological means. Biological processes fractionate carbon isotopes in a slightly different ratio than non-biological processes, at least on Earth. Isotope fractionation occurs because molecules having slightly different mass have slightly different physical properties. For example, heavy water (H2O made with hydrogen-2) has a slightly different boiling point than ordinary water (made with hydrogen-1). Likewise, methane made with carbon-13  has slightly different properties than methane made with the more abundant carbon-12.

Mass spectrometers, the instruments used to measure isotope ratios, are too heavy at present to place on landers. There are, however, spectrographic methods that can be used to determine isotopic ratios, and it is possible that these instruments could be placed on future probes to Mars.

Grace and Peace