Tag Archives: Astronomy

Apply Spf INFINITY to Appropriate Areas


A previous post on the subject of human space travel was cautionary, and I did not leave much hope (?) to those who truly desire to visit Mars, the asteroid Ceres, or even walk in the footsteps of the intrepid Apollo astronauts. The following post is my attempt to survey the efforts of protection so that we too may gain that unique perspective.

Space travel will, one day, be routine for many on our planet; and the current period of economic hardship in which scientists and those in public outreach endure will be perceived as if it were adolescence. I believe one can see the evidence in the trends which appear cyclical. Although I have no real hard data to work with—most sociologists and economists will cite the cyclical nature of political fortunes. (In a nutshell—those with money make the rules and everyone acts in their own self-interest.)

How does one shield oneself from space radiation?

There are two forms of space radiation: solar and galactic cosmic rays. Given we know how cosmic and solar radiation interact with earth-bound substances, we are several steps ahead of by knowing to protect ourselves. Basically, our “engineers” must have a fundamental understanding of materials science (e.g. plastic, metal, glass, fiber, and people, too).  The concepts of how radiation (nuclear physics) interacts with atoms, bonds and molecules (or the things of our everyday lives) is tantamount to knowing how to survive in space.

We (on Earth) put sunscreen to protect our skin (?) but there is more to the picture. Just like we know that it may take multiple sunburns to eventually contract fatal cancer; in space, the concept of amount of exposure is multiplied many times over. Exposure to intense X-ray radiation (for a mere 20 minutes) may lead to acute radiation sickness. There is no (?) sunscreen lotion to protect us from harsh solar X-rays or galactic radiation, for that matter.

What we have is a rich historical past to draw our lessons of shielding. Our past missions (manned and un-manned) have given us precedent to use the following materials:

  • Aluminum—
  • Plastic such as polyethylene—
  • Non-reactive internal equipment—
  • Nano-fibers—
  • Hydrogen fuel

The last citation may seem odd but it (hydrogen fuel) has been a source of shielding. In fact “hydrogenous” materials (e.g. water) have been the basis for  shielding. Specialized (nano-fiber) blanket and coats have been used, as well.

In the final analysis, our first spacefaring citizens will take away a memorable excursion and will be considered intrepid pioneers, in some sense of the word.

Reference for post:

Durante, M. Physical basis of radiation protection in space travel, Reviews of Modern Physics, 2011, 83, 1245-1281

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Generalities of Science Ethics, Life in the Goldilocks Zone, and the Allan Hills Meteorite


INTRODUCTION

The years 1996-2000 were interesting to the astronomy community for many reasons. Many will remember the pronouncement of Martian fossilized life and the huge groundswell of commentary that the Allan Hills meteorite garnered. And, it was during those years that NASA announced the past presence of water on the Martian surface. Thus it would seem, the two (life and water) would go hand-in-hand. And, I was one of the converts who wanted to believe in the veracity of past life on the red planet. Since that time I have often wondered to myself—why did the ALH84001 finding not hold-up as well as it might? During the time period I recall reading many research reports on the on ALH84001. And as many can attest, all too often a lack of good, scientific judgment may be based upon a pre-conceived belief system that has no scientific foundation. Supporting the galling belief system is the self-perpetuating rationalization: a lifestyle which subconsciously massages egos. Perhaps, it is a sign of professional growth when one can understand that certain patterns of lifestyle can undermine good, scientific judgment. So, I ask, which way to turn?

FOLLOW THE WATER, THE ENERGY, or BOTH?

Simple Corollaries for Life’s Presence and Evolution . . . Why?

  • Life requires a solvent—but it may not always be water
  • Life requires energy
  • Solvation and Energy generally act in a synergistic manner

Our, Earth-like, lives are heavily tilted towards water and the simpler elements on the periodic table. One primary reason is the energetics, and the meaning of the supposition might be summarized in the following manner—our habitable zone is synergistically shaped between ourselves and the environment in which we live. Try to imagine (for the moment) if our (?) Sun was an F class star and not G class. A primary difference is the temperature of the new Sun—one could surmise that the chemistry would be different, as well. And, quite possibly, silicon-based life may arise—using the carbon analogy of periodicity within the table of elements. (Although the presumption sounds deceptively simple, the chemistry is far from simplistic. See the following link for a podcast for a consideration on weird chemistry–Limits of Organic Life.)

It might, well, be speculated that water could serve the role that oxygen serves in our current milieu—and even metal back-bonding would replace the ubiquitous hydrogen-bond. Although the above-mentioned scenario seems fantastic—one may take into account that there may not be one good, realistic definition for non-carbon life. Thus, as current paradigms of carbon-based biochemistry seem to limit our vision of life—the need to expand efforts in basic research in inorganic models utilizing realistic energy cycles could open new venues for biochemical research.

Some references of note:

Lilia Montoya, Lourdes B. Celis, Elías Razo-Flores, Ángel G. Alpuche-Solís. 2012. Distribution of CO2 fixation and acetatemineralization pathways in microorganisms from extremophilic anaerobic biotopes. Extremophiles 16:6, 805-817.

Charles H. Lineweaver, Aditya Chopra. 2012. The Habitability of Our Earth and Other Earths: Astrophysical, Geochemical,Geophysical, and Biological Limits on Planet Habitability. Annual Review of Earth and Planetary Sciences 40:1, 597-623.

C. S. Cockell. 2011. Life in the lithosphere, kinetics and the prospects for life elsewhere. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369:1936, 516-537.

Jorge Rodríguez, Juan M. Lema, Robbert Kleerebezem. 2008. Energy-based models for environmental biotechnology. Trends in Biotechnology 26:7, 366-374.

Niles Lehman. 2008. A Recombination-Based Model for the Origin and Early Evolution of Genetic Information. Chemistry & Biodiversity 5:9, 1707.

Murchison Meteorite


MURCHISON METEORITE—A WELCOME VISITOR

by

John Jaksich

As the world was celebrating the Apollo moon landing in 1969, humanity was greeted by a visitor—and a very welcome one, at that. On the morning of September 28, 1969, Australians witnessed a meteorite fall in Murchison, Australia—this piece of space rock has become one of more celebrated visitors from space (second only to the ALH84001, the Alan Hills Meteorite).

By Art Bromage  via Wikipedia

By Art Bromage via Wikipedia

 Murchison Meteorite

The Murchison meteorite is celebrated for many reasons, mainly of course; the detailed analysis of its constituents has yielded a treasure trove of data and some speculation, also. Firstly, speculation is, at times, part of the human condition—so I will put it aside.

Technically, the Murchison meteorite is known as a carbonaceous chondrite and it said to be about as old as the Solar System, itself. But, one major, distinguishing feature of this rock is the amount of organic compounds that have been identified within its matrix. According to two publications (listed below), it contains up to several thousand different organic compounds (many of the compounds may have some biological significance). Although it should be emphasized that no DNA, RNA—or fossilized remains of any type of organism were found within the Murchison meteorite.

The organic compounds, just the same, are very significant because many of these molecules yield important clues as to the nature of the protostellar disk—the type of chemistry which was prevalent before life took a foothold in our Solar System.

There have been skeptics—many of whom voiced legitimate concerns: contamination of the “rock” with terrestrial organics, ablation of meteor—resulting in significant alteration of the meteor, and “bad” handling processes by scientists and technicians. All the publications (three are listed below) which I have studied seemingly address the issues.

What does all of this mean? Molecular constituents that bear a resemblance to life’s constituents were “here” –in the protostellar disk, prior to us, prior to the dinosaurs, prior to the formation of our planet. That is a significant finding from a scientific point of view—almost (but not nearly close enough) as if we had found microbes on Mars, Europa, Enceladus, or Titan. Perhaps, it anything, this can serve as a rallying point for those of us who believe in science and its pursuits.

Publication reference list:

Schmitt-Koplin and others, 2010, Proceedings of the National Academy of Sciences.

http://www.pnas.org/cgi/doi/10.1073/pnas.0912157107

Pizzarello and Shock, 2010, Cold Spring Harbor Perspectives in Biology.

(Cold Spring Harbor Perspect. 2010;2:a002105)

Callahan and others, 2011, Proceedings of the National Academy of Sciences.

http://www.pnas.org/cgi/doi/10.1073/pnas.1106493108

Please note that you may have to pay for access—these references are copyrighted.

EINSTEIN in POPULAR CULTURE


OPINION and FACT—EINSTEIN in POPULAR SCIENCE

by

John Jaksich

Astronomy is indebted to Einstein; and in many ways, he helped propel the subject of astrophysics to the forefront of the public’s consciousness. Replacing Newton’s paradigm of gravity was no easy task, either. In my very humble opinion, his ranking stands with Newton and Archimedes for outstanding scientists. And, although there have been many outstanding scientists who walked upon the Earth in the past 3000 years, my reasons for those three are (to me) simply justified. Not only did each individual have revolutionary ideas, but each invented a new mathematical insight to explain the Universe—a better way to quantify a physically difficult concept. (Whether or not any “current” scientists achieve that pinnacle—is uncertain.)

By Photograph by Oren Jack Turner, Princeton, N.J. (The Library of Congress) [Public domain], via Wikimedia CommonsYear 1947

By Photograph by Oren Jack Turner, Princeton, N.J. (The Library of Congress) [Public domain], via Wikimedia Commons
Year 1947

Einstein’s insights into gravity and cosmology appear mathematically foreign to most of us uninitiated with Tensor Calculus. His approach is distinctly algebraic, but the shorthand is primarily geometrical. The latest (?) findings—or postmortem photographs of his brain—tend to lend credence to his purported geometrical reasoning processes.

Perhaps, one way to appreciate his many discoveries is to attempt to sift through his publications. According to Wikipedia, (see link at end of blog), and the Einstein archives co-hosted by the American Physical Society and the Hebrew University of Jerusalem, the topics of scientific publications range from thermodynamics, magnetism, electrodynamics, quantum mechanics, statistical mechanics to (of course) relativity. His reported aversion to quantum mechanics may be traced (possibly) to his personal philosophy of “a determined Universe.” In short, he was unable to reconcile the statistical nature of quantum mechanics with his view of the cosmos. One little known fact is his patent for a noisless-refrigerator—cooled through an electro-magnetic pump (see link at end of blog.)

credit Wikipedia and U.S. Patent Office

credit Wikipedia and U.S. Patent Office

Important Links: (please do not abuse)

en.wikipedia.org/wiki/List_of_scientific_publications_by _Albert_Einstein

http://www.einstein.caltech.edu/contact/index.html

patriciahysell.wordpress.com/tag/einsteins-refrigerator/

Stars at Night


INTRIGUED BY THE STARS ?

credit: NASA and Wikipedia

credit: NASA and Wikipedia

by

John Jaksich

Stars such as the Sun possess a beauty, an almost imperceptible attraction that tend to change one’s perspective, once their true nature comes to bear. Perhaps we it owe to Galileo, as he was one of the first to record the sunspots and simultaneously help launch the Scientific Revolution. For instance, upon gazing at the Orion nebula with binoculars, one may gain a sense that the colors observed have a molecular constituency familiar to us all . However, this naïve observation is definitely one which leaves most professors scratching their heads, and muttering: “I wish I had time to instill the truth with this one.” Perhaps, yes? But often times, what may seem like naiveté is an actual burning desire to learn. It is an innate desire to understand more fully, or an underdeveloped yearning to question.

As scientists or would-be scientists, observing the Sun is done very carefully; there are various manners in which to do so. Perhaps, the easiest is to go on-line to one of the various NASA, ESA, or their associated sites and just wondrously and safely gaze at it. The Sun in all of its coverage defines the boundaries of the Solar System; and beyond the boundaries, it is estimated that the closest complex of stars is alpha-Centauri. This three-star system (in the constellation Centaur, the bull) is approximately 4.4 light-years away—and by any standard, it would take multiple life-times to travel to it with the fastest of rockets. For those of us new to “star study,” most stars in the Milky Way are multiple star systems. So, our Solar System is in one word: unique. And, a possible interpretation for our Sun’s uniqueness is: the cradle of the Solar system did not hold enough “matter” to coalesce to form more than one Sun.

Credit: NASA and WIkipedia

Credit: NASA and Wikipedia

So as will astronomers tell you, stars like our Sun or the alpha-Centauri complex were born in places like the Orion nebula. That vastly large volume of gas, dust and light hosts multiple star “conceptions.” For instance, the now-famous Eagle Nebula (also known for the “Pillars of Creation”); one can see a “so-called moment of stellar conception” at the very top of the pillar. Those points of light (or the tips of tops of the pillars) are “multiple solar system-sized volumes” of gas, matter, and energy. When one views the Hubble images of the Eagle nebula, not only are we looking back in time, but we view a vast volume or “size” of space that is mind-boggling. In some ways, I envy our progeny; our future generations may well know how to communicate with those at vast light-years away. But, then that makes me, also, feel rather selfish; as if, I did not have enough to offer of myself to them.

Credit: WikipediaPosition of alpha-Centauri in Southern Sky

Credit: Wikipedia
Position of alpha-Centauri in Southern Sky

CITIZEN SCIENCE


IN PRAISE OF CITIZEN SCIENCE AND COMPUTERS

by

John Jaksich

SETI app

Computational Citizen Science owes its origins, in part, to SETI.at.Home –the computer screen saver that dared anyone with idle computer time to utilize it for the pursuit of searching for signs of E.T. To the few astronomy-literate individuals not familiar with it, this simple adventure commenced with a single computer server in a cramped closet at the University of California, Berkeley in the mid-1990s. This inspirational endeavor born out of the silicon boom, has spawned dozens of well-meaning and educational endeavors. If allowed to continue to evolve, it may solve some of the more pressing problems faced today. Currently, the list of endeavors may be found here. The folks at Berkeley kindly developed the software so it could be adapted to different types of problems. Presently, the software is known as BOINC—or Berkeley Open Infrastructure Computing—and it is free for all to use.

One well-conceived off-shoot to the traditional screen saver has appeared. This undertaking is Cosmoquest.org which was launched in 2011, and is currently headed by five talented individuals in the astronomical community: Dr. Pamela Gay, Dr. Nicole Gugliucci, Scott Lewis, Georgia Bracey, and Joe Rhea. This is, perhaps, one of the more intelligent endeavors to prosper from the citizen science movement. The reason being—in my opinion, is their focus is precise while still having a large following. In mid-2012, the internet forum—Bad Astronomy-Universe Today joined the endeavor, and the group of “internet-inspired intellectuals” has produced a smart, vibrant community.

Although it may sound as if I am “tooting a horn” that may not need publicity, I speak because I have participated in the above endeavors. Why? For the same reason that I feel public outreach and education are the logical path of social networking.

SETI.at.HOME may be found at:  http://setiathome.ssl.berkeley.edu/

BOINC may be found at this link:: http://boinc.berkeley.edu/

COSMOQuest.org may be found here: http://cosmoquest.org/