Crowlspace

Creationism, of the recent variety, has some odd variations which can, arguably, be compatible with straight science teaching. Firstly, there’s the new view in “Creation Ministries International” (the rebadged “Answers in Genesis”) that God slowed Earth, and maybe the Solar System’s, apparent time down so that the light from distant stars had real time to travel to Earth from billions of light-years away. John Hartnett, the propagator of this new idea, is a trained physicist with a penchant for weird cosmology - he’s a fan of the work of astronomer Harlton Arp, who is notorious for odd ideas about quasars being “proto-galaxies” spat from nearer regular galaxies. Thus all the evidence for an ‘old’ Universe is real, but isn’t real for planet Earth.

His cosmology presented…
A New Cosmology

Some of his papers… arXiv.org Search on John Gideon Hartnett

Unfortunately for CMI and Hartnett the evidence for age written in lakebed sediments and cosmic-ray traces in rocks and trees, is undeniably much greater than the 6,000 years of post-Edenic time attested in Scripture. The adamantine nature of this data led the Institute for Creation Science’s radiometric dating expert, Gerald Aardsma, to leave the ICR under rather acrimonious circumstances - bad for business I guess. But Aardsma didn’t lose faith in those 6,000 years - he found an extra 1,000 in the Bible, and became “The Biblical Chronologist” with a wholly different take on geology’s pesky timeclocks.

Basically Aardsma proposes that geological and prehistoric time is “virtual time”… what could he mean? Here’s a FAQ answer…

Virtual history is not a hard idea. Just think about what it means to actually CREATE something. Creating a story is a helpful analogy. Take “The Hobbit” as an example of a created entity. Now step into the book with Bilbo on page one and begin to examine the world around you. Everything you see and examine around you has already, on page one, an extensive built-in virtual history. Bilbo is in his 50’s as I recall. So he has a virtual history. His house has been dug back into the hill, implying someone did some digging. If you examine the tunnels you can no doubt find tool marks left by the workmen. His front door is made of wood, implying trees grown, sawn into planks, planed, and fastened together by craftsmen, all before the story begins. And on and on it goes…Bilbo’s clothing with all those stitches, and the soil in his yard and garden with humus from long-dead leaves, …

We are living in a CREATION. The creation we are living in is a story of God’s making. It opens on page one 5176+/-26 B.C. (by my best reckoning so far). The story moves from Creation to Fall to Flood to Exodus to Birth of Christ to Crucifixion to Redemption to ultimate Restoration of all things. This story is our reality, but it is not ultimate reality. (God is ultimate reality—He transcends the story just as any author transcends their created story.) And like any story, it has, necessarily, a virtual history built in from page one onward.

The big take-home point is that evidence of virtual history—of even millions or billions of years of this or that process operating in the past—does not and cannot falsify the fact of creation in a created entity. So we can let the virtual history data about the Grand Canyon or the ice ages or whatever else speak for itself and say whatever it seems to say. We do not have to resort to foolishness (e.g., denying the validity of tree-ring calibrated radiocarbon dates) to try to wipe out every trace of any natural process prior to the biblical date of Creation. We understand virtual history to be part and parcel of any created thing, so evidences of such processes do not threaten our faith or falsify the Bible’s claim that we got here by supernatural creation just over 7000 years ago.

Sincerely,
Dr. Aardsma

From here… Virtual History

So do we believe our senses or a certain interpretation of the Bible?

You might ask “Ocean? Surely it’s still there where it’s always been?”

For the last 500 million years that has been more or less true, though sea levels have varied substantially, but in general things have been as always. But before that? A news bite from PhysOrg suggests evidence that a lot of seawater has ended up in the mantle. Part of the ocean has drained away. This would have had dramatic effects on the available land-levels and the potential for Life to benefit from shallow water - much of the deep ocean is desert, feed only by what is produced in the continental shallows. It may be no coincidence that the first macroscopic life, seaweed/macroalgae, appeared some billion years ago.

Looking back in Net-Time there’s also this curious research by some Japanese geoscientists…

Leaking Earth could run Dry

…a BBC news-bite from Sept 8, 1999. But still pretty much on the money. Shigenori Maruyama and colleagues estimated that sea-levels had dropped by 600 metres in the last 0.75 Gyr and the oceans would be gone in another billion. More or less in line with the new research that suggests half Earth’s water has drained into the mantle since the ocean formed. While that might sound like a lot it’s a depth of 5.3 kilometres of water, when averaged over the Earth’s surface. Just 0.25% of Earth’s total volume and the mantle’s total volume is 83%. Thus a drop of water in a bucket of lava…

Addendum
Eldridge Moores, a Professor Emeritus of Geoscience, has suggested for some years that sea-levels have declined over geological time, though due to a different process. By his reckoning the oceanic crust was thicker and thus isostasy meant the average ocean depth was shallower - meaning all that water covered the continents too. Only mountain peaks poked above the waves. Then, roughly as Rhodinia began forming, the thicker crust gave way to thinner oceanic crust and that super-continent of the day rose from the waves over the next few hundred million years.

When Earth Dried Out

How many times have I heard people fretting over the Solar Wind blowing a planet’s atmosphere away when talking about the terraforming of Mars or the Moon. People… not going to happen in a hurry. The Solar Wind is on average 5 million particles (mostly protons, just like the Sun) per cubic metre travelling at 400 km/s at Earth’s distance from the Sun - thus the flux (number passing through per square metre) is 400,000 m/s*5,000,000 /m^3 = 2E+12 protons per square metre per second. Their collective energy flux is their kinetic energy times their number flux - i.e. 1/2*(400,000)^2*(2E+12)*m(p)… where m(p) is the proton mass (1.673E-27 kg)… so we’re talking 2.68E-4 J/s. Less than 0.3 milliWatts per square metre. The sunlight is 1365 W/sq.m some 5.1 million times stronger, but qualitatively the two are quite different in how that energy is distributed. A proton slamming into an oxygen atom at 400 km/s is quite a bump. If all the momentum went from proton to atom, the atom would fly away at 25 km/s. But ions and atoms tend to collide elastically and bounce off each other. To conserve momentum and energy, the proton reverses direction and slows a bit, while the atom is flung away at high speed. But when trillions of atoms and ions are involved it’s not just one interaction - many could occur and eventually the ion might share its momentum with quite a few oxygens before escaping to space. So there’s three outcomes - one interaction between ion and atom, an even share (on average) of ion momentum, and finally an even share of ion energy. Surprisingly the first is the least efficient - an upper Venusian atmosphere some 6,200 km in radius loses just 6.4 kg/s. The second case loses 2.5 atoms (assuming 10 km/s escape speed at altitude) per ion - thus 16 kg/s. The third case sends 100 atoms into the void per ion - 640 kg/s. Sounds respectable but Venus has 4.6E+20 kg of gas to space… meaning 2.3 trillion years, 0.911 trillion years and 0.023 trillion years respectively to lose Venus’s air via the solar wind. A long time.

So why is Mars described as losing all its air in the early days? Back when the Sun was young its Wind was up to 1,000 times stronger. Mars, being smaller than Venus, would lose its air very rapidly in those days (Venus would still take billions of years in scenario 1 &2), but not now the Sun is better behaved. There are complications to this picture too - magnetic fields and ionization of the impacted atoms - but the basic picture is pretty straightforward. Solar Wind erosion is SLOW…

Recent years have seen a lot of optimistic reappraisals of the requirements for space elevators - instead of multi-billion ton structures anchored to asteroids the current designs mass less than 1,000 tons and can support 20-ton elevator cars. However there are a few problems, one of which I’ll discuss here: How to power it? If you’re observant you might notice I’ve written a few thoughts on this issue before but a few modifications of my first discussion are necessary.

Firstly, a potentially high efficiency solar-thermal conversion system is doable using a Johnson Thermoelectric converter - basically a closed-cycle fuel-cell that is aiming for an 85% of Carnot Limit efficiency. But what does that mean? Carnot efficiency is basic to thermodynamics - it’s the extractable work from a cyclical thermal process. In this case a fluid is heated by concentrated sunlight, goes through the converter then through a heat-sink, then returns to the concentrator. When it comes to dumping “waste” heat in space the hotter the heat-sink, the better. I’ve seen 600 K quoted so often it’s what I’ll assume. The Johnson converter is hoped to operate at 1300 K, thus the Carnot Limit is (1300K - 600K)/1300K or 0.5385. Thus the Johnson converter can turn 45.77 % of the heat directly into electricity, and 54.23% has to be dumped by a heat-sink to space.

How much power is needed? Assuming the 20 tons usually quoted for the ribbon-crawler, then to lift-off at a sustained 56 m/s straight up needs a lifting-power of 11 MW - which means about raw 12.2 MW electrical power with 90% efficiency in the power supply and motor systems. That means 26.7 MW of solar heat needs to be collected. If we assume the solar constant, 1365 W/sq.metre, then our collector is 19,560 sq.metres. Our heat sink, which at 600 K is radiating 7350 W/sq.m from BOTH sides (assuming a flat radiator), is 985 sq.metres. The solar collector, focussing on a converter at 1300 K, means the sunlight is being concentrated by a factor of ~120 times, thus the heavier thermal converter has an area of just 165 sq.metres (assuming all collectors and radiators are close to being perfect black-bodies.)

How big is 19,560 square metres? Almost 5 acres - if it was two circular collectors they would have a diameter of 158 metres each. Big, but doable with large inflatables, which is easy to do in space. However for about 60 km or so the crawler isn’t in space, and inside the atmosphere, with ravenous winds, big solar collectors aren’t practical. So what to do?

Current designs assume high powered lasers, but the efficiency of lasers is dreadful - less than 20% of wall-socket power becomes laser beam energy. Assuming the 12.2 MW at the crawler, about 85% conversion efficiency from laser light, then the crawler’s laser light receivers are taking a beating of ~14.4 MW of laser energy, and the ground base is pumping 72 MW of electrical power into the lasers on the ground - or worse, depending on atmospheric absorption. Still the laser receivers don’t have to be really huge - if they’re dissipating the waste heat at 500 K, then twin receivers would only 20 metres in diameter each.

But what if we can get above the atmosphere before inflating the collectors? To power that climb - 60 km - we need a sufficiently energy dense power source to do the job. First question: could it be done with a petrol engine? As air thins out in a hurry it would need oxygen tanks for at least part of the trip - a big part probably. Also the power the engine would need to supply would be over 13,000 horsepower, which would be quite an impressive engine. Obviously it would be a gas turbine as that’s the only design regularly built at such power-levels - they’re frequently used to provide peak power by electrical utilities in the multi-megawatt range. At 35% efficiency thermal efficiency and 90% power conversion efficiency then the 13,000 hp of electrical power means a 42,000 hp gas-turbine… which is starting to get seriously heavy. Good-bye 20 ton crawler.

So what about EEstor ultra-capacitors? According to Wikipedia’s latest update on EEstor they’re now claiming about 2.5 MJ/kg energy density. If we assume 0.9 efficiency electrical-to-mechanical power efficiency and 0.9 from battery-to-motor then a 60 km trip at 56 m/s straight up needs 14.55 GJ of energy - some 5,820 kg of capacitors. Not bad and improved by a “booster crawler” that carries the main crawler to the desired height, then rolls back down while regeneratively braking and recouping some of the power.

So, if EEstor’s claims pan out, then the Solar-powered space-elevator might just be viable.

The ESA pulled off its first asteroid flyby on the Rosetta comet-probe mission…

Steins: A diamond in the sky

…after an Earth gravity-assist maneuver, 13 November 2009, another asteroid, 21 Lutetia, is due for a flyby July 10, 2010, and the target comet, 69P/ Churyumov-Gerasimenko, will be reached in c. May 2014. The HST has taken “close ups” of the target comet, revealing a nucleus somewhat larger than the original target, Comet Wirtanen, but the comet lander should be up to the task just fine. There are also computed images images of 21 Lutetia from its lightcurve… Thirty Main Belt asteroids from their lightcurves …though such guesstimates should be taken with a grain of salt.

The Carnival of Space is on at Discovery Space Blog and it’s in alphabetical order, just for something different. No contribution from moi this week as I’m mulling over different bits of space news and trying to write an essay about a new theory of Lunar origins, but was sidetracked by the recent discovery of variable radioactive decay. The Jenkins-Fishbach Effect is a variation in radioactive decay that seems to be correlated with the Sun’s activity - no one has a good theory for what might cause it (if it’s a real correlation) so there’s several competing models, one being variable neutrino flux from the Sun. It’s interesting and potentially explains the very difficult C-14 dating anomalies (for example the fact that C-14 dates between 800 and 400 BC all give the same answer.)

If the variation is neutrino driven then objects on eccentric orbits will show different decay histories and potentially more (or less) heating. Mercury, for example, has an eccentricity of over 0.2 and thus its orbital variation in insolation is very high. Has its radioactives decayed differently to Earth’s and the Moon’s?

Sky survey yields new cosmic haul …including a new Inner Oort Cloud member - making two, the first being Sedna.

Solar plane makes record flight …stays aloft 3 days by recharging lithium-sulfur batteries via very light-weight solar cells. It cruised at 18 km up (temp -70 C, pressure 0.075) and is hoped to be a battle-theatre “Eye in the Sky” or a civilian comms-platform. The company is hoping for 5 year flight-times for a large version - carrying 450 kg versus the 2 kg payload on this bird.

An end to spaghetti power cables …MIT demos power transfer via magnetic induction resonance with 90% efficiency over 1 metre. Enough to get rid of cables in the home.

Stellar Still-births …brown dwarfs are aborted stars - low mass objects perturbed out of a trinary birth-nebula. Thus they’re a cosmic class of their own.

Genome of simplest animal reveals ancient lineage, confounding array of complex capabilities …placozoans, Trichoplax, share a lot of genes and introns with both cnidarians and bilaterians, even us humans. And there’s at least 13 species now distinguished by these researchers… something to update all the web-pedias which still say there’s just one, plus a maybe. Not so, and a quick Google reveals a few papers to that effect since 2003… come on people! Pick up your game!

Exploding Chromosomes …because DNA has one charge along its length it can’t be wound up tight without some help. In humans it’s histones, big molecules, but in dinoflagellates it’s just sodium and calcium ions. A neat trick with some lessons for the prehistory of genomes.

One Man’s Crater Quest …a New Jersey native, Daniel Connelly, is trying to interest professional geoscientists in a gigantic crater smack bang in the middle of Australia. Problem is it’s a bit hard to see. He’s been roving the Outback trying to gather evidence - he’s convinced and has convinced his wife, a physician, but the pros aren’t biting yet.

Mercury is half a Mars. It’s 2/3s iron-alloy core and has an uncompressed density of 5.3 (Earth is just 4.08), which makes it the densest planet. But it is so close to the Sun that it is also the fleetest, thus not showing any signs of being overly leaden. At a mass of 0.0553 Earths (Mars being 0.10745) it very nearly is half a Mars, but packed into a volume of 37.3% of Mars. Thus it is Mars missing its upper mantle. Like Mars it has polar caps, revealed by RADAR in the early 1990s. Its sidereal rotation period (’day’) is 59 days, while its year is 88 days - a ratio of 2-to-3. Thus its solar day, or sol, is exactly 2 years or 3 ‘days’ long. Its eccentricity is 0.205630, so its orbit (a = 0.387098 AU) varies from 0.466697 AU to 0.307499 AU, and its insolation from 4.59 Earths to 10.58 Earths, thus making its surface temperature range from 558 K to 688 K at its subsolar point. However its rotational axis is almost perpendicular to its orbital plane - thus it has no seasons, and its polar regions stay much cooler on average. Near the Poles it only gets as hot as Earth’s Moon, and the vast shadows of its polar craters remain cold enough for ice to accumulate, apparently lofted there as water vapour by its very thin atmosphere.

Mercury also has a dipole magnetic field akin to Earth’s but weaker. Thus its surface is protected from the raw solar wind, though its arctic regions must encounter a lot of ions, perhaps combining the protons with surface oxides to make water. The recent visit of “Messenger” (first flyby of three before orbital insertion) also spotted several volcanoes, indicating occasional eruptions of volatiles from within - most likely sulfur compounds and water - which will migrate to the poles, perhaps before being snatched away by the solar wind. Thus the ice-caps might be an acidic mixture, with benefits for any colonization efforts. Life can not live on plain water alone.

Because Mercury’s core is relatively accessible will that make it a desirable object for mining efforts? That seems reasonable because Mercury has large amounts of solar energy too, to power mineral extraction, refining and export. Yes, export. A next-to-nonexistent atmosphere and lots of sun means Mercury is perfect for gigantic mag-lev launchers. Also its proximity to the Sun means that Hohmann transfer windows are relatively frequent to ALL the other planets. Here’s some transfer times for Hohmann, Elliptical and Parabolic orbits…

Planet	Distance	Hohmann	Elliptical	Parabolic
Venus	108.2	75.54	39.54	23.79
Earth	149.6	105.47	55.68	38.06
Mars	227.9	170.49	90.16	67.11
Ceres	413.9	361.67	190.15	149.70
Jupiter	778.6	853.73	445.30	359.60
Saturn	1433.5	2032.43	1053.88	860.59
Uranus	2872.5	5597.78	2890.44	2374.36
Neptune	4495.1	10841.1	5588.60	4600.00

…times in Earth days, distance is to the Sun in millions of km. Orbital transfers are computed from Mercury’s average distance to the Sun, to the target planet’s average, thus it varies a bit depending on actual position. A Hohmann orbit is the minimum energy transfer - exactly half an orbital ellipse from one planet to the other. The elliptical is a segment of a transfer ellipse, in this case a quarter of the ellipse (i.e the target planet’s radius is equal to the transfer orbit’s semi-major axis.) And the parabolic is a Solar escape orbit. As you can see the transit times are pretty rapid for the inner planets, as orbits go. Venus is mere weeks away and even a trip to Jupiter is under a year for a parabolic orbit. As we’re talking bulk cargo this probably isn’t odious with sufficient planning. Faster trips, for personnel, will need much higher energies.

So, in theory, Mercury could supply metals to all the inner planets and the near asteroids. You might wonder: why couldn’t the metal asteroids supply the rocky asteroids more quickly? Surely they’re closer?

Problem is that asteroids aren’t continually in convenient positions for a minimum energy transfer. Take Ceres (rock/ice) and Vesta (rock/metal), some 2.767 AU and 2.362 AU from the Sun respectively. Ceres takes 4.6 years and Vesta takes 3.63 years to orbit the Sun. Between transfer windows is, on average, over 17 years because their orbital periods are so close together. Yet Mercury’s windows to Ceres open up every 0.254 years. Thus it’s easy to see the advantage. Of course things are a bit complicated by the orbital eccentricity of both - Ceres’ is about ~0.08 - but the principle remains the same. That and sunlight that’s 37 times stronger on average.

Omo man, from some 200,000 years ago, was hailed as the first Homo sapiens when first discovered 41 years ago. Since then his affinities have broadened somewhat, as more bones were recovered, and palaeoanthropologists are likening “Adam” to Homo neanderthalis and (African) Homo erectus…

Earliest Known Human Had Neanderthal Qualities

…as reported by the Discovery Channel. His face shows robust features, while his limbs and feet resemble the Erects and Neanderthals. This might indicate that many of the features of the elder species are actually lifestyle wear-and-tear rather than genetically transmitted features. Certainly “Adam” is so similar to modern humans that he is being likened to the people who still reside in Ethiopia today.

Welcome to the Carnival of Space, brought to you this week by Crowlspace and the never-tiring efforts of Fraser Cain and Universe Today. First cab off the rank is musings by Paul Gilster (Centauri Dreams) who ponders the difficulty of interstellar travel as depicted by Robert Frisbee who brings us the 160 million ton antimatter powered starship (see this old “Discover” magazine piece Star Trek for more details.) “Crowlspace” also covers Frisbee’s rather gloomy prognostications here… Antimatter Ain’t What it Used to Be

Also on theme Brian Wang’s Next Big Future gives another viewpoint on the difficulty of antimatter rocketry and the relative ease of leaving the engines at home and riding a beam… Interstellar Prospects

Next Nancy Houser of A Mars Odyssey ponders the dangerously variable magnetic field of the Earth… A Newly Found Dent in Earth’s Protective Bubble…. Dr.Ian O’Neill puzzles over the folly of media hyping of a radio detection of the Galactic Core… No, An Alien Radio Signal Has Not Been Detected.

The Bad Astronomer blogs at “Discover” magazine on why telescopes haven’t been used to disprove the “Moon Hoax” claims… Moon hoax: why not use telescopes to look at the landers? (as if astronomers don’t have better things to look at anyway!)

Dr. Bruce Cordell of 21st Century Waves draws on the the Lewis and Clark expedition (almost as arduous as a trip to Mars) to get perspective on current space exploration hopes… 10 Lessons Lewis & Clark Teach Us About the Human Future in Space.

From Out of the Cradle just in time for back to school (in the Northern Hemisphere that is), Ken Murphy reviews the new ‘Kids to Space Mission Plans’ designed for teachers and homeschoolers who want to add some space-themed activities to their classrooms… Take an Educational Field Trip to the Solar System. Wish I’d had that 6 months ago

Darnell Clayton’s Colony Worlds poses a pungent conundrum for interplanetary colonisation… Living Off World May Stink … our dreams of humanity expanding throughout our native star system may ultimately come to naught, due to the simple fact that living off world may irritate one of our key bodily members, also known as the nose.

This week David Portree’s Altair VI promotes a new facility for public and professional researchers he’s just opened at the US Geological Survey Flagstaff Science Center:

We Have Liftoff

He also looks at a novel approach to Mars sample collection put forward by Alan Stern in 1989.

Mars Tethered Sample Return (1989)

Ray Villard’s Cosmic Ray asks if arguing over Pluto’s status as a “real” planet is worth the hype… Spirited Pluto Battle, But a Great Debate? Once upon a time there were only 7, including the Sun and Moon. How things change!

OTOH Emily Lakdawalla argues maybe anything studied by “Planetary Scientists” should be called a “planet”… Things that probably won’t ever be called planets, but maybe they should

Simostronomy (Mike Simonsen) looks closer at the good news and the bad news out of a recent cosmogony simulation… Planets - Good News, Bad News …which found only 1 solar system like ours out of 100 simulations. Terrestrial planets form easily it seems, but not in solar systems like our Solar System.

New & Noteworthy at the LPI Library gives us an update on recently available Astrophysics related resources, including the new Portal to the Universe.

The Phoenix Mars Polar Lander spied frost for the first time this week… Phoenix Sees First Frost …courtesy of The Meridiani Journal.

Ian Musgrave, the Astroblogger says Kopf Hoch! Raise your heads people and Look! I did and I saw Venus and Mercury together at sunset yesterday.

Stuart Atkinson, of Cumbrian Sky gives us… Narnia Mars

Bruce Irving’s Music of the Spheres looks back on the Earth from deep space… Distant Mirrors (and Cribsheets)

Aloha Carnival! Says A Babe in the Universe, Louise Riofrio. Last week the Cassini spacecraft made a close flyby of Saturn’s mysterious moon Enceladus: Enceladus Flyby …Cassini was able to localise sources of the water geysers erupting from the South Pole. More heat comes from this little moon than can be produced by tidal
forces or radioactive decay. Louise speculates about other causes, even a Black Hole.

And that’s it for this week! Enjoy, be enlightened and (if you’re in the USA) vote for the right person to lead the Spacewards Vanguard… whoever that might be