Category: Super-Tech

Clarke Tech, God Tech and just plain cool

A Particularly Bad Year…

As the World licks its collective wounds after the Financial Meltdown and we all watch the storm clouds gather, consider the Egyptians suffering under the Plagues of Moses way back in c.1500 BC (1300 BC?) Usually written off as fiction, the perfervid imaginings of a pious scribe or two, a recent analysis by Colin J. Humphreys lends the account some credibility when the details are matched against the internal calendar of the account…

The Plagues of Egypt
Plague Cause Time of Year
Nile turned to Blood and fish died Red soil particles and red algal blooms September
Frogs/Toads Pollution forces frogs ashore where starvation and dehydration cause mass die-off September-October
Gnats Biting Midge, Culicoides carnithorix. Predators all died causing population boom. October-November
Flies Stable Fly, Stomoxys calcitrans. Population explosion as above (slower life-cycle.) November
Livestock mass-deaths Culicoides spread Bluetongue and African Horse Sickness viruses. November-December
Boils Stomoxys spread skin infection. December-January
Hail Exceptionally severe hailstorm. February-March
Locusts Damp sand from hail attracts the Desert Locust to lay eggs. February-March
Darkness for 3 days First annual khamsin produces a dark, dense dust-storm. March
Death of Firstborn (males) Mycotoxin on grains, due to grain being contaminated and damp after hail and locusts, and stores being sealed by sand from sandstorms. late March-early April

All these events occurred at the correct time of year and follow logically one after the other. Thus it’s a coherent whole account, not a pastiche of scribal bits and pieces as several venerable compositional theories hold. Either the scribes who wrote it were keen observers of Egyptian natural disasters, and they pieced them together correctly, or the account is describing an actual historical catastrophe. But was it caused by the God of Moses? Or did Moses somehow see it coming and skilfully used the opportunity to march his people into the land of Midian to found a new nation? Is there a difference?

For more on Colin Humphreys’ ideas check out his book The Miracles of Exodus. He’s a physicist by training who became keen on the historicity of the Exodus tale after a trip to the Levant. Not initially a believer in the accuracy of the account his research eventually produced a convincingly coherent reconstruction of Moses’ tale. Annoyingly, direct evidence for Moses remains elusive.

SpaceX… options

Space Exploration Technologies, SpaceX, has numerous rockets on offer. I thought I’d do a handy summary here.

Falcon 1/1e
Falcon 9
Falcon 9 heavy
Dragon

Vehicle LEO Payload (kg) GTO Payload TLI Payload Cost $USD millions
Falcon 1 420 ** ** 7.9
Falcon 1e 1010 ** ** 9.1
Falcon 9 12500 4640 1925 36.75-57.75
Falcon 9 heavy 29610 15010 6230*** 94.5-104.5
Dragon >2500 * * *

* – figures for Dragon are currently not very detailed on the SpaceX page.
** – Falcon 1/1e need a ‘kick motor’ to launch a payload to the Moon. Only the 1e can realistically launch enough mass for a small lander.
*** – no TLI mass is quoted for the Falcon 9 heavy, but if the proportion remains the same as for the Falcon 9 between GTO and TLI, then this is the estimate.

The TLI mass for the Falcon 9 heavy might indicate a luna capability for Dragon with the right heat-shield. A two-launch Luna mission might allow a lander. The old Apollo LM massed just ~ 15 tons, thus combined with a TLI stage, this might allow landing on the Moon. Assuming ~ $210 million for the two launches, and ~ $1.5 billion for the LM (aerospace vehicle development costs ~ $100 million per ton the old way), and you’d have a lander mission for under $2 billion. Cheap!

Chinese Space-Station… coming soon

The next Chinese space-craft, Shenzou VIII and Shenzou IX, will be unmanned – to start with – but the next manned mission, Shenzou X, will dock with one (or more) and form an orbital laboratory complex. In otherwords a Space Station. Attach a couple of propulsion modules and the Lab could be launched Moonwards, forming a Moon-Lab, just like the proposed “Wet-Lab” Skylab II that was discussed in the late 1960s as a cheaper Moon-Lab option.

Chinese News Coverage on the Plan

Carnival of Space Week #72

The Carnival of Space Week 72 is up and running. Informative stuff.

Also informative is this little gem… Space Elevator: Physical Principles …which covers the derivations and consequences of the main physical aspects of a basic space elevator. Written by Ranko Artukovi? of Zadar, Croatia, and definitely worthwhile for all hard-core applied maths freaks and space-nuts.

From impeccable mathematical applied-physics to dubious applied physics we have Brian Wang’s latest on the EM-Drive… Superconducting Radio-Frequency Cavities for High Q …the table he gives makes me rather dubious about the EM-Drive’s utility.

Effect of increased Q for the Emdrive

  • Q=50,000 (1st gen.) Static thrust=315 mN/kW Specific thrust at 3km/s=200mN/kW
  • Q=6,800,000 (supercond) Static thrust=42.8 N/kW Specific thrust at ??km/s=??N/kW
  • Q=5×10^9 (supercond) Static thrust=31.5 kN/kW Specific thrust at 0.1km/s=8.8N/kW
  • Q=10^11 (supercond) Static thrust=630 kN/kW Specific thrust at 0.1km/s=??N/kW

    • “Q” appears to be the number of reflections within the microwave cavity before the wave is absorbed. So while the static thrust of a high Q cavity is very high it very rapidly loses thrust as speed increases, so much so that to levitate with such a drive seems rather unstable. It would be an incredible thing, if true, but the EM-Drive is yet to be demonstrated in free-fall. That will prove whether it really does convert EM energy directly into kinetic energy. By my rough figuring the first quoted figure above indicates that the EM-Drive is turning EM energy into KE at 60% efficiency at 3 km/s. Not bad.

Carnival of Space #69

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?

Resources of the Solar System: Mercury

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.

Carnival of Space: Week #68 …star-travel won’t be easy

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 😉

Antimatter ain’t what it used to be…

Antimatter annihilation propels the most memorable SF starship of all – the USS Enterprise – between the stars at FTL speeds by powering the manipulation of “subspace”. But what can real matter annihilation do? A naive view would claim an antimatter drive is a photon rocket with an exhaust velocity of lightspeed. The problem with that is that antimatter and matter turn into some seriously nasty gamma-rays. And nothing known can reflect a mega-electron volt gamma-ray. Is antimatter annihilation a hopeless cause then?

Several analyses say otherwise. Robert Frisbee studied the concept a bit more closely for NASA…

Systems-Level Modeling of a Beam-Core Matter-Antimatter Annihilation Propulsion System (Robert H. Frisbee)

ADVANCED PROPULSION FOR THE XXISt CENTURY (Robert H. Frisbee)

HOW TO BUILD AN ANTIMATTER ROCKET FOR INTERSTELLAR MISSIONS

…basically concluding that building the thing was possible, but the performance somewhat poorer than first imagined. So much energy is lost as gamma rays that the effective exhaust velocity he computed was 0.33 c. That’s way, way above the piddling 0.01-0.05 c hoped for from fission or fusion reactions, but a long way from ideal. A major problem was storing the antimatter – very cold anti-hydrogen ice could be levitated due to the residual magnetic field of hydrogen (and anti-hydrogen) molecules, but the storage density had to be very low, maybe 1/10th the density of hydrogen ice (itself just 75 kg/cu.metre.) Another problem was cooling off systems exposed to the gamma-rays produced by the engine. Frisbee’s starship design is very narrow, and very, very long. But he believed a transit speed of 0.25 c was feasible, and allowed a return mission design.

A slightly poorer performance, just 0.2083 c, was derived by Ulrich Walter in his text Astronautics (from Google book preview.) Not bad, but no one is likely to be powering to near lightspeed with any reasonable amount of antimatter. At least with normal matter structures.

Hans Moravec speculated on an interesting material over 20 years ago… Higgsinium …which is composed of heavy, charged supersymmetric versions of the Higgs boson (still undiscovered.) If such could be made in sufficient amounts it could be used as a gamma-ray reflecting material and enable true antimatter/matter photon rockets. However such SUSY particles have yet to be observed – maybe they exist, maybe they don’t. Once the Large Hadron Collider has obliterated enough particles in the TeV range of energies we may well know. Watch this Space for an update in ~2 years.

Nuclear Power Forever

Bernard Cohen studied the renewability of uranium for breeder fast-reactors back in 1983…

Breeder Reactors: A renewable energy source

…concluding that uranium pulled from seawater at 6,500 tons per year was sustainable for 5 billion years. That’s 18.5 TW.yr of raw energy since uranium in a breeder can have virtually 100% of its energy potential liberated. As we humans use about 15 TW.yr from all sources annually that’s pretty good news. He argues that as crustal matter is continually dissolved and carried into the sea the total level in the ocean (over 4 billion tons) will remain much the same for aeons.

Deuterium – a fusion fuel – is available too. Some 44 trillion tons in the ocean. It produces about 300 TJ/kg energy, thus it too could last for aeons at modest power usage levels. Thorium is more plentiful than uranium in the crust, but its solubility is much lower, thus it has to be mined. In the long term, so the crust isn’t overturned for mining, uranium is the fission fuel of choice.