Thomas Lee Elifritz

Chemistry World Article

http://www.nature.com/nchem/journal/vaop/ncurrent/full/nchem.1649.html

RNA with iron(II) as a cofactor catalyses electron transfer, Chiaolong Hsiao, I-Chun Chou, C. Denise Okafor, Jessica C. Bowman, Eric B. O’Neill, Shreyas S. Athavale, Anton S. Petrov, Nicholas V. Hud, Roger M. Wartell, Stephen C. Harvey and Loren Dean Williams, Nature Chemistry, Published Online 16 May 2013

Mg²⁺ is essential for RNA folding and catalysis. However, for the first 1.5 billion years of life on Earth RNA inhabited an anoxic Earth with abundant and benign Fe²⁺. We hypothesize that Fe²⁺ was an RNA cofactor when iron was abundant, and was substantially replaced by Mg²⁺ during a period known as the ‘great oxidation’, brought on by photosynthesis. Here, we demonstrate that reversing this putative metal substitution in an anoxic environment, by removing Mg²⁺ and replacing it with Fe²⁺, expands the catalytic repertoire of RNA. Fe²⁺ can confer on some RNAs a previously uncharacterized ability to catalyse single-electron transfer. We propose that RNA function, in analogy with protein function, can be understood fully only in the context of association with a range of possible metals. The catalysis of electron transfer, requisite for metabolic activity, may have been attenuated in RNA by photosynthesis and the rise of O₂.

It’s alive!

The SLS and the MPCV should be developed in conjunction with the commercial low earth orbit transportation systems. Flying to cis-lunar space to inspect a captured asteroid is an engineering and operations test worthy of a first deep space mission.

Ok, there you have it. One less person whose opinion I will need to consider in the future.

One less thing! That’s gotta be good.

Space Policy Online Article

Good riddance. Rocket design should be left to amateurs.

I’d post a picture but children read this blog.

Ding dong … you know the rest.

Brownsville Texas Cay Sal Bank Duncan Town Ragged Island Inagua Bahamas

Brownsville Texas Cayman Islands Brac Trinidad Tobago

Brownsville Texas to Cay Sal Bahamas, Great Exuma Island and Long Island works for me.

I know a lot of people there, I’ll talk to them and see what they think. Oops, it’s spelled Tobago. Plenty of liquid methane there!

Global Post Article

I hope they think about what they are doing. They’ve got some nice hydrogen engines.

Ok, here’s the deal breaker. Liquid oxygen, propane and methane. I’d have to ship it up from Trinidad and Tobago, and the tanks to hold the fuel are freaking heavy. The tankers themselves and hundreds of millions of dollars, although I read they just demonstrated ship to ship transfer of methane on the high seas in the Gulf of Mexico. I’d need to separate fuel and oxidizer barges, and that right there is looking like millions. If you’re talking a liquid oxygen plant from India then that tens of millions. So unless Elon can land his spaceship with enough residual fuel to make my little test rocket fly from there, I’m screwed. So I’m literally going to have to ship the fuel and oxidizer in all the way from Brownsville, Texas, by rocket, and that’s going to require an import export license. What a mess. I’m glad I won’t have these problems on the moon! I will need molecular junctions or a thermomagnetic refrigerator with thermoelectric precoolers for this.

Sounds like a job for Hugh Mann! Cold beer! Sodas and other exotic fruit drinks!

All imported from the states by rocket. lol.

Outdo that William Mook!

http://arxiv.org/abs/1305.3335

Superconductivity Induced by Breaking Te₂ Dimers of AuTe₂, Kazutaka Kudo, Hiroyuki Ishii, Masaya Takasuga, Keita Iba, Seiya Nakano, Jungeun Kim, Akihiko Fujiwara and Minoru Nohara

Mineral calaverite AuTe₂ is a layered compound with an incommensurately modulated structure. The modulation is characterized by the formation of molecular-like Te₂ dimers. We have found that the breaking of Te₂ dimers that occurs in Au_1-xPt_xTe₂ results in the emergence of superconductivity at T_c = 4.0 K

In this letter, we report that the superconductivity at T_c = 4.0 K emerges upon the platinum doping of AuTe₂. Superconducting Au_1-xPt_xTe₂ crystallizes in a trigonal (distortion-free) CdI₂-type structure, in which Te₂ dimers in AuTe₂ are broken into isolated Te atoms. This result suggests that dimer breaking is responsible for the emergence of superconductivity.

Ok, this is REALLY big.

http://arxiv.org/abs/1305.2778

Fermi Surface Pairing & Coherence in a High T_c Superconductor, Yang He, Yi Yin, M. Zech, Anjan Soumyanarayanan, Ilija Zeljkovic, Michael M. Yee, M. C. Boyer, Kamalesh Chatterjee, W. D. Wise, Takeshi Kondo, T. Takeuchi, H. Ikuta, Peter Mistark, Robert S. Markiewicz, Arun Bansil, Subir Sachdev, E. W. Hudson and Jennifer. E. Hoffman

Superconductivity arises from the pairing of electrons on the Fermi surface. In high temperature cuprate superconductors, evidence compiled from several materials suggests that the Fermi surface expands at a critical doping. However, the nature of the altered Fermi surface, its availability for pairing, and its relationship to the long-mysterious pseudogap phase are unknown. Here we use scanning tunneling microscopy to reveal a quantum phase transition in Fermi surface topology within a single material (Pb_xBi_2-x)La_ySr_2-yCuO_6+z (Bi2201). In lightly doped samples, the Fermi surface terminates at the antiferromagnetic Brillouin zone boundary, but upon increased doping we detect a new Fermi surface component extending to the antinode. We use phase-sensitive quasiparticle interference mapping to prove that d-wave Bogoliubov quasiparticles exist on this recovered antinodal Fermi surface despite the coexisting pseudogap. By magnetic-field-dependent imaging, we finally identify the competitive role of the pseudogap: it inhomogeneously suppresses superconducting phase coherence, while leaving a robust superconducting gap intact. The discovery of these three phenomena within a single cuprate material provides a new basis for understanding the phenomenology of high-T_c superconductivity.

So there you have it, that should clear things up a bit.

http://arxiv.org/abs/1305.2228

Band-structure effects on superconductivity in Hubbard models, Weejee Cho, Ronny Thomale, Srinivas Raghu and Steven A. Kivelson, Submitted to Physical Review B

We study the influence of the band structure on the symmetry and superconducting transition temperature in the (solvable) weak-coupling limit of the repulsive Hubbard model. Among other results we find: 1) As a function of increasing nematicity, starting from the square lattice (zero nematicity) limit where nodal d-wave state is strongly preferred, there is a smooth evolution to the quasi-1D limit, where a striking near-degeneracy is found between a p-wave- and a d-wave-type paired states with accidental nodes on the quasi-one-dimensional Fermi surfaces – a situation which may be relevant to the Bechgaard salts. 2) In a bilayer system, we find a phase transition as a function of increasing bilayer coupling from a d-wave to an s_±-wave state reminiscent of the iron-based superconductors. 3) When an antinodal gap is produced by charge-density-wave order, not only is the pairing scale reduced, but the symmetry of the pairs switches from d_x²-y² to d_xy; in the context of the cuprates, this suggests that were the pseudo-gap entirely due to a competing order, this would likely cause a corresponding symmetry change of the superconducting order (which is not seen in experiment).

So the superconducting condensate spectral weight is derived from the pool of competing charge density weight in a manner that is possibly phase fluctuation induced. Duh. Ok weird.

All is well!

Very important when discussing spacey space geek stuff with nerdy international space cadets.

Would you like some water with your grain alcohol, sir?

Shall I start the propane grill for you?

Or would you like some rum?

Some imported beer?

That’s Bavarian beer, sir.

Cay Sal Bank Bahamas International Spaceport

There won’t be a mosquito left on this place when I get done with it.

Plus, there is a lighthouse silo thing! Many many miles away, but remember, time and space are relative on Cay Sal Bank. I’m going to need a faster sailboat, though. And a smaller spacecraft.

North Elbow Cay Lighthouse

Right now I’m thinking either alcohol and water or propane, or both. In the old days I could get good Haitian tafia rum for fifty cents a gallon out there. We could trade scrap metal or junk.

This is going to be great fun. I will see you here … in the future!

Cay Sal Bank Duncan Town Ragged Island Bahamas

311 miles. 109 degrees.

This is what I have come up with so far for my own personal Bahamian space program.

Extrapolating out from Little Ragged Island, this course takes me right through the channel between Great Inagua and Little Inagua, directly past Little Ambergris Cay in the southern Turks and Caicos and then directly out to sea. 311 miles from launch to booster landing.

I might fly over something called Bush Cay out there, but it misses the birds on Anguilla Cay.

Cay Sal Bank Georgetown Exuma Bahamas

282 miles. 91 degrees.

I can land at Coakley Cay and fly south of Exuma with a single overflight of Long Island.

Boca Chica Brownsville Texas Georgetown Exuma International Spaceport

1150 miles. 92 degrees.

Now I’m finding out the SSME is extremely sensitive to acceleration and propellant pressure head, so screw that. Next! So just how far can an advanced new modern booster fly with an efficient and lightweight methane fueled closed cycle combustion engine? Nobody is going to want to hang around Cay Sal when they could hang around in Exuma or the Cayman Islands, right? That’s going to be one hot booster. Overflight over north Florida seems like a better bet, then he can drop them anywhere along the Gulf coast. But heck, I just want to be prepared!

The 21st century comes to the Bahamas.

Cape Canaveral Air Force Station Florida Walkers Cay Bahamas

160 miles., 122 degrees.

Spaceports. Jobs.

Update : On the other hand I could LAUNCH from Cay Sal with a mobile launch platform and then land at Duncan Town and then sneak through past Little Inagua and the Turks and Caicos!

Yay!

Space Cadets

Bring it on, Chuck.

Archimedes Cube Docking Port Node

So this is the next crackpot space cadet idea to dramatically reduce the cost of space station design and construction – a simple extrapolation of the cable stabilized Archimedes Cylinder Sphere to three dimensions. As you can clearly see there isn’t much fabric involved. In fact, there is so little fabric, that the vertices for all practical purposes could easily be solid metal. But that would not be useful in reusing the Archimedes Sphere components into the docking nodes and ports. The thing would have to be launched pressurized and inflated of course, filled with cargo. And all manner of solar panels, radiators, robotic arms and cameras could be attached to all of the eight vertices. So with the upper stage with its enclosed spherical habitat, and the Dragon capsule and its service module, the new mini space station design is now complete.

Geometrically speaking, if you round off the vertices, I’m not exactly sure what you would call this, so I call it the Archimedes spheroid. Or cuboid. In valley speak it’s totally tubular. Not quite up to standards of practice as Elon Musk’s famous 3 by 3 to circular octagonal transformation, but it will have to do for now. Spherical cuboids with multiple graboids for gnarly space stations!

Cay Sal Bahamas International Spaceport

I heard from a little bird that new methane powered SpaceX launch vehicles will be so powerful and efficient with cross feeding that the center stage will overfly Florida. At the very least they are going to need some overflight permission for the upper stages, even with a slight dogleg. I have already identified Walker’s Cay in the Grand Cay district of the northern Bahamas as a viable space port for Kennedy Space Center and Cape Canaveral launches, assuming no cross feeding for the boosters, so the next step is to find Mr. Musk a vacation destination with no email or internet services, something easily accessible by spacecraft, preferably a reusable methane powered launch vehicle booster. Since he will need overflight permission from the Bahamas anyways, then Cay Sal Bank it is. Nobody except the already decimated populations of rare ground nesting birds will complain of stratospheric rocket over flights either. So Anguilla Cay is out because of the birds, but Cay Sal is a barren wasteland already overrun by Cuban refugees.

The next stop after Cay Sal Bank would be South Andros Island if his crossfeeding methane fueled boosters are that powerful and efficient, and the next stop after South Andros is … get this … Lansing Cay and Rudder Cut Cay! And I have no internet service! Not that I can’t get it, though, the Farmer’s Cay telephone tower is only five miles away. I’m assuming that he’ll have his own personal packet relay internet email satellite by then anyways.

Possibly his own planet too. And his own bank, of course.

So, if Elon needs a vacation, I can suggest he skip the 405 and take the Bill and Ted directly to the beach, and if that works out for him he can fly his rocket over to the new Rudder Cut Cay Rocket Center and vacation with my family on Lansing Cay for free. I suggest he bring food.

And a toothbrush. For a more excellent adventure.

Lansing Cay Exuma Bahamas

Update : There is also Boca Chica Airfield at the Naval Air Station in the Florida Keys. Ironic.

Update 2 : There is also Ragged Island and the Jumentos, and Flamingo Cay is FOR SALE!

I can’t believe how quickly and decisively I solved Elon’s launch vehicle booster landing problem.

View Larger Map

X marks the Space.

http://www.privateislandsonline.com/islands/flamingo-cay

And of course, this post wouldn’t be complete without this :

Captain C – Exuma Hunter – Farmer’s Cay – Exuma

Update 3 – Coakley Cay! Plus there are two airstrips over on the Great Exuma mainland if we can land them horizontally in the future. But then we could launch and land anywhere! Wait, with overflight, we can already do that. Gosh, and I was having so much fun with this exercise.

I can’t believe it took me this freakin long to figure this out. Elon must be laughing his ass off.

Update 4 : The Cayman Islands look pretty good too, he could sneak past the Yucatan and make it all the way to Aruba Grenada Trinidad and Tobago and the open ocean.

Update 5 : Cay Sal is going to be the site of my awesome Bahamian spaceport regardless.

What goes up, must come down!

I’m good.

Tunguska Meteorite Meteoroid Meteor Frangments

Discovery of probably Tunguska meteorites at the bottom of Khushmo river’s shoal, Andrei E. Zlobin

The author describes some stones which he found at the bottom of Khushmo River’s shoal during 1988 expedition into the region of the Tunguska impact (1908). Photos of stones are presented. Three stones have traces of melting and the author consider these stones as probable Tunguska meteorites. Some arguments are presented to confirm author’s opinion. Results of investigation of prospect holes in peat-bogs are briefly described too. New data concerning heat impulse of the Tunguska impact are obtained. There is the assumption that some meteorites which are formed during comet impact looks like stony or glass-like thin plates with traces of melting.

Live Science Article

http://arxiv.org/abs/1304.7900

Superconductivity induced by hydrogen anion substitution in 1111-type iron arsenides, Hideo Hosono and Satoru Matsuishi

Hydrogen is the simplest bipolar element and its valence state can be controlled from +1 to -1. We synthesized the 1111-type CaFeAsH and LnFeAsO_1-xH_x (Ln = lanthanide) with the ZrCuSiAs type structure by a high-pressure synthesis method. The position and valence state of the substituted H were determined by neutron diffraction and density functional theory calculations. The close similarity in the structural and electrical properties of CaFeAsH and CaFeAsF indicated the formation of the hydride ion (H^-), which is isovalent with the fluoride ion (F^-), in the 1111-type iron arsenides. When some of the O^2- ions in LnFeAsO are replaced by H^-, superconductivity is induced by electron doping to the FeAs-layer to maintain charge neutrality. Since the substitution limit of hydrogen in LnFeAsO (x~0.5) is much higher than that of fluorine (x~0.2), the hydrogen substitution technique provides an effective pathway for high-density electron-doping, making it possible to draw the complete electronic phase diagram of LnFeAsO. The x-T diagrams of LnFeAsO_1-xH_x (Ln = La, Ce, Sm, Gd) have a wide superconducting (SC) region spanning the range x = 0.04 to 0.4, which is far from the parent antiferromagnetic region near x = 0.0. For Ln=La, another SC dome region was found in the range x = ~ 0.2 to ~0.5 with a maximum T_c = 36 K, in addition to a conventional SC dome located at x ~0.08 with maximum T_c = 29 K. Density functional theory calculations performed for LaFeAsO_1-xH_x indicated that the newly observed T_c is correlated with the appearance of degeneration of the Fe 3d bands (dxy, dyz and dzx), which is caused not only by regularization of the tetrahedral shape of FeAs₄ due to chemical pressure effects but also by selective band occupation with doped electrons. In this article, we review the recent progress of superconductivity in iron (oxy)arsenides and related compounds induced by hydrogen substitution.

Super cool stuff.

http://arxiv.org/abs/1305.0006

Un-Fermi Liquids: Unparticles in Strongly Correlated Electron Matter, Philip W. Phillips, Brandon W. Langley, Jimmy A. Hutasoit

Since any non-trivial infrared dynamics in strongly correlated electron matter must be controlled by a critical fixed point, we argue that the form of the single-particle propagator can be deduced simply by imposing scale invariance. As a consequence, the unparticle picture proposed by Georgi is the natural candidate to describe such dynamics. Unparticle stuff is scale-invariant matter with no particular mass. Scale invariance dictates that the propagator has an algebraic form which can admit zeros and hence is a candidate to explain the ubiquitous pseudogap state of the cuprates. The non-perturbative electronic state formed out of unparticles we refer to as an un-Fermi liquid. We show that the underlying action of the continuous mass formulation of unparticles can be recast exactly as an action in anti de Sitter space. We find that this mapping fixes the scaling dimension of the unparticle to be d_U=d/2+sqrt(d²+4)/2 and ensures that the corresponding propagator has zeros with d the spacetime dimension of the unparticle field. Should d=2+1, unparticles acquire the non-trivial phase 2π d_U upon interchange. Because d_U is non-integer and in general not half-integer, clockwise and counterclockwise interchange of unparticles do not lead to the same phase and time reversal symmetry is broken spontaneously as reported in numerous experiments in the pseudogap phase of the cuprates. The possible relevance of this mechanism to such experiments is discussed. We then formulate the analogous BCS gap using unparticles and find that in contrast to the Fermi liquid case, the transition temperature increases as the attractive interaction strength decreases, indicating that unparticles are highly susceptible to a superconducting instability.

Unparticle Unphysics.

It’s the next big thing.

See also : Howard Georgi (2007). “Another Odd Thing About Unparticle Physics”. Physics Letters B 650 (4): 275–278.

http://arxiv.org/abs/hep-ph/0703260

Howard Georgi

I discuss some simple aspects of the low-energy physics of a nontrivial scale invariant sector of an effective field theory — physics that cannot be described in terms of particles. I argue that it is important to take seriously the possibility that the unparticle stuff described by such a theory might actually exist in our world. I suggest a scenario in which some details of the production of unparticle stuff can be calculated. I find that in the appropriate low energy limit, unparticle stuff with scale dimension d_U looks like a non-integral number d_U of invisible particles. Thus dramatic evidence for a nontrivial scale invariant sector could show up experimentally in missing energy distributions.

http://arxiv.org/abs/1305.0063

Coexistence of the superconducting energy gap and pseudogap above and below the transition temperature of superconducting cuprates, Jeffery L. Tallon, Felix Barber, James G. Storey and John W. Loram, Published as Rapid Communications in Physical Review B

We express the superconducting gap, Δ(T), in terms of thermodynamic functions in both s- and d-wave symmetries. Applying to Bi₂Sr₂CaCu₂O_{8+δ} and Y_{0.8}Ca_{0.2}Ba₂Cu₃O_{7-δ} we find that for all dopings Δ
(T) persists, as a partial gap, high above T_c due to strong superconducting fluctuations. Therefore in general two gaps are present above T_c, the superconducting gap and the pseudogap, effectively reconciling two highly polarized views concerning pseudogap physics.

All is well. ALL IS WELL!

http://arxiv.org/abs/1304.8123

How well do we know the polar hydrogen distribution on the Moon?, L.F.A. Teodoro, V.R.Eke, R.C. Elphic, W.C. Feldman and D.J Lawrence

A detailed comparison is made of results from the Lunar Prospector Neutron Spectrometer (LPNS) and the Lunar Exploration Neutron Detector Collimated Sensors for EpiThermal Neutrons (LEND CSETN). Using the autocorrelation function and power spectrum of the polar count rate maps produced by these experiments, it is shown that the LEND CSETN has a footprint that is at least as big as would be expected for an omni-directional detector at an orbital altitude of 50 km. The collimated flux into the field of view of the collimator is negligible. Arguments put forward asserting otherwise are considered and found wanting for various reasons. The maps of lunar polar hydrogen with the highest contrast, i.e.sspatial resolution, are those resulting from pixon image reconstructions of the LPNS data. These typically provide weight percentages of water equivalent hydrogen that are accurate to 30% within the polar craters.

Ok, so LEND wasn’t collimated and it looks like we’ll need another neutron spectrometer up there soon. And an imager to take a good close look at the sunlight. Wait. We have LRO.

Maybe we can reprogram it (LRO). Oops, that takes money. No money for the moon!

From this anyone can see that RESOLVE is a good deal.

Neutron spectrometer on a cubesat anyone?

Dicynodon Theraspid

Live Science Article

Weird. Cool!

Weird.

Archimedes Sphere Cylinder Docking Port Hatch Ring Cables

Upper Stage Space Habitats for Near Term Space Tourism and Space Port Operations

Thomas Lee Elifritz, The Tsiolkovsky Group, Madison, Wisconsin USA

Inflatable spherical pressure vessels with twin opposable hatch rings connected by four cables can be preinstalled into the tops of pressurized fuel tanks of the upper stages of conventional launch vehicles, greatly simplifying their design by protecting them from the harsh open space radiation environment. This allows for the on orbit recovery, stabilization and reuse of launch vehicle upper stage spacecraft which would otherwise be discarded to prevent further space debris. Spheres also solve the immediate problem of unloading paying space tourism passengers from the Dragon spacecraft upon reaching orbit, by simply docking with the upper stage port hatch interface, thereby creating an instant space station.

I’ve got a brand new band now too – The Archimedes Group!

Now all I need is a gig.

OSC Antares Launch

Five and a half years. This is like a dream come true.

http://arxiv.org/abs/1304.4869

Superconducting properties of the In substituted Topological Crystalline Insulator, SnTe, G. Balakrishnan, L. Bawden, S. Cavendish and M. R. Lees, To Appear in Physical Review B (Rapid Communications)

We report detailed investigations of the properties of a superconductor obtained by substituting In at the Sn site in the topological crystalline insulator (TCI), SnTe. Transport, magnetization and heat capacity measurements have been performed on crystals of Sn_0.6In_0.4Te, which is shown to be a bulk superconductor with T_c^onset at ~4.70(5) K and T_c^zero at ~3.50(5) K. The upper and lower critical fields are estimated to be μ₀H_c0(0) = 1.42(3) T and μ₀H_c1(0) = 0.90(3) mT respectively, while κ = 56.4(8) indicates this material is a strongly type II superconductor.

Who knew! You could see this coming.

http://arxiv.org/abs/1304.3714

Towards the Minimum Inner Edge Distance of the Habitable Zone, Andras Zsom, Sara Seager and Julien de Wit, Submitted to the Astrophysical Journal

We explore the minimum distance from a host star for an exoplanet to be potentially habitable, in order to maximize future chances of finding other habitable worlds. We find that the inner edge of the Habitable Zone (HZ) for hot desert worlds is at 0.5 AU around a solar-like star (well within the orbit of Venus). The relative humidity is the key controlling factor in determining the inner edge distance because water vapor has a strong impact on the greenhouse warming of the atmosphere, yet too little water vapor will deactivate precipitation and enable CO₂ to accumulate. We estimate that a relative humidity as low as 1% can be sufficient to maintain a liquid water cycle and wash out CO₂ from the atmosphere. If the surface pressure is too low (~0.1 bar), the water loss timescale of the planet is too short to support life. If the surface pressure is too high (~100 bars), we show using atmospheric circulation arguments, that the day-night side temperature difference on slow rotators and tidally locked planets is too small to enable an active water cycle. In contrast, the temperature difference on fast rotators with high surface pressure can be large enough to produce rain. Intermediate surface pressures (~1-10 bars) can provide suitable conditions for a water cycle independent of the planetary rotation period. We additionally find that the water loss timescale is influenced by the atmospheric CO₂ level, because it indirectly influences the stratospheric water mixing ratio. If the CO₂ mixing ratio of dry planets is smaller than 10^-4, the water loss timescale is ~1 billion years, which may be too short for complex life to evolve.

http://www.nature.com/ncomms/journal/v4/n4/abs/ncomms2686.html

Ocean lead at the termination of the Younger Dryas cold spell, Christof Pearce, Marit-Solveig Seidenkrantz, Antoon Kuijpers, Guillaume Massé, Njáll F. Reynisson and Søren M. Kristiansen, Nature Communications, 4, 1664, 9 April 2013

The Younger Dryas (YD) cold interval is one of the most abrupt climate events of Earth’s recent history. The origin of this rapid, severe cooling episode is still widely debated, but it was probably triggered by a large freshwater influx to the North Atlantic resulting in disruption of the Atlantic Meridional Overturning Circulation. The YD termination, despite having been even more abrupt than the onset has, however, received significantly less attention. Here using multi-proxy data from a high-resolution marine sediment record, we present evidence for a gradual decrease of the Labrador Current influence, northward migration of the Gulf Stream oceanic front and a rapid decline of sea-ice cover at the YD termination. Our data indicate a stepwise sequence of events with changes in ocean circulation clearly preceding those in atmospheric conditions, in contrast to the hitherto commonly assumed single-event rapid climatic shift at the YD–Holocene transition.

Oh knowz! Tell me it isn’t so!

The mini inverse Younger Dryas effect.

No Moon for NASA. He just gave the moon away to private industry, for free!

Hooray for Charlie! I love Charlie Bolden. The Asteroid Initiative. I’m praying for Charlie.

Now back to this moon landing thing. Ring. Here is our latest crackpot space cadet idea. A ring of 1000 lbf thrusters around the rim of the intertank segment, 48 of them, every couple of feet. Transition form center J-2X thrust just above lunar polar surface touchdown to the upper pulsed ring of fire, and land, very carefully. Fuel and oxidizer can be stored in tanks above and below the plane of the intertank, inside the intertank. There are issues with this, but it looks interesting. At the very least it solves the digging a huge hole in the lunar regolith and creating an exhaust plume ejecta blanket so violent and energetic that it propels dust into lunar orbit … problem.

Maybe I’ll patent it! At the least I’m going to publish it. Hey … I just did!

I’m sorry about the Mars thing, Charlie, I feel your pain.

Update : Bringing a spacecraft do a dead stop on an imaginary plane ten meters above the surface of the moon with a weakly throttleable engine running at several lunar gees, and then transitioning to a ring cluster of landing engines running at slightly above unity vehicle thrust to weight ratio, is going to bring an entirely new, more dramatic meaning to ‘sticking the landing’.

Update 2 : You could put four super-Dracos on a tower on top as well, like a landing abort system. On the moon eight super Dracos would easily do it too. Angled out from the intertank.

Update 3 : Now I just need to package this into something small enough to afford. Like a tall cylindrical lander with small wheels. A mobile ISRU unit with a habitat. Totally space cadet.

Update 4 : Come to think of it I could easily build a flying testbed with the single super Draco and tens of Dracos, a Draco Grasshopper. That would easily validate the concept. It’s mostly fuel anyways. We’re gonna need a new fuel, though. This is something you’re gonna want to stay far away from in testing, and you’ll have to burn off all the extra fuel. Yuk. Makes for a really bad day someday too. Ok, we can do this in isopropyl alcohol. Or better yet, ethanol!

Pure grain alcohol. On the moon! The Rooskies are gonna want in.

Update 5 : A SpaceX Lunar Dracohopper – lander, hopper, rover. That’s the best I can do on short notice. It solves the problem of having separate engines, separate fuel, attitude control, fuel settling, fuel freezing and boiling, vehicle thermal management, etc, and I can launch it on a SpaceX launch vehicle. It’s going to be super expensive, but what the heck.

Even the moon is a bridge too far it seems.

http://webpages.charter.net/tsiolkovsky/Moon_Base.pdf

Planck Cosmic Microwave Background Radiation Universe Map

Don’t get sucked into the hallucination!

http://arxiv.org/abs/1112.0737

http://www.pnas.org/content/110/12/4539.abstract

Coupling of a high-energy excitation to superconducting quasiparticles in a cuprate from coherent charge fluctuation spectroscopy, Barbara. Mansart, José. Lorenzana, Andreas. Mann, Ahmad. Odeh, Mariateresa. Scarongella, Majed. Chergui and Fabrizio Carbone, Proceedings of the National Academy of Sciences of the United States of America, PNAS, Vol. 110, No. 12, Pages 4539–4544

Dynamical information on spin degrees of freedom of proteins or solids can be obtained by NMR and electron spin resonance. A technique with similar versatility for charge degrees of freedom and their ultrafast correlations could move the understanding of systems like unconventional superconductors forward. By perturbing the superconducting state in a high-T_c cuprate, using a femtosecond laser pulse, we generate coherent oscillations of the Cooper pair condensate that can be described by an NMR/electron spin resonance formalism. The oscillations are detected by transient broad-band reflectivity and are found to resonate at the typical scale of Mott physics (2.6 eV), suggesting the existence of a nonretarded contribution to the pairing interaction, as in unconventional (non-Migdal–Eliashberg) theories.

I blogged this in an earlier version of this blog (The Blob) but it’s nice to finally see it in print.

I suspect it will be soundly ignored by workers in the delusional high T_c superconductivity field.

I cover this because, while the vast bulk of work in this field is utter trash – this is the real deal.

It’s even got some press, finally. I don’t see how they can ignore this phenomenon anymore.

http://phys.org/news/2013-04-high-temperature-superconductivity.html

http://arxiv.org/abs/1304.0505

Broken relationship between superconducting pairing interaction and electronic dispersion kinks in LSCO, S. R. Park, Y. Cao, Q. Wang, M. Fujita, K. Yamada, S.-K. Mo, D. S. Dessau and D. Reznik

Electronic band dispersions in copper oxide superconductors have kinks around 70 meV that are typically attributed to coupling of electrons to a bosonic mode. We performed angle resolved photoemission spectroscopy (ARPES) experiments on overdoped cuprate high temperature superconductors to test the relationship between the superconducting transition temperature and electron-bosonic mode coupling. Remarkably, the kinks remain strong in the heavily overdoped region of the doping phase diagram of LSCO, even when the superconductivity completely disappears. This unexpected observation is incompatible with the conventional picture of superconductivity mediated by the sharp bosonic modes that are responsible for the kink. Therefore, the pairing likely originates from something else, such as from interactions with a very broad electronic spectrum or from an unconventional mechanism without pairing glue.

Ouch. That’s gotta hurt.

UFO Alien Spaceship Crash Planet Earth

http://arxiv.org/abs/1303.7433

Unidentified Moving Objects in Next Generation Time Domain Surveys, James R. A. Davenport, Accepted for Publication in the Journal of Speculative Astronomy

Existing and future wide-field photometric surveys will produce a time-lapse movie of the sky that will revolutionize our census of variable and moving astronomical and atmospheric phenomena. As with any revolution in scientific measurement capability, this new species of data will also present us with results that are sure to surprise and confound our understanding of the cosmos. While we cannot predict the unknown yields of such endeavors, it is a beneficial exercise to explore certain parameter spaces using reasonable assumptions for rates and observability. To this end I present a simple parameterized model of the detectability of unidentified flying objects (UFOs) with the Large Synoptic Survey Telescope (LSST). I also demonstrate that the LSST is well suited to place the first systematic constraints on the rate of UFO and extraterrestrial visits to our world.

Yeah. Ok. But what about this mess in my yard?

Northwest Africa NWA 7325 Green Meteorite From Planet Mercury

http://www.lpi.usra.edu/meetings/lpsc2013/pdf/2164.pdf

Space.com Article

Update : This meteorite may be too old to be from Mercury. Some other planetoid I guess.

Phase Diagram – 1T-TaS_2-x_Se_x – Superconductivity

http://arxiv.org/abs/1303.6715

New Superconductivity in Layered 1T-TaS_2-xSe_x Single Crystals Fabricated by Chemical Vapor Transport, Yu Liu, Ran Ang, Wenjian Lu, Wenhai Song, Lijun Li and Yuping Sun

Layered transition-metal dichalcogenides 1T-TaS_2-xSe_x (0<=x<=2) single crystals have been successfully fabricated by using a chemical vapor transport technique in which Ta locates in octahedral coordination with S and Se atoms. This is the first superconducting example by the substitution of S site, which violates an initial rule based on the fact that superconductivity merely emerges in 1T-TaS₂ by applying the high pressure or substitution of Ta site. We demonstrate the appearance of a series of electronic states in 1T-TaS_2-xSe_x with Se content. Namely, the Mott phase melts into a nearly commensurate charge-density-wave (NCCDW) phase, superconductivity in a wide x range develops within the NCCDW state, and finally commensurate charge-density-wave (CCDW) phase reproduces for heavy Se content. The present results reveal that superconductivity is only characterized by robust Ta 5d band, demonstrating the universal nature in 1T-TaS₂ systems that superconductivity and NCCDW phase coexist in the real space.

This is cool. Really cool.

Dare I say … Se xy!

JPL Press Release