Wild bush fire-climate links

The current frenzy of linking bush fires in Australia to climate change epitomises climate change hysteria. 
 

Australian Green MP Adam Bandt was quick to hype the link and even accused Abbott of putting on a fire uniform for a stunt, despite Abbott's longstanding service to the volunteer fire brigade.
 

Sky News Australia has also given air time to Tim Flannery's axed Climate Council (which annoys me).  Sky News tends to favour AGW despite conspiracy theories that any media outlet Rupert Murdoch owns is biased against it. (I believe Murdoch owns half of Foxtel, maker of Sky News Australia.)

Trenberth's missing heat still missing

In its latest report the IPCC has said that the oceans have been warming rather than the sky, in an effort to explain away the problem of the lack of atmospheric warming for 15+ years.  This does solve the problem of what Trenberth called the "missing heat" -- the lack of global warming for (now on) 15 years.

While the missing heat problem is potentially solved by claims of ocean warming, the explanation introduces another problem. If something gets warmer, in this case the ocean, it is less likely to absorb heat, not more; therefore making it less likely that heat from a warm atmosphere would be drawn into the ocean, to be hidden in its deep recesses.

The energy is supposed to come from the atmosphere, specifically its greenhouse layer. If the ocean is getting warmer, the heat should be going outward not inward from it; so, it should be heating the atmosphere, not cooling it!

The IPCC ocean heat model is sensibly based on the idea that heat must move from hot to cold, e.g. that there should be no spontaneous take-up of heat by the oceans.

Trajectory to the moon

1950s era comic depicting the general expectation for space travel -- a space age which never came to pass because of deadly space radiation and other problems that have not yet been overcome

In getting from the ground to space the boosting rocket must provide the energy for lifting the mass, overcoming gravity and air resistance and getting up to orbital speed.  It's a big job that takes a big rocket. Apollo's rocket was one of the biggest, the Saturn V:

It's a biggy: the Saturn V

Space reentry vehicles, part 7

Part 7: Pressure

(index)

At subsonic speed, below Mach 0.3, the pressure of the air coming into the hull of an aircraft is roughly 1/2ρv² where ρ is the density of the fluid medium; for air at sea level = 1.225 kg/m³.  The equation for compressible flow given for above Mach 1 speeds goes as the power of 3.5 rather than 2 and rises much more quickly.

Space reentry vehicles, part 6

Part 6: Control

(index)

After atmospheric reentry the heat shields on the bottom of space reentry capsules have a characteristic burn pattern that starts at a point off centre and emanates to the edge. 

Gemini heat shield after reentry

The central point of the burn pattern is the stagnation point where the air isn't moving parallel with respect to the surface but hits it at right angles.  The temperature and pressure is at a maximum at the stagnation point such as the following diagram depicts:

Space reentry vehicles, part 5

Part 5: More on the detached shock wave

(index)

The term detached shock wave originally referred to an undesirable aerodynamic effect that was found in supersonic projectiles such as bullets.  This type of shock wave was of interest because it had a lot more drag and aerodynamic instability than an attached one.

The first aircraft designed to be supersonic, the Bell X-1, was modelled after the shape of a 0.5 calibre Browning machine gun bullet, which was known to be stable in supersonic flight.

Space reentry vehicles, part 4

Part 4: More on ablation

(index) 

In 1907 American chemist Leo Baekeland invented Bakelite, the world's first plastic.  50 years later it would be chosen as the main ingredient in NASA's reentry capsule heat shields. 

Radio made of Bakelite 

Bakelite was a good choice for spacecraft heat shields because it's a good insulator of heat; it has high strength;  it has an abundance of carbon (a material with a high latent heat); and it has an ability to char rather than melt at high temperature.

Space reentry vehicles, part 3

Part 3: ICBMs and the cold war

(index)

Other than vehicles with a detached shock wave, all aircraft heat up more the faster they move.  From the NASA book Facing the Heat Barrier: A History of Hypersonics [1]: 

At Mach 3 and higher, there was the Lockheed SR-71 that cruised at 85,000 feet. The atmosphere at such altitudes, three times higher than Mount Everest, has a pressure only one-fiftieth of that at sea level. Even so, this airplane experienced aerodynamic heating that brought temperatures above [260C] over most of its surface.

The SR-71 Blackbird gets to 260C over most of its surface.  Aluminium anneals (softens) at 177C (alloys can be higher) making it unsuitable as a material for use on the outside of the Blackbird.  The Blackbird used titanium instead.

Recent ISS spacewalk water leak

Recently, a spacesuit sprung a water leak and the suit started filling with water, such that the astronaut's life was in danger and the "spacewalk" had to be aborted.

As I mentioned in my space reentry vehicle posts (index), if every reentry vehicle of the capsule type (possible exception of the Space Shuttle) is fake, and the only way astronauts can get back to earth is via such capsules, then the International Space Station is fake too*.

One can look through spacewalk footage to find bubbles coming up.  You can also see scuba gear.  Here's another example:

http://www.youtube.com/watch?v=LumFvgrZQXk

Space reentry vehicles, part 1

Part 1: ablation and the detached shock wave

part 2   (index)
 

(Update 3/9/2013: Please note I've updated my view of the detached shock wave since first writing this post.  I now accept that there is a detached shock wave in the sense of a bow shock, but it is not detached in the thermal sense, as claimed by NASA. More in part 5.)

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Most meteoroids burn up almost immediately on entering earth's atmosphere.  The few larger ones that make it to the ground lose 95 - 99% of their mass.  The air around them gets so hot it disassociates to become plasma.  95% of the glowing streak of a meteor is hot air, not hot rock.  According to NASA the temperature of the leading face of ICBMs returning from space is "hotter than the surface of the sun", (5500C+).

Space reentry vehicles, part 2

Part 2: aerodynamics

part 1   (index)

Early on in the design of manned reentry vehicles it was realised that the huge heat and strain of reentry would destroy any protuberances such as wings, rudders etc.  This lead to the minimal design of spheres and cones:

Is space cold? Part 1

part 2

During Apollo 13 an explosion on the way to the moon damaged the service module, causing astronauts James Lovell, Jack Swigert, and Fred Haise to abort what would have been the third landing on the moon.  They came back to earth with the CM LEM and damaged SM.  The SM and LEM were jettisoned shortly before re-entering earth's atmosphere in the CM*.

Is space cold? Part 2

part 1

In part one it was suggested that an object in the sun at distances of earth orbit, or less, will be hot.  What about the case for the shade in space, is it cold? 

Some say that when the Apollo astronauts moved from light to shadow on the surface of the moon, they went from a hot 107C or so to a cold -170C in a matter of seconds.

Neil Armstrong on the surface of the moon during Apollo 11

The porous plate sublimator

Surviving the harsh lunar environment is apparently one of mankind's greatest engineering achievements. 

The space suit worn by the Apollo astronauts on the surface of the moon had to protect them from UV, X, and gamma-rays, heat, and solar flare radiation from the sun; cosmic rays; micro meteors; regulate humidity, carbon dioxide and oxygen; and maintain a pressurised layer of air.

Amazing life-saving suit technology: the state of the art in 1969.  The Apollo 11 suit.