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"chances are that if 700 passengers are flown annually, up to 10 of them might not survive the flight in the first years of the operations." most remarkable also the question who is to blame if a dead and burned space tourist corps comes crashing down from the sky into your car.

This calls for some we serious simulations by the Petkow code it seems to me ...

I still would need some serious input data...

After reading the Hayabusa's story posted by Joris a while ago, I think that the only adequately epic final to conclude this awesome mission is that the capsule will land safely. And empty.

This guy solved a problem many people are trying to solve!!! The optimal control problem for the three body problem (restricted, circular) can be solved using continuation of the secondary gravity parameter and some clever adaptation of the boundary conditions!! His presentation was an eye opener ... making the work of many pretty useless now :)

I like when there are discussions evolving around entries

and on your problem with the RSS Tamas: its the same for me, you get the comments only for entries that you have posted or that you have commented on ...

In order to overcome the communication blackout problem suffered by hypersonic vehicles, a matching approach has been proposed for the first time in this paper. It utilizes a double-positive (DPS) material layer surrounding a hypersonic vehicle antenna to match with the plasma sheath enclosing the vehicle. Or in more easy language, basically one provides an antenna as capacitor, in combination with the plasma sheath (an inductor), they form an electrical circuit which becomes transparent for long wavelength radiation (the communication signal). The reasons is that fluctuations are balanced by the twin system, preventing absorption/reflection of the incoming radiation. Elegant solution, but will only work on long wavelength communication, plus I am not sure whether the antenna needs active control (as the plasma sheath conditions change during the re-entry phase).

I am also looking into this idea since some time and it seems NASA is already ahead, awarding two contract to investigate magnetoshell aerocapture. This could be interesting for probes that want to enter eg Marsian atmospheres at relatively high velocity. Or for multiple re-entry s/c at Earth. The idea of the experiment, The satellite will carry a copper coil, powered by a lithium-ion battery, that generates a magnetic field around the probe. As it descends, the spacecraft will eject a small amount of plasma. This gets trapped in the magnetic field, creating a protective bubble that stops air molecules colliding with the craft and producing heat.

A few years back Mimmo has worked on this, rather from the theory side if I remember well ...

The power requirements for such a thing must be HUGE!

more transformation optics ... 

I still believe that it is worth to check the thermal, mechanical and chemical properties of the developed metamaterials. For hyperbolic re-entries the radiation is still the dominating heat load source and a dominating bandwith may be indentified. A resistive metamaterial should be placed on the nose cap of the entry body in order to reduce local radiation heat load.

Out-of-control Russian space probe may be 'most toxic falling satellite ever: A Russian space probe aiming to land on a Mars moon was stuck circling the Earth after equipment failure Wednesday, and scientists raced to fire up its engines before the whole thing came crashing down.

Is it just me, or is uncontrolled space junk re-entry becoming trendy?

this was a fantastic mission - ... what a pity!

The novel part here is that it can be scaled down to the cubesat platform. I then wondered, could we place multiple of such Cubesats in a 'decaying orbit' around the Sun? Fractionated will give spatial and temporal information which, even with a simple langmuir probe setup, can give information on density, temperature, velocity, ion energy distribution, potential.. Of course they will be lost relatively quickly, but more could be ejected from a mother ship which is orbiting at a safer distance.

For example like the KickSat projec https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space Although a pc-reboot due to a radiation event in the electronics has reset the deployment timeline to approximately 2 days after re-entry... http://www.huffingtonpost.co.uk/2014/05/06/kicksat-satellites_n_5273821.html

Powerful contrast between the two pictures!!

Juxi are you following this one? any idea on its purpose?

Not that I'm an expert in the field in any way, but there are two things I could think of: 1) possibility of bringing the payload back means that it can collect huge amounts of data which wouldn't be possible to be transferred via radio in reasonable time and/or you can bring back data you don't want to be intercepted by enemy 2) I remember reading somewhere that possibility of re-entry from orbit means you can strike any country without violating the airspace of the neighbouring countries. As the project is now managed by military, a purely civil purpose can be safely ruled out in my opinion.

Couldn't find more details on this but sounds interesting.

interesting indeed as a concept and to explore how far one can go to overcome some of the natural deficiencies of wood. regarding the main purpose of debris avoidance, it's typically not the structure that survives re-entry and one would have to see the environmental effect of what would be released in the atmosphere when burning.