sgt_flyer

One of my concerns, is if they send a cubesat near jupiter - will the solar panels provide enough power at these distances to power the various systems ? Heck, the rosetta probe has oversized solar panels to be able to operate so far away from earth (with chemical engines), and still had to get into sleep mode to minimize power usage before reaching jupiter's orbital altitude. Imagine if you need to operate an electric engine near jupiter in order to do your correction manoeuvers / capture burn. The Juno probe (en route to jupiter) also has oversized advanced solar panels. Juno's solar 45m^2 panels could give out 15000w around earth - that will be 428w near jupiter... (Jupiter receive roughly 4% of the sun energy we have here on earth) Cubesats biggest deployable solar panels can currently output 75w - around earth. So the same solar panels would provide less than 1w around jupiter... Cubesats wouldhave big difficulties structurally (and by weight penalty) carrying enough solar panels. (I don't think those cat probes could be really useful past mars... - where solar panels power effectiveness is already cut in half compared to earth)

The earth magnetic field is not strong enough - and not uniform enough to have a serious effect on supraconductors

well, a single bird can cause major damage to a jet engine's compressor blades - even if the blades don't break on the spot, it could very well break inflight - one of these blades going through the jet engine while inflight could kill the engine (especially as most helicopters jet engines are much smaller than airliners turbofans - and on a turbofan, the jet engine part is much smaller than the fan itself - so it reduces the risks of a bird going through the main compressor and combustion chamber) jet engines are tested against bird ingestions (up to a certain size of bird), but taking off after a bird ingestion without checking the engine for damage and cleaning it would be completely stupid. (an helicopter can autorotate to the ground in case of engine failure, but that remains a risky manoeuver - especially if the aircraft has to fly over urban zones - it's best to avoid the risk ).

the risk of cavitation in turbopumps is dreaded by rocket scientists - that's one of the most destructive things you could put on a turbopump. For non reusable engines, that's not a big deal, but SSME's were meant to last for several flights. Basically, cavitation is the formation of a vapour bubble behind the pump's blade (because the pressure is too low) When the bubble grows too large, it collapses, and the liquid hits the back of the blade with a lot of force - enough to damage the lightweight structure & material used in the making of the turbopump. Here's what cavitation can do to a beer bottle. Here's more infos on the process and a damaged turbopump blade image. (And that's an industrial grade blade - heavy & solid ) http://www.processindustryforum.com/article/cavitation-overcoming-cavitation-damage-control-valves-pipelines

They are going to make new thruster tests today starting at 9 a.m. PDT We can follow today's session on their twitter account : https://twitter.com/ISEE3Reboot

"Groundbreaking" projet as they say in the video can't blame them, they began the construction by blowing up the top of the mountain to build the telescope's platform ^^

Well, Airlaunch speeds is even more interesting than the altitude at which they make the launches a turbofan powered aircraft carrier (like whiteknight 2) can easily reach and maintain speeds between mach 0.8 and 0.9 - and do it at the equator. (Near 254m/s of additional speed) - besides, they fly at altitudes way higher than the highest mountains Now, that's still not much compared to orbital speeds

You will face other problems launching from high altitudes for not much gains. Earth's orbital speeds are way higher than KSP's planets - so simply launching from an higher altitude won't change a lot of things. Whereas on eve, the pressure is so strong at sea level that it's very useful to launch from high altitude (so you lose much less delta-v due to drag) Finally, the main problem will be the way higher logistical and infrastructure costs to launch from high altitudes : bridges and tunnels will put severe constraints on your rocket designs (ex : Baikonour cosmodrome : the Proton rocket design was limited by the railroad tunnels.) Whereas they can easily transport huge rocket stages on boat in florida or guyane. (Like the space shuttle's external tank, etc) Basically, i don't think the gains in delta-v you would get by launching at high altitudes would offset the additional costs.

Kourou space center in guyana has a Soyuz launch pad (where the rockets are rolled vertically on the pad from a vertical VAB - instead of the russian style horizontal VAB) - however, they only do unmmaned launches. (using Kourou, allows the soyuz rocket to have a bigger payload for GTO launches with the same rocket - simply because it benefits more from earth's rotation) - and it gives Kourou space center a medium payload capable rocket - Vega for light payloads, Soyuz for medium payloads, and Ariane V for heavy payloads) manned launches to orbit are currently only from baikonour or Jiuquan. (though that may change once russians finish their new cosmodromes)

one of the problems to 'achieve' immortality, is the senescense of cells. basically, in humans, your cells undergo cellular division during all of your life in order to replace dying cells. - however, each division shortens a bit the DNA contained in the cell. once the DNA becomes too short, the cell can't be replaced anymore (and that's not counting all damage cells can get from toxins, radiations, etc we get from all of our lives - and even just plain oxydation (yes, oxygen is also part in what makes us age and kill us in the end ). now, researchers are trying out on lab rats anti senescense techniques - basically, they artifically damaged their cells to create an artificial senescense in the rodent - and managed to cure the effects (the seemingly old rodent were actually rejuvenated when the damage was repaired) - however, it's going to be a very long way to transpose those techniques to humans (so we might see immortal lab rats long before we see immortal humans (will they call the immortal rodent Mr Jingle ? )

Ok, they started their attempt to clear the fuel lines. They are sending infos minute per minute on their twitter account right now, if some people want to follow it https://twitter.com/ISEE3Reboot Edit : it seems they are getting some results (they registered impulses from some thrusters they were trying (not all of them though).

Spacecollege received help from external sources to troubleshoot the probe's fuel systems after their call out for help, and have now a possibility to get it working once again. (Seems they had help from industry experts, and even managed to get in touch with a retired engineer who built similar fuel systems) They are going to try out their new fuel systems tests july 16th. Lets keep our fingers crossed ! http://spacecollege.org/isee3/we-are-borg-crowdsourced-isee-3-engineering-and-the-collective-mind-of-the-internet.html#more

Mmh - regarding any destination beyond mars/phobos - i don't think any cubesat can remain usable at these distances - the cubesats solar panels will not be enough at these distance to power the probe's systems at all (especially if using ion propulsion). (Rosetta has oversized solar panels, and had to go into hibernation when she was too far away) Else , most probes don't need a main engine. They use their RCS nozzles to make their delta-v changes. (Even ion engines are sometimes used to replace chemical monopropellant nozzles)

here's my own stock mini saturn V recreation here's the thread for more informations http://forum.kerbalspaceprogram.com/threads/77335-023-5-mini-Saturn-V-with-Launch-Umbilical-Tower

Well, if i understood what they are currently searching - it would seems isee-3 uses bladerless hydrazine tanks, and use the probe's spin to separate the hydrazine from the nitrogen. (Basically, the heavier hydrazine fall 'outwards' where the valves are located, and the lighter pressurant remains inwards. (Due to centrifugal forces) Spacecollege has asked people for a crowdsourced resaerch effort on the dissolving rate of Nitrogen in hydrazine (basically, one of the leads they are following is that the nitrogen would have dissolved in the hydrazine over the years - so the nitrogen is still here, but can't apply any pressure, because it's everywhere in the hydrazine. If the problem is because of the dissolving , maybe they'll find a way to separate the hydrazine from nitrogen (on earth, we can use heat to extract the gazes trapped in a liquid for example)

Mmh - NTR's exhausts is way hotter than 1000°C - KIWi-1 exhaust ran at 2683°K. LH2-lox exhausts generally runs near 3000°K - SSME's even ran at higher temps. What gives NTRs a better ISP than chemical, is that it don't use oxydizers. As for the comparison between a nuclear thermal reactor and a nuclear thermal rocket, lies in the fact that the rocket's reactor is 'transferring' it's heat to the reaction mass - which is ejected out of the rocket, so it's relatively easy to keep it under control, whereas we work with closed loops on surface reactors - which could cause a runaway reaction if not cooled correctly. Heck - current reactor's fuel are not let to heat more than 600°C in the fuel rods themselves (or else you 'll damage the rods) - NTR's fuelrods are different than standard reactor fuel rods (and much higher in price too ) The concept behind your idea is neat - but i don't think it can match even chemical ISPs. Heck, even a turbojet's combustion chamber runs hotter - to the point the exhaust is cooled down by air from intakes before it runs through the driving turbine.

don't forget you'll need at one point (if you're going with liquid fuels) to drive your turbopumps (for both cooling and engine feeding). the current way to drive turbopumps remains using a gas generator + turbine, which will eat some of your ISP / and add a bit of weight to your system.

Angara 1.2 first launch from Plestek, which was to happen today, friday 27th has been postponed 24 hours for technical reasons. new launch date : 11h15 UTC june 28th. (7h15 AM EDT) http://www.nasaspaceflight.com/2014/06/russias-angara-rocket-maiden-flight/ http://forum.nasaspaceflight.com/index.php?topic=34292.75 Angara's first launch is only a suborbital test launch - it won't put anything into orbit. the configuration to be launched is a angara 1.2 : 1 URM1, and 1URM2(angara's block I) above it. edit : one of the informations would be that a leaky valve was the origin of the launch scrub. http://www.russianspaceweb.com/angara1pp.html Edit 2 : it seems that the angara launch might not occur before quite some time. (They may need to roll the rocket back to the assembly building and make the repairs.)

Besides even if it was possible to transmit infos by breaking the entaglement - you'll have a problem : how will you reestablish entanglement afterwards ? so your entangled pairs would be a 1 use thing - not really useful for data links.

@Tiberion mmh - after rereading Russianspaceweb article - (specifically http://www.russianspaceweb.com/angara1_pp_preflight.html) the angara's A1.2 was originally stated for a may 2014 launch - the december launch date was meant for the angara A5 version (so, let's wait & see )

Liquid fuel boosters for the SLS is already something being researched on, for future SLS upgrades. Among the contestants for advanced boosters design for SLS block II, P&W, Rocketdyne and dynetics have associated to revive Saturn V F-1 engine, to create the Pyrios booster - a Kerolox booster, each booster propelled by two of their F-1B engines, - the ISP advantage the pyrios would have over other planned Block II SRB would allow SLS to lift 20 more tons than it's competitors. KSP LFB KR1x2 is modelled after the pyrios booster concept art. (Besides, one of the other advantages of LFB would be to lower drastically the weight the Crawler would have to transport to the pad - they would be fueled only one in position, whereas the SRB's are full before getting out of the VAB.) - for an idea,in prevision for the various SLS configurations they had to increase the crawler's lifting weight from 5400 metric tons to 8200 metric tons.

Grid fins are used a lot when you need to fold fins to limit the shape size. A lot of russian stuff use grid fins, including some real rockets - the N-1 rocket had huge grid fins, and current manned soyuz have grid fins mounted on the fairing - they are deployed in case of abort. UR-700 and UR-900 concepts made use of grid fins too One other advantage of grid fins is the low torque needed to control them - allows for much smaller servos than standard steerable fins. The downside being the increased complexity - as you need to include a reliable way to deploy them

Hehe fluorine is really nasty stuff, very difficult to store. (Most storage capabilities occurs when the metal container forms an fluorine oxid layer - if you scratch that layer, chances are that the oxid layer won't reform fast enough... One of the fluorine compounds, CiF3 is hypergolic with a lot of things - including, concrete, gravel and even glass and sand ! (A 900kg CiF3 industrial spill once burned through 30cm of concrete and 90cm of gravel underneath). add to that the price of the lithium (as it's used in batteries and solar panels)

The LEMs hypergolic tanks were too big for easy bladder integration. (Bladders don't scale well) - the Lem's RCS monopropellant used a bladder system - basically, the bladders were only useful to them from a 0g start for the RCS. They then used those RCS to provide enough ullage to use the non bladder tanks.