Japan Successfully Launches Solid Fuel Rocket (oann.com)

randomErr writes: Japan successfully launched a solid fuel rocket named Epsilon-2. The 26-meter-long rocket launched from the Uchinoura Space Center at about 8 p.m. local time. Japan Aerospace Exploration Agency (JAXA) said this is the latest in Tokyo's effort to stay competitive in an industry that has robust growth potential and strong security implications. Also, this is to curb costs for rocket launches. The Epsilon-2 three-stage rocket [is part of a new generation of solid propellant rockets that aim] to put communication and weather satellites in space.

Comments

Slightly better summary

[ChoGGi]

https://www.nasaspaceflight.co...

Re:Slightly better summary

[jandersen]

Not to belittle their achievement, but it has to be said (with a tongue in the eye/twinkle in cheek): China achieved this already in the 7th century!

Re:Slightly better summary

[K. S. Kyosuke]

China was studying Earth’s magnetosphere from orbit in the 7th century? ;)

Re:Slightly better summary

[Cytotoxic]

Lots more info over at Spaceflightnow.com

Re:Slightly better summary

[Bongo]

Yes, and time travel in the 22nd century.

Re:Slightly better summary

[Anonymous Coward]

The only thing China will be 'studying' in the 22nd century will be the same things they study right now: Better, more efficient ways to oppress human beings and maintain their hold on power. That is, of course, unless the rest of the world, and the Chinese people, get tired of the Communist Party bullshit, and kick their red asses out once and for all. Power to the People!

Title is wildly misleading

[TimothyHollins]

Why on Earth anyone would make a rocket out of solid fuel is beyond me. It seems unnecessarily hazardous and I don't understand the benefits. Are they gonna sell it to the Russians for giggles?

Re:Title is wildly misleading

[dbIII]

It's all there in the summary that you probably should have read before posting so that you don't waste our time.

Re:Title is wildly misleading

[Anonymous Coward]

Much of the cost of a liquid fuel rocket is an engine, here you just have a simple pipe open on one end.

Re:Title is wildly misleading

[thechemic]

It would seem that technology enthusiasts who have an interest in information systems don't have a strong desire to read about rockets posted on a website that used to be dedicated to news about information systems.

Re:Title is wildly misleading

[TimothyHollins]

It's all there in the summary that you probably should have read before posting so that you don't waste our time.

Thank you for noticing me, supreme arbiter of the Internet.

You should probably change the word 'our' to 'my' since have it on good authority that other people actually enjoy laughter.
On a related note, does it bother you that the Funny mod is +1 and not -1?

Re:Title is wildly misleading

[Anonymous Coward]

You need to remember that you sometimes need to blatantly point out humour to some people... (probably related to people believe fake news sites).

Something like
"Why on Earth anyone would make a rocket out of solid fuel is beyond me!!!??!!"

Then, if you're lucky, they _might_ get it...

!!!??!!

Re:Title is wildly misleading

[Anonymous Coward]

This is news for nerds. Any "nerd" who doesn't think rocketry is awesome should probably turn in their badge on the way out.

Re:Title is wildly misleading

[Hognoxious]

Usually you have to fill liquid fuelled ones up just before you launch them. This means if anyone is observing you, they know in advance that you're going to launch.

This can be a disadvantage for certain applic@.m,mk
no carrier

Re:Title is wildly misleading

[K. S. Kyosuke]

It is, but the fuel on the other hand is very cheap, whereas solid propellants can be much more expensive to process, especially for very big rockets. Anyway, building SRBs is more or less a side effect of having missile-equipped military. You don't look at costs at that point.

Re:Title is wildly misleading

[hey!]

US ICBMs are solid fuel rockets. This is so they can be launched quickly before an attack by an adversary can take them out.

That said the primary design goal for this particular rocket is low cost. One of these particular rockets costs only $38 million. Many launch systems aimed at putting about 1000 kg into orbit are solid fuel because it's relatively cheap to build and operate a solid-propellant rocket and you don't need to squeeze every last bit of specific impulse out of the rocket to launch a modest payload.
.

Re:Title is wildly misleading

[Anonymous Coward]

This is news for nerds. Any "nerd" who doesn't think rocketry is awesome should probably turn in their badge on the way out.

I think Rockety is awesome when it's done by NASA and not con-artists that cut corners with safety to make a buck.

Re:Title is wildly misleading

[Anonymous Coward]

I'm not sure the entire accuracy of this information because it's difficult to tell if the sources are talking about the Epsilon or Epsilon-2, but it sounds like it's just a solid "booster" for the lower stage. The upper stages are still liquid for more control.

Re:Title is wildly misleading

[MrLogic17]

As commented above, the article at:
http://spaceflightnow.com/2016...

notes that all 3 stages are solid propellant systems.I see no mention of liquid propellants, though there may be some for the spin-up and station keeping.

If this really is a completely solid propellant system, the cost savings would be incredible. One number I saw was 1/3 the cost of traditional systems. At least for earth orbit, that should give the Space-X crew some competition for a while - which is good for everyone.

Re:Title is wildly misleading

[Anonymous Coward]

There are no benefits. These are still getting built because the space nutter's religion says we need to move stuff off of "this rock." All that does is subsidize companies making rockets and satellites, which are completely useless with modern technology. But nerds can't grow up from the comic books and tv shows they watched as a kid to realize space is useless.

Re:Title is wildly misleading

[Ol Olsoc]

Why on Earth anyone would make a rocket out of solid fuel is beyond me. It seems unnecessarily hazardous and I don't understand the benefits. Are they gonna sell it to the Russians for giggles?

Solid fuel is more stable.

You don't have to fuel right before launch, lose a lot of the fuel and Oxidizer during the runup to launch, and then have to pump it back out if the launch is scrubbed.

It's really handy for first stage boosters. If you want a lot of boost, a rocket like the Saturn V has to have incredible amount of thrust just to get off the ground. Strap on a couple solid boosters and suddenly you can save the liquid fuel for later in the flight when the throttleability that solid fuel lacks is more needed for precise orbit injection.

Re:Title is wildly misleading

[Ol Olsoc]

It would seem that technology enthusiasts who have an interest in information systems don't have a strong desire to read about rockets posted on a website that used to be dedicated to news about information systems.

If you look at the top of the page, there are many things that Slashdot is about. Technology is one of them.

And this is technology, and this is of direct interest to many of us - myself included.

I mean it isn't the level of interest of Vim vs emacs arguments always bring us, or the ever enjoyable password arguments, but some of us have a passing interest in rocketry.

Re:Title is wildly misleading

[Ol Olsoc]

It is, but the fuel on the other hand is very cheap, whereas solid propellants can be much more expensive to process, especially for very big rockets. Anyway, building SRBs is more or less a side effect of having missile-equipped military. You don't look at costs at that point.

There is some pretty solid science and technical reasons why a strap-on SRB is a more cost efficient way to go than designing and running a liquid fueled rocket capable of running the whole mission.

Especially that first few thousand feet.

Do you have any references to solid fuel boosters being more expensive to process than the compression and storage and pumping and evacuation if needed of the liquid fuels? I assume that you are speaking only of hydrogen/oxygen fuel, not the hypergolics or highly refined kerosene fuels.

Re:Title is wildly misleading

[gman003]

Solid rocket motors have tradeoffs. In some circumstances, they make sense.

They are long-term storage-stable. Build it, stick it in a silo somewhere, and leave it be for a few years, it will still launch just fine. Hypergolic liquid-fueled rockets can't be kept ready-to-launch for more than a few days*, and cryogenic liquid-fueled rockets can't be kept ready-to-launch for more than a few hours. This makes them particularly preferable for military uses, everything from little anti-tank rockets to ICBMs. This also reduces the number of ground crew needed - you don't need to worry about fueling, just electricals and signals.

They have extremely high levels of thrust, due to the extremely high energy density. The Shuttle's SRBs were each twice as powerful as the largest liquid-fueled rockets. This makes them very popular as boosters.

They have a lot of impulse per unit volume. What most rockets care about is impulse per unit mass (aka specific impulse), but some cases care about volume. If you're launching from an aircraft, like Stratolaunch or Pegasus, this matters. If you have constrained volume because you're in a fixed-size fairing, this matters. If you're launching from a submarine, this matters.

It's also often a matter of economies of scale. Countries with military missile programs (which have many reasons to go solid-fueled) often use them for other things as well, either to subsidize their military-industrial complex or to take advantage of existing scale to make civilian rocketry cheaper, depending on how cynical you are. The US, masters of solid-fueled ICBMs, used a pair of massive SRBs on the Space Shuttle, and will use them again on SLS, if that ever flies. The ESA's Ariane 5 uses SRBs based on a French SLBM. Japan may not field ICBMs, but they too have a reason - the first stage of this rocket is almost identical to the booster of their H-II rocket.

The higher stages are solid-fueled presumably to maintain that low-ground-crew capability, and the minor reduction in drag can't hurt either.

Re:Title is wildly misleading

[Waffle Iron]

I think Rockety is awesome when it's done by NASA and not con-artists that cut corners with safety to make a buck.

So you prefer rocketry in the form of a Rube Goldberg contraption that's so unwieldy that safety corners have to be cut in order to make any attempt at a launch.

Re:Title is wildly misleading

[budgenator]

Cheaper, they have less parts and don't have all of the headaches associated with handling cryogenic fluids. Only their 4th stage uses liquid propellant, hydrazine a monopropellant. Having a 3 stage solid propellent stack is actually quite an achievement.

Re:Title is wildly misleading

[dunkelfalke]

Only cryogenic fuel rockets. Hypergolic fuel rockets can be fuelled way earlier - the missiles can stay fuelled up to a decade or so.

Re:Title is wildly misleading

[Anonymous Coward]

It's a hell of a lot cheaper to build a solid rocket than a liquid one. No complicated plumbing, no meticulously engineered turbopumps, just burny stuff and a nozzle (mostly). India's innovative and inexpensive launch vehicle uses a combination of solid and liquid stages. The specific impulse is shit, to be sure, but then again, *any* rocket has shitty specific impulse in the atmosphere, so it isn't much of a downside when you consider the simplicity benefits.

Re:Title is wildly misleading

[Anonymous Coward]

yes

Re:Title is wildly misleading

[Enigma2175]

Usually you have to fill liquid fuelled ones up just before you launch them. This means if anyone is observing you, they know in advance that you're going to launch.

This can be a disadvantage for certain applic@.m,mk
no carrier

Yes, but I think they will know you are launching when you go stand this thing up on the launch pad and fuel the second and third stages.

Re:Title is wildly misleading

[Enigma2175]

As commented above, the article at:
http://spaceflightnow.com/2016...

notes that all 3 stages are solid propellant systems.I see no mention of liquid propellants, though there may be some for the spin-up and station keeping.

If this really is a completely solid propellant system, the cost savings would be incredible. One number I saw was 1/3 the cost of traditional systems. At least for earth orbit, that should give the Space-X crew some competition for a while - which is good for everyone.

I agree that this could be a cost-efficient way to get to orbit, but it's not competition for the Falcon 9. This launch boosted a 365 kg satellite into GTO. The Falcon 9 can boost 8,300 kilograms into GTO. The Epsilon costs $38M per launch, so for this launch the cost to orbit was about $104K per kilogram. The Falcon 9 costs $62M, so for a max payload mission it would cost about $7500 per kilogram. They're not even in the same ballpark.

Re:Title is wildly misleading

[Anonymous Coward]

Wot's space ever done for us? Ok, Ok, other than GPS navigation, weather forecasting, worldwide broadcast media, communications, and the miniaturized personal computer, wot's space ever done for us?

Re:Title is wildly misleading

[Anonymous Coward]

>This means if anyone is observing you, they know in advance that you're going to launch.

So.

Must everything... especially gigantic, loud, expensive, fully staffed, and huge land-use projects be expected to be secret?
If there is a nutter possessed to reach that launch site, you keep talented security around. :)

** reminds me of that time I was commissioned to sneak into a ... [Bzzzz Bzzzz Bong Screech (32-baud modem noises) ]
END OF LINE

Re:Title is wildly misleading

[Anonymous Coward]

This is news for nerds. Any "nerd" who doesn't think rocketry is awesome should probably turn in their badge on the way out.

I think Rockety is awesome when it's done by NASA and not con-artists that cut corners with safety to make a buck.

You mean like Challenger?

Re:Title is wildly misleading

[K. S. Kyosuke]

The sane high-thrust booster choice is RP-1/oxygen or even CH4/oxygen these days. Indeed I'm speaking about the fuel cost. Liquefying oxygen or methane per unit of mass is pretty much the lowest-cost thing one could come up with - below one dollar per kilogram for sure. Mixing a heterogeneous mixture of solids and curing it in a casing is definitely more expensive. Apparently, the cost is something like 50 Euros per kilogram for Ariane 5 boosters. Now that's of course meaningless if the liquid rocketry gadgets are as expensive as it they have been until now, and for many systems, I'd expect an SRB to be preferable for the "initial kick" , but with engines like Raptor or BE-4 on the horizon, this could change.

Re:Title is wildly misleading

[dbIII]

Your thanks is appreciated supreme arbiter of rocketry.

Re:Title is wildly misleading

[dbIII]

other people actually enjoy laughter.

Indeed, but normally it take a little more than acting like a complete idiot to make them laugh instead of just writing you off as a complete idiot.

Re:Title is wildly misleading

[TimothyHollins]

Indeed, but normally it take a little more than acting like a complete idiot to make them laugh instead of just writing you off as a complete idiot.

Bob, we've already established that you are more of a Krampus than any authority on humour, so this just comes off as sad.

Are you grumpy because people around you are happy during the holidays?

Re:Title is wildly misleading

[stoatwblr]

Solid fuel rockets are generally less dangerous than liquid-fuelled ones (until you light them).

As first stage boosters they're quite useful lifters but I wouldn't want to go to orbit on one.

Re:Title is wildly misleading

[stoatwblr]

"Hypergolic fuel rockets can be fuelled way earlier"

Those tend to be something you don't want to spend any time in close proximity with. Hypergolic fuels and biologicals tend not to make a good combination - and unlike space, metals tend to corrode when in an atmosphere so the risk of long-term leakage is substantial.

Re:Title is wildly misleading

[stoatwblr]

"Apparently, the cost is something like 50 Euros per kilogram for Ariane 5 boosters. "

The higher cost of the materials is more than offset by not needing to have pesky expensive things like turborocket engines at the blunt end.

As for the ESA published cost, having worked on the peripherals of the organisation for the last 15 years I could easily believe that figure being 20 times higher than the ACTUAL cost of the material and manufacturing, based on inflation of figures as they pass through the organisation.

Re:Title is wildly misleading

[K. S. Kyosuke]

The higher cost of the materials is more than offset by not needing to have pesky expensive things like turborocket engines at the blunt end.

The single most important reason for those "pesky expensive things" to still be peskily expensive in the 2010s is that nobody cared about making them cheaper, both in terms of manufacturing and in terms of being able to use them multiple times. Now that companies like SpaceX and BO started caring about these things, there's very likely a shitstorm coming for the legacy designs.

Re:Title is wildly misleading

[dbIII]

I clearly had no way at all to be able to tell the difference between you acting like a total idiot in a failed attempt to be funny or merely being one of the many "it's not US space so let's dump on it without having a clue" losers.
Please keep that in mind the next time you attempt to be funny but fail so dismally.

Also why are you trying so hard to convince me you were joking?

Re:Title is wildly misleading

[dbIII]

Grumpy? From the guy making an attack on JAXA or pretending to do so?
Now you are making me laugh - what a loser!

Re:Title is wildly misleading

[dunkelfalke]

When it comes to liquid fuelled ballistic missiles, they usually are factory fuelled (UDMH + RFNA) and are stored that way for "fucking years, absolutely years" and don't leak (that's why they were so expensive to build). And when the ballistic missiles approach the end of their warranty, they can be used for satellite launches.

Re:Title is wildly misleading

[TimothyHollins]

I clearly had no way at all to be able to tell the difference between you acting like a total idiot in a failed attempt to be funny or merely being one of the many "it's not US space so let's dump on it without having a clue" losers.
Please keep that in mind the next time you attempt to be funny but fail so dismally.

This is something you should take up with your grade school teacher and/or parents. I claim no responsibility for your Trump-grade intellect.

Also why are you trying so hard to convince me you were joking?

Because your saltiness amuses me.

Re:Title is wildly misleading

[TimothyHollins]

Bob, you aren't making yourself look better here. It's bad enough to be Krampus, don't be illiterate too. Nobody wants to hug a kid that special.

Also, you don't have to answer twice to my posts. I get that you need to rest between these intellectual exertions, but it's possible to just save the first response to a text file and then load it up when you have rested.

You're welcome.

Re:Title is wildly misleading

[dbIII]

You are still trying?
Where the fuck was the joke? It looks to me that you just didn't read the summary and wanted to have a go at a rocket scientist to inflate your ego?

Re:Title is wildly misleading

[dbIII]

WTF is your problem kid? What's with the hate of JAXA?

Re:Title is wildly misleading

[dbIII]

Also, you don't have to answer twice to my posts.

Why not - you replied twice to my initial post after all.
Just admit to yourself that you fucked up by not reading the summary before writing your petty attack on JAXA and then later pretended it was a joke to avoid looking like the idiot you are. No need to admit it to me since I worked that out from the start.

Re:Title is wildly misleading

[TimothyHollins]

WTF is your problem kid? What's with the hate of JAXA?

Bob, the only hate here is between you and humour.

Re:Title is wildly misleading

[TimothyHollins]

Admittedly, you are far better than any joke I could tell, so in that regard you have me beat. Well done.
I think we've already covered your personal war on literacy, no need to rehash.

Re:Title is wildly misleading

[TimothyHollins]

Or you could figure out that very few people are so insecure that they would need to lie on a pseudonymous forum. Your projections onto me serve only to embarass and, were this not a pseudonymous forum, humiliate you.

Re:Title is wildly misleading

[dbIII]

Not as such. Your bluff didn't work loser.

Re:Title is wildly misleading

[dbIII]

So slang guy is referring to literacy? It appears you only have one card to play even when it is ridiculously inappropriate.

Re:Title is wildly misleading

[dbIII]

Or you could figure out that very few people are so insecure that they would need to lie on a pseudonymous forum

It didn't look like a lie, it looked like full on jingoistic stupidity and despite your backpedalling I think that is what it was since there is not the most remote trace of humour in that first post. The lie comes later with your backtracking and your pointless attacks on me just because I politely pointed out your stupidity.
How the hell do you cope if this is all it takes to set you off with the "Bob", "Krampus" and "special kid" stuff? Shouldn't you be taking your medication if you are really that fragile?

Re:Title is wildly misleading

[TimothyHollins]

Haha, you're doing it again. When you grow up you'll understand.

Re:Title is wildly misleading

[TimothyHollins]

Slang and literacy go quite well together - in both directions one should understand one to fully appreciate the other. Only a special kind of child would fail to make that connection...

Other than that, It's not surprising that the boy who hates laughter would find stuff to be "ridiculously inappropriate".

Your are just adorable.

Re:Title is wildly misleading

[TimothyHollins]

Bob, calm your tits.

I don't want you to get a heart attack. You are my Slashdot entertainment for the time being and I want you hale and flailing.

Re:Title is wildly misleading

[stoatwblr]

You're quite right, but the engines are still expensive enough that virtually all the new designs are centred around getting them back for re-use.

If they're basic and cheap enough you can treat them as disposable, but noone is brave enough to make a Sea Dragon (which is reusable anyway).

Re: Go go Godzilla!

[Anonymous Coward]

Oh no the 'Murican has put his bleached teeth into a very very fat hamburger!! (This is how stupid your Godzilla-"joke" sounds)

Re: Go go Godzilla!

[Anonymous Coward]

Both of you seem to have missed something... that wasn't a joke, these are the lyrics to the chorus of Blue Oyster Cult's "Godzilla", released in 1977. The following lyrics go: "History shows again and again, How nature points up the folly of men". Well it has certainly shown up the two of you.

Solid fuel ?

[TheBlackMan]

When you launch it, it will shit bricks

Re:Perfect for Satellites... and Nukes

[Rakshasa Taisab]

Why are people blaming everything on Trump? He wasn't even elected or running when they started the development on this project.

Re: Go go Godzilla!

[thechemic]

How could I have missed something? I made the post as a metaphorical tribute to Japan. Perhaps you missed that?

Re:Perfect for Satellites... and Nukes

[Cytotoxic]

Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history? Because Trump has declared S. Korea and Japan to no longer be protected by the American nuclear umbrella.

Yes. So much this! Japan anticipated Trump taking office in 2017 a couple of decades ago and rushed the development of the Epsilon, which first launched in 2013. All of this so that they could have an enhanced version of the Epsilon ready for its first satellite launch in 2016, a couple of months before Trump takes office. Brilliant insight there....

Re:Perfect for Satellites... and Nukes

[Anonymous Coward]

"Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history? Because Trump has declared S. Korea and Japan to no longer be protected by the American nuclear umbrella."
Good try, I'm all for portraying Trump as a narcissistic madman, but Japan's current Solid Fuel Rocket program goes back to 1990, and from the beginning, has had a cost-cutting mission for launching satellites. (A mission not unique to Japan...)
In 1990, Trump was still working out the details his first planned major bankruptcy, with the Taj Mahal Casino.

Presidents get the blame

[sjbe]

Why are people blaming everything on Trump?

Several reasons. 1) He's an asshole and an easy target. 2) Every president gets both too much credit and too much blame. Trump will be no exception. 3) Trump has said some terrifying and ignorant and irresponsible shit in regards to nuclear weapons which is relevant to this discussion.

He wasn't even elected or running when they started the development on this project.

No but he's the guy who got elected and so his actions and opinions now matter.

Re:Perfect for Satellites... and Nukes

[wisebabo]

Did I say Japan built this thing in response to Trump? Am I claiming that Japan's nuclear reactors (including their plutonium breeder reactors) were built because they needed to make nuclear fuel for their weapons?

Of course not, however if the need arises they will surely turn towards the skills they have peaceably acquired for the production of weapons of mass destruction.

Conservatives are fond of saying that guns don't kill people, people do. Like so many many things in our technological world, (GPS, high purity aluminum alloys for centrifuges, etc.) advanced technological items can be used for many purposes (I do genetic engineering). Now we've got someone who wants to radically alter the balance of power in the world, I would say in a very short-sighted way. So people are looking anew, for their own protection, at what they have and what they can be used for.

Re: Go go Godzilla!

[fisted]

mom?
MOM?
MOOOOOOOOOOM!

Re:Perfect for Satellites... and Nukes

[Anonymous Coward]

North Korea/China may not wait for others to develop nukes. After some threats from North Korea, China could offer to step in and maintain the peace. Who better to move into our bases as the U.S. withdraws. .

Re:Perfect for Satellites... and Nukes

[Rockoon]

Did I say Japan built this thing in response to Trump?

Yes, you did.

You do understand that your post is visible to everyone, right?

Re:Perfect for Satellites... and Nukes

[serviscope_minor]

Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history?

As far as I can tell, japan has considered to not be a nuclear power almost in name only for quite a while. They have an active space programme, a strong nuclear industry with reprocessing, first world tech and science, active heavy industry, leading supercomputing capability and so on.

Yes, they are avowedly anti nuclear on paper, but when push comes to shove, it's entirely obvious they could have a nuke up in the air with pretty short notice.

Now, while they had a good space program, what they lacked was an excellent delivery vehicle. Liquid fueled rockets are superior in many regards, but as a delivery mechanism for nukes they are not. Solid fuelled rockets are stable, robust, transportable and fuelled and ready to go with no notice 24/7 for years at a time.

Now, there's not been much hurry, but North Korea has been acting more threatening recently, and China is beginning to get a bit miliraristic round that area about ownership of some islands.

I don't think there's a huge desire to become a nuclear power but this sends a message that they could and very quickly if they desired. At this point if Japan felt it had to start it's own manhattan program, well, it would probably be scant months before they reach the stage where they could drop a warhead on more or less anywhere in the world at short notice and from hard to predict locations.

Advantages:

[Anonymous Coward]

Solid fuel: Low cost, low storage requirements, quick preparation

Disadvatanges:
Low power, can't be stopped

Re:Perfect for Satellites... and Nukes

[Cytotoxic]

That's funny.

And the "this could be a missile" take isn't new, nor is it in anyway a response to today's political news.

To the wiki!

In November 2012, JAXA reported that there had been a possible leak of rocket data due to a computer virus. JAXA had previously been a victim of cyber-attacks, possibly for espionage purposes.[23] Solid-fuel rocket data potentially has military value,[23] and Epsilon is considered as potentially adaptable to an intercontinental ballistic missile.[24]

So way back in 2012 someone was trying to find out about this rocket, and probably because of its potential as an ICBM.

But yeah... because Trump.

Re:Perfect for Satellites... and Nukes

[Cytotoxic]

Oh, and whoever modded wisebabo offtopic is a little slow.

The adaptation of the solid rocket boosters from the HII-A into a stand-alone rocket has always had military implications. I don't think anyone is pretending otherwise - at least not with more than a fig leaf.

Just because his tack-on attack on Trump was silly doesn't make discussions of the possibilities as an ICBM offtopic.

Solid fuel expertise is good for ICBM's

[sasparillascott]

While solid fuel is not normally considered a good propellant for commercial launch operations, it is very good in case you ever have to field your own ICBM's. With The Donald talking about shaking things up with our allies (saying Japan and South Korea should have their own nukes), this is good expertise to have experience with.

Epsilon 2

[Tenebrousedge]

Thank you. That "article" is one of the worst things I have ever read, the only saving grace being that besides being completely contentless it was also short. And why are we driving eyeballs to this unknown newsrag anyhow?

This article, from your link describes the first Epsilon launch in 2013 and generally the development projects which led up to it. Quoting the overview:

Epsilon, which will replace the M-V rocket which was retired in 2006, is a three or four stage rocket which combines upper stages used on the M-V with a first stage derived from the H-IIAâ(TM)s strap-on boosters. It is the latest in a line of solid-fuelled orbital launch systems operated by Japan, following the Lambda and the Mu.

Historically, Japan had two space agencies, each with its own fleet of rockets. The Institute of Space and Astronautical Science, or ISAS, developed small solid-fuelled rockets, while the National Space Development Agency, or NASDA, opted for larger, liquid-fuelled vehicles.

NASDA and ISAS, along with Japanâ(TM)s National Aerospace Laboratory, merged in 2003 to form the Japan Aerospace Exploration Agency, or JAXA. ISAS operated the Lambda and Mu rockets from the Uchinoura Space Centre, while NASDA flew the N and H from Tanegashima.

I'm not particularly sure why this is news, but especially puzzled at the choice of headline. This is apparently the second Epsilon launch, but not exactly JAXA's first time on the ranch. It's their fourth launch this year, and the next one is in mid-January. It must be a slow news day. Anyhow, for anyone else's further purview, the Wikipedia article on the satellite it's launching is here, and it could perhaps be considered a replacement for this one which was deactivated in 2015.

Re:Perfect for Satellites... and Nukes

[wisebabo]

Sorry, I guess what I wrote could be interpreted in the wrong way:

"Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history? Because Trump has..."

I guess I could have been more clear: "Why would Japan want to use it in such a way after having avowed..."

As someone who been following national space programs for decades (and regularly attended JPL conferences), it was not my intent to say that Trump was responsible for Japan's solid rocket program (as if). Nitpicking aside, my apologies for the confusion, however the rest of my points (repeated I see by numerous other commentators) stand.

Throttle Control?

[MrLogic17]

From my limited KSP playing experience, the biggest drawback for solid fuel propulsion is the inability to throttle back (or shut down) the rocket.
I have seen a growing number of non-booster stages that use solid rocket fuel systems. Has this problem been solved?

Re:Throttle Control?

[CrimsonAvenger]

From my limited KSP playing experience, the biggest drawback for solid fuel propulsion is the inability to throttle back (or shut down) the rocket.
I have seen a growing number of non-booster stages that use solid rocket fuel systems. Has this problem been solved?

Well, yes and no. A solid-fuel rocket cannot be throttled. But a hybrid system (solid fuel plus liquid oxidizer) can be throttled and/or shutdown, by throttling the flow of oxidizer.

It's got some of the advantages of solid fuel, and some of the advantages of liquid fuel.

Unfortunately, it's also got some of the disadvantages of both solid and liquid fuel, which is why not much effort has really been put into it much past proof-of-concept....

Re:Throttle Control?

[Anonymous Coward]

Another thing to bear in mind is that real world SRBs generally have gimbaled nozzles, so the KSP problem of the thrust running away from you and screwing up your flight profile isn't so much of a factor because you have better directional control.

Re:Throttle Control?

[stoatwblr]

"A solid-fuel rocket cannot be throttled"

Your hybrid is one approach. The other is to use solids for the lower kick stages and throttleables for the finer work.

Pegasus being an example of a 3-stager made of solids with a throttleable 4th stage used if needed.

Re: Go go Godzilla!

[Ol Olsoc]

You just told the guy who wrote the OP what he "missed"?

BoC's Godzilla is a highlight of Rock music, amazing the original AC in this thread didn't get that.

History shows again and again

How nature points up the folly of men

Godzilla!

Re: Go go Godzilla!

[Ol Olsoc]

How could I have missed something? I made the post as a metaphorical tribute to Japan. Perhaps you missed that?

Some AC's ain't got it going on. Hard to imagine he didn't get the reference.

Re:Perfect for Satellites... and Nukes

[Ol Olsoc]

Actually it's not perfect for satellites (and much worse for manned missions, remember Challenger)

To be precise, the Challenger accident was caused by operating the SRB's out of their design range. While they were not supposed to be used at less than 50 degrees, the night before the launch, the temps dropped to 18 degrees F, and were still below too cold at launch. The joint seals did exactly what the were expected to do when launched out of design window.

It was one of those cases of humans trying to trump physics with the suit's decisions.

Re: Go go Godzilla!

[budgenator]

Blue Oyster Cult had two songs worth listening to and "Godzilla" wasn't one of them.

Re:Perfect for Satellites... and Nukes

[budgenator]

They wouldn't even need a nuke, 350Kg of scrap iron in a reentry vehicle coming down from 20,000 mile up is going to hit the ground like one. It would be more than enough to pound N Korea's nuclear program into oblivion.

Re:Perfect for Satellites... and Nukes

[Anonymous Coward]

Why would Japan want such a thing after having avowed a no nuclear policy after being subjected to the only nuclear attack in history?

As far as I can tell, japan has considered to not be a nuclear power almost in name only for quite a while. They have an active space programme, a strong nuclear industry with reprocessing, first world tech and science, active heavy industry, leading supercomputing capability and so on.

Yes, they are avowedly anti nuclear on paper, but when push comes to shove, it's entirely obvious they could have a nuke up in the air with pretty short notice.

Now, while they had a good space program, what they lacked was an excellent delivery vehicle. Liquid fueled rockets are superior in many regards, but as a delivery mechanism for nukes they are not. Solid fuelled rockets are stable, robust, transportable and fuelled and ready to go with no notice 24/7 for years at a time.

Now, there's not been much hurry, but North Korea has been acting more threatening recently, and China is beginning to get a bit miliraristic round that area about ownership of some islands.

I don't think there's a huge desire to become a nuclear power but this sends a message that they could and very quickly if they desired. At this point if Japan felt it had to start it's own manhattan program, well, it would probably be scant months before they reach the stage where they could drop a warhead on more or less anywhere in the world at short notice and from hard to predict locations.

Rumor has always been that Japan always likes to keep plutonium on hand, knowing that they could make a nuke in a month or so, if necessary. That's why alarm bells go up, whenever Japan is stocking/holding onto way too much plutonium and not e.g. shipping it off to the US.

Why it's important

[John Bayko]

There is a political aspect to it. Solid fuel rockets are ideal for ballistic missiles because they can be kept on standby with little to no maintenance. This is a dual-use technology that means Japan could produce intercontinental ballistic missiles if it wanted to. This is the exact thing North Korea was forbidden to do by the UN.

Of course more whining from North Korea is not likely to be noticed, but it won't help relations with China either.

Do you even book

[Anonymous Coward]

Tom Clancy - Debt of Honor
Drop mic..

Re:Perfect for Satellites... and Nukes

[Anonymous Coward]

> Why would Japan want such a thing after having avowed a no nuclear policy...

Why must the use be nuclear? Sure, dis the satellite use and think straight military... that's fine. But why nuclear?

Decision Time (tm)
    You are a general in the Japanese army. You have the capability to 'reach out and touch someone' accurately and with no casualties on your side. Your touch can include a WIDE VARIETY of payloads aside from nukes.

    ( Of course today is the office party, so you choose to launch confetti into the air at 10km. But next time... ! )

Re:Perfect for Satellites... and Nukes

[SuricouRaven]

It'd leave a big hole, but it's not even close to a nuke. If you can aim it well enough, it's still good for precision strikes when you just want to blow up a single facility without having to deal with air defense.

Missile vs Rocket design

[Tenebrousedge]

I have a hard time agreeing with that. I'm not a rocket scientist, but I think there are a number of things which detract from that argument. The principles of solid fuel rockets are pretty solidly nailed down, especially in terms of chemistry, and while solid fuel does have certain conveniences, ballistic missiles can run just fine on alcohol, jet fuel, kerosene, or whatever is lying around. Almost anyone could produce ballistic missiles, it's a lot easier than putting something in orbit. JAXA building one solid fuel rocket every two or three years is not actually equivalent to having the ability to manufacture ballistic missiles en masse. Turns out, you build missiles differently from rockets, which might explain why they have different names. Playing around with KSP will probably give you the most insight into the kind of structural differences you would need to adapt this technology, but rockets tend to be fairly precisely designed around mission requirements, so if you change those drastically you would still need to re-engineer your rocket significantly. Also, it's extremely unlikely that they were manufacturing this with mass production in mind (i.e. hundreds at once) so that capability would also need to be developed. Also, one of the fun features of solid fuel rockets is that shutting them off once you turn them on can be a challenge, so anything that's going to supply you with the velocity to reach orbit is going to be complete overkill if you happen to not want to do that, so you can't just slap a warhead on top of this rocket and call it a day.

This could be considered a starting point for a ballistic missile program, but so could a copy of John Clark's Ignition!. The problems of ballistic missiles and of orbiting satellites are not as similar as they might appear, and in no sense could these rockets be considered "dual use". And remember that thing where the US did the reverse, trying to turn Redstone ballistic missiles into orbit-capable launch vehicles? Here's a list of Redstone launches. Note that the word "failure" occurs 80 times in that list, and Redstone was considered a reliable rocket. So essentially rocketry is difficult, and this should not be considered a strategic move. It might be useful for some political purpose to pretend that it is a strategic move, but I tend to doubt that as well -- as you say, if it's just NK that gets upset no one will care.

Re:Missile vs Rocket design

[tibit]

A ballistic missile doesn't have a problem with excessive velocity as long as it can survive the aerodynamic pressure and heating. Trajectories can be designed to mitigate the fixed burn time of the motor. So a solid-motor ballistic missile isn't a big deal. Even if you didn't have any way to throttle it down. Alas, solid motors can certainly be throttled down by blowing some of the exhaust sideways, and even turned off by blowing out the flames - as long as you design that capability in.

Re:Missile vs Rocket design

[Tenebrousedge]

Yes, you can design solid rockets so that they can be throttled or turned off, but at that point you're lifting a lot of useless fuel, and given that this rocket was used to put something in orbit, that's going to be quite a lot of fuel. Using a non-optimal trajectory adds quite a bit of aerodynamic load and heat. With rockets you of course want to minimize the amount of non-payload mass you're moving, so if you're anticipating that you might not want to take the most efficient path through the atmosphere, you have to add mass to get the structural strength to be able to do that. I don't have any solid figures to be able to estimate exactly how big of a problem it would be, but NASA seems to shoot for a factor of safety of around 1.4 or 1.5, which means that you don't have a lot of room for error.

I don't design rockets, and I don't design ballistic missiles. I am however pretty confident that this is a rocket, not a ballistic missile, and that it could not easily be adapted to be one. Where you are taking your payload is a fundamental design concern, and again, I feel like this point is well supported by the early history of rocketry.

Re:Missile vs Rocket design

[lucien86]

Oh dear... There really is not that vast a difference between a high energy sub-orbital flight and a full orbital flight. With a little modification ballistic missiles can and have been used to launch satellites, and visa versa orbit capable rockets make very good missile platforms. In the old cold war days the biggest nuclear warheads could only be delivered by planes or large space rockets - like the Soyuz for instance.. In its early days the Space Shuttle was described as the most capable nuclear warhead delivery system ever created.

The only real difference between a rocket and a missile? is, well semantics - a ballistic missile is technically a rocket, and a rocket is technically a missile.. :)

On solid based verses liquid fuelled rockets there is a huge difference. Once assembled solid fuel rockets require very little regular maintenance and can be launched in minutes or even seconds. Liquid fuel rockets require liquid oxygen, which is dangerous, corrosive, super cold, and highly flammable - and very complex to handle. It also takes something like 6 to 12 hours or even more to fuel a liquid rocket before it can be launched. Alternatively if liquid fuelled rockets are kept fuelled it doesn't take very long before they need to be completely dismantled and overhauled, or even replaced..
In other words for the military solid fuel rockets are far cheaper (maybe 10 times cheaper), far safer, fire quickly, require smaller launch systems and less personnel, and in general make much better weapons.. You can look it all up on Wikipedia.

Re:Missile vs Rocket design

[Tenebrousedge]

There is no difference between a high-energy suborbital flight and an orbital flight except for all that horizontal momentum. If you're designing a rocket, your first consideration is what payload you want to get where. Rockets scale really, really badly, which is why we divide them up based on whether they're intended to be used short range, long range, intercontinental, or orbital. Yes, if you're not too picky, you can use an orbital rocket as a ballistic missile, but you're better off designing your rocket as an ICBM to start with, especially if you're going to end up needing to design it for mass production as well. This could conceivably be the origin of a ballistic missile program. I'm pretty sure it's not a ballistic missile. You may note that it was not in a ballistic trajectory for the majority of its flight, and that it did not cause anything to blow up. I believe this to be intentional on the part of the designers.

WHY?

[Anonymous Coward]

Why, from the main SD page if I go to the bottom and click on Wednesday (yesterday), does it got to:
https://science.slashdot.org/?...
instead of
https://slashdot.org/?issue=20...
Science today, some other random category on other days.
Is slashdot falling apart at the scripting seams?

Re:Perfect for Satellites... and Nukes

[budgenator]

your right, my back of napkin says about 5 ton of TNT. I assumed that because a 1/4 inch of rain on NYC releases a 1/4Kt that it would be higher.

Does this mean...

[stoatwblr]

... That Japan has stopped assembling checklists of things to do to build a rocket (then firing them off and finding that things seldom go to plan) and actually started testing every step of the way as well as taking input from the rank-and-file workers (This was one of the prime causes of past failures. Lowly workers would notify that XYZ was incorrect but be overruled by managers who knew better because they were highly paid managers, not lowly workers who actually put the things together(*))

(*) This culture was one of the prime contributors to Fukushima occuring. GE consultants told Tepco management NOT to put the generators down by the plants during the construction of the site because of the risk of flooding if there was a major tsunami. Tepco management smiled and nodded - and put the generators there anyway, because they knew better than the (non-management) consultants.

Re:Perfect for Satellites... and Nukes

[stoatwblr]

If SLS wasn't a rube-goldberg contraption, a leaky O-ring wouldn't have mattered other than causing a slight asymetry in the thrust.

if SLS wasn't a rube-goldberg contraption, a bit of shedding tank insulation wouldn't have gone anywhere near the flight surfaces of the actual spacecraft.

If you were to launch a solo SRB with a capsule on the end at 18F, noone would even need to worry about leaky o-rings, other than the risk you'd need more fuel burn in your final stage to achieve the desired orbit height.

Even with the originally designed liquid boosters, SLS would have been a rube-goldberg contraption.

Re:Perfect for Satellites... and Nukes

[Rockoon]

I guess I could have been more clear: "Why would Japan want to use it in such a way after having avowed..."

So you anwered a question that wasnt asked, while pretending to answer the question that was....

Got it. Dishonest fuck detected.