back to article Orion 'Mars' ship: Cosmic ray guard? Go. Parachutes? Go. Spacerock shield? Go!

NASA’s potentially Mars-bound spaceship is set for its first test flight today, with a 70 per cent chance of good weather for the blast-off. Orion on the launch pad fuelling up The space agency has just finished fuelling up Orion, which it hopes will be the successor craft to Apollo and will carry astronauts to the Moon, …

TRT
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That paint job...

reminds me of this.

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Disappointed!

This isn't the Orion spacecraft I was hoping for...

This is: http://www.scifiairshow.com/ships-orion.html

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Re: Disappointed!

Nothing like my disappointment!

This isn't the Orion spacecraft I was hoping for...

This is: http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

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Re: Disappointed!

If that existed in 1967, how come the Virgin 'spaceship' is taking so long?

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Re: Disappointed! (@Paul Crawford)

Yup. When I saw "Orion Spacecraft" I too thought of Project Orion

I confess I originally learned of it from reading Footfall by Larry Niven and Jerry Pournelle, and then being amazed to find it was actually real (as you point out).

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Re: Disappointed!

I also thought about mentioning this one, but decided that it was not something I'd be hoping for (especially if I lived near the launch site!). I too first encountered this in Footfall and then discovered it was real.

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Unhappy

Re: Disappointed!

I bought the plastic glue-together model way back when, Revell I think, it couldn't make orbit and shattered on the concrete path out front -

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Coat

Re: Disappointed!

Well as it's supposed to be a Virgin spaceship then presumably every time it gets fucked they have to start again with a new one.....

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Re: Disappointed!

With an appropriate ground plate you could live fairly near one and not be too badly off.

The one in Footfall however, would not be pleasant to be near.

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Re: Disappointed! (@Paul Crawford)

God was knocking, and he wanted in bad

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FAIL

WTF??

"4,000 degrees Fahrenheit"

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Re: WTF??

"4,000 degrees Fahrenheit"

Unit of choice for an imperial power?

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Facepalm

Re: WTF??

but... but... I thought the NASA were proper boffins. Don't they use El Reg's Unit System or, at the very least, Metric?

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Re: WTF??

No, they don't. They don't even use Imperial measurements, but some random system that uses the same unit names as Imperial but has different measurements(!) in random places where you least expect them.

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Anonymous Coward

Hope they've put extra strings on the parachute!

That six foot thick lead shield is going to be a bit weighty.

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Re: Hope they've put extra strings on the parachute!

Fortunately high density plastics do the job just as well and weigh a lot less.

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Paris Hilton

Off to the Smithsonian with ot!

the reusable craft

About as reusable as an Apollo capsule, I reckon.

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Re: Off to the Smithsonian with ot!

I think all the new capsule designs (Orion, Dragon) are designed to be reusable. They just haven't reused them yet.

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Re: Off to the Smithsonian with ot!

Dragon2 is designed to land on land. So re-using that ought to be a lot easier than something that splashes down in nasty, salty seawater. Especially if the astronauts have to blow a hatch, and the thing gets water inside it.

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Temperature

I am guessing the temperature you reach when coming back from the moon is hotter due to your hurtling back through the atmosphere faster after the return trip???

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Re: Temperature

Yes. Mars return is even faster. SpaceX's Pica-X heat shield was designed for Mars return.

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Re: Temperature

Good lord - a space fact I never knew (or considered) was that the speed you hit the Earth depends on how far out your have been. Makes sense if you are not taking engines which retard your speed back with you.

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Re: Temperature

If you're coming down from orbit, then you'll be going just a bit less than orbital velocity of 17,500 mph.

Earth escape velocity is about 25,000 mph. That's what you need in order to get to the Moon or Mars. As it takes lots of fuel to get that, it's too difficult to carry enough to slow down much on the way back. Hence you brake using the atmosphere.

From memory you only pull about 3G on normal re-entry, whereas the astronauts returning from the Moon had to put up with something like 6. And Apollo 13 was more, because they got the entry angle slightly wrong.

Obviously you want to go to Mars as quickly as possible, so there's a balance between how much you accelerate to speed up the trip, how much fuel you can take to slow down - and how much pain you're willing to put up with on aerobraking. I guess this is another reason that they want to take their Earth re-entry craft with them all the way to Mars, as it woulld take too much fuel to be able to slow back down to orbital velocity and rendevous with one (the craft may be lighter than the fuel otherwise needed). Also the Orion is a lifeboat, as you can abort directly to Earth if the rest of the Mars ship breaks down. NASA presumably decided the AA were too expensive...

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jai

Re: Temperature

but they do all this amazing slingshot actions with satellites to speed them up on their way off to the far reaches on the solar system...

can't they also factor in a similar way of slingshotting in a way that bleeds off speed so that eventually they end up just orbiting the earth. and can then drop in as a normal re-entry, or dock with the ISS and go home in the next supply shuttle or something.

it's going to add a lot of time to the mission i guess....

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Re: all this amazing slingshot actions with satellites

The tradeoff there is time spent exposed to higher radiation levels. The sorts of things we do with satellites aren't as sensitive to that as humans are.

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Re: all this amazing slingshot actions with satellites

but they do all this amazing slingshot actions with satellites to speed them up on their way off to the far reaches on the solar system...

Unfortunately, the Big Jupiter is on the OTHER side of Mars...

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Coat

Model

Ah! So it's a model of the Orion in it's launch configuration that Howard (Big Bang Theory) has recently acquired.

He also has a Space 1999 Eagle model.

It's a quiet day!

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Hold!

Some twat has sailed a boat into restricted waters.

Revised launch time now 7:17am EST (1217 GMT).

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Re: Hold!

Sink 'em!

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Mushroom

Re: Hold!

Given what happened last time, I hope not!

Icon closest thing to rocket exploding just above the pad I could find...

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Re: Hold!

WAFI's have always been a problem...

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Re: Hold!

Another hold. Ground wind violation this time.

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Re: Hold!

Ground wind violation this time.

Some of mine have been pretty loud, say the morning after curry with real ale. But no-ones ever cancelled a rocket launch on my account...

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Anonymous Coward

Its Amazing Really...

All the technical people they need to lanuch a rocket to the stars, in this case the Moon, and yet all it takes, once they're on the Moon is someone in the capsule to press a button and weeeeeeee they blast off for home.....unbelievable some might say.

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Re: Its Amazing Really...

The joys of having no atmosphere and little gravity.

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Anonymous Coward

Re: Its Amazing Really...

Funny you should say that PaulyV, when i was a nipper, we were told that the Moon had a gravity that was 'one third' that of the Earth. About 12 months ago i heard one of the BBC space correspondents say that the Moon has a gravity that is 'one sixth' that of Earth. Maybe the Moon has been on the Atkins?

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Re: Its Amazing Really...

> Maybe the Moon has been on the Atkins?

Or the Earth's gravity has increased; that is surely the only explanation for all the bathroom scales...

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Re: Its Amazing Really...

"Or the Earth's gravity has increased; that is surely the only explanation for all the bathroom scales..."

That would certainly explain mine. I presume the atmosphere has thinned out a bit now, as well, so there is reduced air pressure - which might explain my slightly expanding stomach.

But for the AC - the Moon's gravity was 1/6 of Earths when I was a nipper. (I left school in the mid 1980s.)

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Re: Its Amazing Really...

"All the technical people they need to lanuch a rocket to the stars, in this case the Moon, and yet all it takes, once they're on the Moon is someone in the capsule to press a button and weeeeeeee they blast off for home.....unbelievable some might say."

Cherrypick some data, dismiss hundreds of support staff for the Apollo LEM flight in Houston, and then, yes, you can look it unbelievable.

The Apollo LEM went through most of the same preparations that any rocket goes through: years of planning, months of readying on Earth (fueling, charging, safing), huge numbers of personnel providing navigational support, and everything else. The difference is that a few days before the LEM's launch it was put on "hold" and stored pending astronauts pressing "a button." (Where "a button" means "going through long flight check lists of preparations to launch the ascent stage, including programming the LEM's computer based on the input of navigational teams on Earth to intercept the actual orbit of the Apollo CSM, which was not exactly the planned orbit.")

Or, if you like, you could compare the Apollo LEM to the liquid-fueled ICBMs of the era. Those also required relatively minimal preparation compared to a conventional launcher.

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Anonymous Coward

2 stroke, 4 star, Diesel?

I wonder what type of fuel they used to blast off from the Moon for Earth back in the Sixties?

On earth they use Liquid Hydrogen, a volatile substance that has to be watched over by hundreds of technicians and ground staff and yet on the moon they need nobody....funny that.

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Well, being no rocket scientist I don't know for sure, but it may have something to do with the fact that Earth's average atmospheric temperature is at least 288 kelvin, whereas in space it's only 3 (in the shade).

Given that liquid hydrogen is solid below 20 kelvin and gaseous otherwise, that might explain things.

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mtp

Re: 2 stroke, 4 star, Diesel?

Launching from the Earth is much harder work than from the Moon so on the return trip huge and delicate cryogenic engines were not required.

https://xkcd.com/681/

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Re: 2 stroke, 4 star, Diesel?

"I wonder what type of fuel they used to blast off from the Moon for Earth back in the Sixties?"

The Apollo Service Module and both ascent and descent stages of the Apollo Lunar Excursion module used Aerozine 50 (a 50/50 mix of hydrazine and UDMH) and nitrogen tetroxide.

"On earth they use Liquid Hydrogen, a volatile substance that has to be watched over by hundreds of technicians and ground staff and yet on the moon they need nobody"

The Saturn V used kerosene and liquid oxygen in its Saturn IC first stage, then hydrogen and oxygen in its second (Saturn II) and third (Saturn IVB) upper stages.

The Delta IV used by Orion is unusual in that it uses hydrogen/oxygen for all of its ground (booster, core) stages. You typically want lower impulse engines like solids or kerosene/oxygen on the first stage for a couple of reasons. One, you shed weight quickly and thus reduce gravity losses during ascent. Two, you get more thrust from dense fuel motors than low density motors for a given engine weight. (The best hydrogen/oxygen engines manage a ~75:1 thrust-to-weight ratio, while SpaceX is flying kerosene/oxygen engines with ~150:1 thrust-to-weight ratios, and even the overbuilt F-1 engine of Apollo managed ~100:1.) Delta IV's engine selection was a compromise based on costs, engine availability, and engine simplicity.

"....funny that."

Not really when you look at the different situations and engineering requirements.

Regarding Earth launch vs Moon launch engines, the situations are radically different on several counts. The overriding issue for Earth launches is the huge amount of delta-V (and thus fuel) you need to get into Earth orbit. That calls for high-efficiency fuels like hydrogen/oxygen, at least in weight-sensitive upper stages. The moon's delta-V launch requirements are radically lower, and the engineering impact of being so much further down the exponential Rocket Equation curve is fascinating: you don't need multiple stages to reach orbit; you don't need high thrust-to-weight ratios (so you can over-build and simplify your engines for reliability); and you don't need high-efficiency fuels.

On the other hand, NOT having hundreds of techs and engineers and a vast support infrastructure on hand for a launch from the lunar surface means you need to make compromises in the name of reliability. The Apollo LEM used toxic propellants that can be stored without heavy insulation and boil off that hydrogen and, to a lesser extent, liquid oxygen suffered. While the LEM could've used kerosene (or ethanol) and liquid oxygen (or hydrogen peroxide) with only modest storage problems, Aerozine 50 and nitrogen tetroxide had the advantage of easy ignition: they ignited when they touched each other. Weight limits meant the LEM could only have 1 engine, so it HAD to work without adding complicated ignition systems. Hence, toxic, hypergolic propellants were used. NASA has been trying to eliminate those propellants for decades, even suggesting overhauling the shuttles to use ethanol / oxygen. They're nasty enough that even Russia has taken steps to reduce the amount of hydrazine, UDMH, and nitrogen tetroxide it splashes across Siberia from spent stages.

In the past...heck, even now, in Russia...some rockets do use the Apollo LEM's propellants because of their simplicity and storability. They were the liquid propellants of choice for early ICBMs, but much-safer solid rockets replaced them. (They're storable without refrigeration, but a small corrosion leak between hypergolic, toxic propellants can turn a missile silo into a roman candle, or at least kill the technicians with their fumes. Hence: solids.) For civilian rockets that don't need to be stored in silos for years, you have additional options like kerosene/oxygen and hydrogen/oxygen, which give better performance without as much instant lung-burning death as the LEM's propellants.

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Anonymous Coward

<Orion 'Mars' ship: Spacerock shield? GO. Parachutes? GO. Cosmic ray guard? GO!

Pensions secure for a MINIMUM of 20 Years? GO!

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Flame

Anyone produced it in Kerbal yet?

Might have to play tonight.

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Re: Anyone produced it in Kerbal yet?

I was just thinking the exact same thing.

We're all going to be screwed when the KSP team implement re-entry properly. At the moment, you can return from the Mün and slam into Kerbal at 3 Kps with a 90 degree angle and still survive.

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Re: Anyone produced it in Kerbal yet?

"We're all going to be screwed when the KSP team implement re-entry properly."

Like an escort at a power tool convention. None of the behemoth interplanetary stacks I just aerobraked into Duna orbit had a decent reentry shield.

"At the moment, you can return from the Mün and slam into Kerbal at 3 Kps with a 90 degree angle and still survive."

At least the speeds are much lower than in reality. A few minutes of heating from 3kps to 100m/s wouldn't raise skin temperatures to the extremes that a normal Earth orbit reentry faces.

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Re: Anyone produced it in Kerbal yet?

Saw a Scott Manley vid a couple of days ago where he launched using a bajillion (technical term) physics-less components. After constant acceleration towards mun it hit and bounced back along its arrival path.

The craft exceeded the speed of light.

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Linux

Ustream doesn't like me.

Having to watch this on FF on Win7 in KVM.

/fail nasa, assault your distribution platform with a common sense club

Waiting for winds to die off.

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Anonymous Coward

Take Offs from Earth are very violent affairs.

And yet on the Moon they're very 'genteel', No violence of the rocket motor, no 'heat bloom' as the capsule takes off for home and no' 'glow' of the rocket engine......maybe Nvidia or ILM can sort those things out for next time?

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