Venkat’s phone rang in the middle of a paragraph, as it usually did. Venkat’s time was generally divided between reading reports (or, not nearly often enough, papers exploring the theoretical possibilities of magic, if humans could ever get it to work) and writing letters thanking, pleading, or ordering somebody to do something on behalf of Project Ares. It was all important, but no matter how important it was, there were dozens of people with his office phone number who thought their issues were more important. A few of them were even correct.
He checked the caller ID. Bruce Ng. Well, Bruce never wasted Venkat’s time with trivialities. Bruce never had any time of his own to waste.
“Hello, Bruce,” he said as soon as he picked up the line. “And how are things in sunny California?”
“I know there’s a sun in theory,” Bruce said. “Not by direct observation. I’ve been working for over a month to find some way to make the MAV landing stage work as a booster. I’m calling you to tell you it can’t be done.”
Venkat leaned back in his chair. “I’m listening,” he said. “Tell me why a step that’s absolutely indispensable to Mark Watney and friends making a direct rendezvous with Hermes is impossible.”
“It comes down to weight and timing,” Bruce said. “The whole point of keeping the landing stage on and running the pony engines on it is to gain surplus delta-V to make up for the weight we can’t shave off the MAV. We’d need to reduce a craft that weighs twelve and a half tons empty by over five tons to achieve escape velocity on internal power alone. We haven’t been able to find more than two tons without taking steps that render the MAV nonviable for long-term habitation- that is, we have to put a hole in the hull to make it lighter. That would take away the Sparkle Drive option as a backup system.”
“Yes, I understand all that,” Venkat said. “But that’s what the landing stage and the engines off of Friendship were meant to overcome.”
“And we’ve tried it in every configuration possible,” Bruce said. “We’ve tried launching it fully fueled, on the assumption that the ponies can find a way to transmute or synthesize hydrazine. We’ve tried ripping out absolutely everything and just using the descent stage as a framework to hang the pony engines on. And, of course, we asked Starlight Glimmer to make larger batteries that could run the engines for a full three-minute burn instead of the one minute we originally planned.
“But it all fails in the sims, Venkat. Nothing we try gets more than a thrust-weight ratio of 1.3. A three minute burn just barely gets the ship to the height of the Schiaparelli Basin rim, when you factor in gravity and air resistance. The sims routinely show a failure rate of fifteen percent attempting to decouple the landing stage, ignite the first ascent stage, and reorient the craft. And by failure, I mean surface impact before the procedure’s complete. And even the eighty-five percent of successful flights yield only an average delta-V gain of two hundred meters per second. That’s out of over five kilometers per second we need.”
“Okay,” Venkat said. “So what happens when you move the pony engines to the first ascent stage?”
“No improvement,” Bruce said. “Without any way to decouple the engines and their batteries, they stay on as dead weight after they burn out. If we cut the pony engines to fifty percent thrust we might be able to stretch them through the whole first stage burn, but the efficiency losses mean they don’t quite get us to where we need to be. And we lose the most efficient portion of the ascent burn to that added eight tons of engine and batteries.”
“Bruce,” Venkat said, marshaling his thoughts carefully, “I don’t need to tell you how bad this news is. You know better than anyone. But I’m not hearing much in the way of potential solutions.”
“We’re… still working on it,” Bruce said. “But we’re at the point that we need some input from the ponies. Is there any way to lighten their engines, or to modify them so they produce more thrust faster? And I know we’ve turned off the email exchange, but I wanted to ask for a waiver so I could send them the work we’ve done so far through Pathfinder.”
For a second Venkat lost the power of speech. When he recovered it, it still spluttered like a car with a bad injector. “Wha-bwuh-wha… Bruce, you are two thousand miles closer to the Pathfinder relay than I am. You have a team who knows intimately the problems we’re having just getting a signal. The data stream’s been getting parity check errors on data packets for the last two days. You know why we decided to shut down everything but the bare bones. And if you thought we could still send your data, you wouldn’t ask me for confirmation. You'd just do it.”
Venkat heard Bruce’s sigh over the line. “I know,” he said. “And you’re right, we can’t load up the link with a ton of data when it’s barely good enough for emergencies. But the alternative is that we lose more than a month. A month in which we could work the problem.”
“Well, continue working it from your end,” Venkat said. “I’ll try to drop the problem into the morning check-in, but no promises.”
“Thanks,” Bruce said, and cut the connection.
"So, obviously, something else will have to be thought of..."
Solid rocket boosters.... somehow
Rainbow Crystal rockets (holy shit the Rainboom they will cause during ascent)
they could turn some hab canvas into a hot air balloon! Dragons are full of hot air! Its perfect!
9003770
Maybe by using the perchlorates that they both know how to collect and blow up?
Calling it now that they find a way to make the magical chaos crystals (oh my word I made an unintentional Sonic the Hedgehog reference didn't I) to help power the ship somehow.
Magical unicorn... weight reduction spell? If everything weighs less than I'd assume the engines will be more efficient... I dunno. I feel like we may have covered this already in a prior chapter, but it's late and I really don't have the energy to go through a few hundred sols worth of chapters, so apologies in advance if this idea was already ixnayed.
9003793
problem: no trashcans to fill with BOOM....
9003793 and containing them in jury-rigged casings made from pieces of hull from the Amicitas?
9003793
Basicly nuclear explsoion propelled rockets.... don't remember if its been done/ thought up by someone....
9003793
I was referring to containing it actually.
So here's a REALLY stupid question: what if they ran the conventional engines and the Sparkle Drive at the same time?
Each teleportation would gain them... what, about 5 feet or so? The craft would retain any velocity that had been gained prior to the beginning of each jump, and theoretically in the short time between each jump the engines would be increasing ship's velocity going into the next jump...
IDK, Kris. From where I'm sitting doing my napkin math (assuming I'm not using any flawed premises), it should work out
9003829
An Orion drive.
If the crystals have a self replicating enchantment, what's supplying the magic? And can't Starlight rip the enchantments from the crystals to power her spells? Or are the crystals pulling magic from somewhere other than the veggies to maintain their charge and can they use that to power the magic engines.
All else fails I guess they could strap an engine bell on the RTG and make a NERVA.
I wonder if they could boost the power and magic battery drain rate by having Starlight TK the ship up on liftoff, since the incident with removing the battery showed she can TK something up while standing in it (as does her levitation spell, come to think of it).
9003811
Twilight demonstrated a gravity modification spell in season 3. She could probably water-Morse the spell formula to Starlight. The question is if they can make, charge and carry enough magic batteries to both empower Starlight and the Sparkle Drive in the amount of time they have left.
So, if the rainbow crystal is self regenerating, how far does this ability go? I feel like that could near infinitely power the engines, if the regeneration could weave itself into engine juice.
They could always use magic to bend the space around the ship, so the gravity wouldn't pull the ship down, but up. I am pretty sure that the spell that changed the bird into an orange, realy didn't change the bird. It bent the space so it would be percieved as orange, otherwise it would drop dead. Similar spell could be used to bend the space so the gravity would aim in oposite direction. I persume that's what Twilight did in Crystal Empire. Also theoreticaly gravity consists of gravitons. Magic could change the direction those gravitons fly and create antigravity or change the property of the ship so instead of pulled down it will be pushed up.
9003876
Or if there's not enough magic, mana, life force, whathaveyou, they could just make it so Starlight lifts the entire thing while they're rocketing up. It would only need a little bit of energy too, since the acceleration would mean any force you added, would greatly increase it.
9003833
Might work—but it makes the Hermes intercept all-or-nothing since there will be nothing left in the mana batteries to get them to Earth. Of course, that's how it went in the original story, so that increases its likelihood!
9003848
The RTG doesn't generate nearly enough power for a NERVA. The amount of heat it puts out is equivalent to a powerful hair dryer, 1400 W. For NERVA you need megawatts, not a measly kilowatt or so.
DF: Hey, Starlight, can you use that perchlorate spell again? I want to make some solid boosters...
SG: *holds up plant mister*
9003928
I know that. It was more of a KSP joke than a serious suggestion.
9003860
I don't think the spell that convinces your local mass that it changes state in a fundamental force system that doesn't have states can be described or taught via alphanumerics.
All mass exerts the same pull equally. You pull on the Earth exactly as much as Earth pulls on you; Earth simply has more inertia than you, so you move untold x-illions of times more than Earth. That spell tells your atoms that they actually push other atoms now, thank you very much. Think of gravity as a number that has only absolute value, distance from zero. That spell introduces negative integers to a system with no concept of such.
Put another way, you are changing the polarity of something that doesn't have poles.
You should get Grammarly. It found a whole bunch of spots in this chapter where you accidentally added an extra space.
i.imgur.com/pN7fqAZ.png How long has that been happening and no one noticed?
That does not bode well... Hopefully they'll figure something out. Other than getting out and pushing. :B
9004003
You do know that gravity is more complex than that, right? Gravity is different everywhere and is affected by the distance between bodies.
where
m_{1}
andm_{2}
are the masses of the bodies,r
is the distance between the two centers of masses.G
is a constant. Found here.At the surface of the earth, this equation comes to
9.81 \frac{m}{s^2}
as the acceleration due to gravity. As you get further from the planet, the affect of gravity on you weakens, so you accelerate slower.Declaring that the spell's effect has to be due to negative mass is a rather narrow viewpoint. After all, humans defy gravity all the time with rockets, airplanes, and even simply holding something in a hand. If you were able to accelerate something 9.81 meters per second square in the direction straight up, congratulations: you have successfully reversed gravity.
Don't be ridiculous. Physics is a well-known discipline and instantaneous changes to the environment in physics problems are common. A charged particle moving between different magnetic fields is an easy example.
How close do the mana batteries need to be to the craft to power it?
We know life support system was supposed to power its far end (suits and the ship) over interplanetary distances. Would it be possible to replicate that on a smaller scale?
Perhaps they could leave the batteries for the thrusters on the ground? They'd only work during first stage of ascent anyway, but then they wouldn't be a dead weight anymore.
9004062
That's an HTML standard, actually. Any standards-compliant web browser should treat any amount of white space as a single space.
There's specific codings for things like paragraphs.
9003848
The plants in the cave farm supply a continual, low-level magic field (which they've been using to keep their batteries charged). Better yet, they've been setting up a daily magic field to keep Dragonfly healthy. So there's more than enough magic to manage a minor enchantment...
Theres another design that gets them delta V, but it involves a rediculous amount of construction using material thats very difficult to stabilise.
The Icarus Ice launch ramp from When Worlds Collide? Using a Rocket Sled.
Oh well, scrub Project Rubber Duck.
And there aint no eroded but still open volcanic throats they can try using as a Verne Cannon.
forget chances of million to one, you wouldnt be anywhere that lucky.
So, looks like theyll be trying to get into space on the Changeling Space Program Mark 1? A cardboard box on top of a solid fuel explosive?
9004123
Getting in to space is easy. The current design gets into space. Sparkle drive included.
It is a choice:
Rendezvous with hermes OR use the sparkle drive.
A 15% failure rate on the first stage might be acceptable, if they need that Dv AND have an abort plan.
Think bringing extra food, leaving it as breadcrumbs for the trip home.
9003891
A lot of people might think this idea is bullshit, that you can't lift something you're standing on, but Starlight herself cannonized lifting yourself with magic so it is possible. The only question is if they'd have enough magic to spare and if Starlight could lift enough weight to cancel out the 5-6 tons they're having a problem with.
9003848
Imagine the Crystal growing and eventually filling Mars' surface with rainbows. If the Planet didn't hate the Equestrians to death before this point, It surely will do soon.
9004201
Hmm… 3.711 m/s² (mumble…) 241.17 m/s… (mumble…) 49.76° N, 339.26° E… (mumble…) 155.79 m/s.
Well, if Starlight were able to cancel the weight of the MAV with respect to Mars, i.e., just the gravitational force pulling the MAV and Mars together, the MAV would immediately start moving away from Acidalia Planitia on a tangent at roughly 155 m/s (560.736 kph), the rotational velocity of Mars at 49.76° N latitude. Naturally, the velocity will immediately begin to drop due to air resistance, so the MAV still needs to fire its engines. If the gravity cancellation were timed precisely for local midnight, the velocity vector would point forward and parallel to Mars’ orbit. Accelerating on this course would put the MAV in a higher and faster solar orbit than Mars, so the MAV actually would (slowly) back away from Mars while climbing higher under the laws of orbital mechanics. At some point Starlight would be forced to drop the spell, Mars would reassert its influence upon the MAV, and my reasoning goes out the porthole. But if the MAV exited the atmosphere and reached escape velocity relative to Mars before that point, it wouldn’t matter; it would be in a solar orbit! Refine the time at which the spell is cast and the engine thrust vector, and it ought to be possible to match course with Hermes. But it’s a big “if” predicated upon (a) Starlight being able to cast such a spell, (b) how long she can maintain the spell, and (c) the mana batteries storing enough power to make it work.
About this not working: To me it's all about the descent stage. Its T/W ratio just don't add up for it to slow down the craft in a reasonable amount of time, so fix that and it might get somewhere.
A comment i left a long time ago that goes in to details, Excuse the horrible attempt at humor:
8937054
Ponies should measure the magical properties of rainbow quartz crystals.
For example by "infecting" the first (partially charmed) test battery with this rainbow effect, and then "formatting" it again.
There is a chance that "rainbow" quartz batteries are much better than plain quartz ones.
Then Maretians would strip the descent stage to the bare frame that holds only the rainbow magical batteries and (somehow boosted) magical engines, removing weak chemical engines and fuel tanks. If the descent stage could reach a stable orbit, the danger of separation would be reduced to null, and the priceless magical engines and mana batteries could be recovered by the next Martian expedition.
P.S.
I don't like the idea of Starlight lifting the ascent stage to orbit, she may tire and faint in the middle of the flight, even while having enough mana.
Besides, it is too much "deus ex machina" and not in the spirit of Changeling (or Kerbal) Space Program.
9004210
Yes, because “raInbows” and “Mars, God of War” go together so well—like fire and gunpowder!
9004011 I'm not adding them. There's something about FimFiction and C&Ping from a Word document into it that adds spaces in some place and steals them from others (especially a string of capitalized words).
"So, obviously, something else will have to be thought of..."
Turn Mars into a giant spaceship. Because it's cool.
9004312 "Die. Die. Die. Die. Die. Di - WHAT ARE YOU DOING?!"
9004242 You might have something there. Do flying chariots have some sort of runic system inscribed into them to allow them to link to pegasus magic? It would explain why they stay horizontal, rather than hanging vertically off the pegasi towing them. This is my head canon, and translates to a repulsolift system.
Apply the tech to the MAV, and you get an extra 3 m/s or so, as you no longer have gravity losses.
9004335
"Choo choo motherplucker."
9004312
Feh, wake me up when somebody steals Jupiter to use as a fuel tank…
9003787
Heh, crystals don't exactly burn up like solid rocket fuel but I was curious how much of a Chekhov's Gun these rainbow crystals were going to be. I bet they'd make awesome batteries, assuming Fireball even lets Starlight near one with her cutting horn laser. Hell, considering they're absorbing the cave farm's magic and storing it as an unformed "enchantmess", they're turning into literal batteries anyway.
Starlight better start crunching numbers, they may have more battery juice than they know what to do with in a month or two. Need to levitate the Whinnybago there? No problem! How about a thrust-multiplier spell for the MAV? Here you go, you want fries with that?
On a side note, assuming the cave farm is suddenly bursting (but not exploding!) with rainbow mana batteries, could Starlight take Twilight's teleporter drive and use the same theory to create a levitation drive? That is, levitate the object many times a second to provide actual vectorized thrust rather than moving the entire object from one point in space to another and hope you don't phase into matter while doing it... which caused the whole mess in the first place.
Oh crap, I didn't just spoil the liftoff, did I?
Has this been asked before? Why can't the Sparkle drive be used from cold takeoff?
9004411
Well, other than the facts that:
The rest is left as an exercise for the reader. Frankly, unless its spell matrix is corrected I wouldn’t trust the Amicitas’ Sparkle Drive to get them to Earth without taking another detour through the fifth dimension. The space within geosynchronous graveyard orbit is littered with space junk ranging in size from spent rocket stages and bus-sized communication satellites to flecks of paint smaller than a grain of sand. And a spatula (for a few months, at least).
9004385
They will be the equivalent of ion engines Hermes uses
Time to slap physics silly with some more magic!
9004411 Because enchanted objects, without a living will controlling them, aren't always reliable about spotting the point where the target leaves off and the ground the target is standing on begins.
9004424 They've found and fixed that last point, in theory- the Sparkle Drive won't be ducking out to Narnia or the Terran Empire or anything like that. But you easily understand how NASA would be uncertain about how reliable that option is in practice.