Why cant the Falcon Heavy fly in a straight line to orbit?

[K-P]

you will find that most of them think that space exploration is about altitude

It's about attitude. (like Elon Musk & co.)

[QuantumG]

Rockets are like women Billy...

[Jet Black]

So someone please explain to me why the Falcon Heavy cant just fly straight up, directly up, in a straight line to orbit? Seems this would solve their boost back problem?

So the rocket flys diagonally across the sky, it doesn't fly straight up? There must be a good reason for this, please explain?

Oh dear...

This must be trolling.

Please let it be just that.

Personally I'd place my bet on "general level of education in [insert country of the original poster here]".

Not a big deal, plenty of people ready to educate a new guy in these forums

I doubt most high schools all around the world teach even basic orbital mechanics to be honest.

[K-P]

I doubt most high schools all around the world teach even basic orbital mechanics to be honest.

Yes...

And I think they definitely should.

Considering how much e.g. the Sun is affecting our daily lives, it is truly devastating to see how little comprehension people do have about its structure, mechanisms or even size and distance from us.

Or space in general. We are constantly "in space". Space is around us. Still, lot of people see space as a separate thing from our existence and life on planet Earth. Just like the legendary gravity. That somehow "in space" the gravity works in different ways or does not exist...

Even I had only 1 astronomy-class in high school, and I went to a "mathematical/scientific" high school...!
And in elementary school we had maybe a 15 minute session about astronomy and planets at the beginning of geography book. And teacher very professionaly backed this up by saying "ok now, everybody interested in this stuff can read it at home, now then, let's start with geography of the Benelux-countries...".

OK, this is clearly a topic of its own already, but still... I can't imagine how people deciding about the guidelines of education in our country (and countries worldwide) do not recognize the importance of space sciences / astronomy even today and it's wider meaning to young people in understanding the scales of universe and opening up fresh perspectives. It is sad.

Those who have natural interest in these things will find the information and learn. But those who never get the initial spark by themselves propably will never find it in the school either. After all, it is far more important to know the geography of the Benelux-countries at that moment when solar storm is wiping out half the civilization...

[R7]

Rockets are like women Billy...

So true.

Gorgeous outside, ice-cold inside.
Awful lot of planning ahead and everything including the positions of celestial bodies must be in order to get them excited.
Then will liquids flow down-there, sparks fly and they are on fire.
Their bodies tremble and a few minutes of fierce thrusting ensues, ending abruptly with a vision of bright stars.
After excitement calms down you notice she's left you for good.


("but ... but F9R returns!?" you say? Yes, there's hope in the rocketry...)

[ncb1397]

People on this forum should remember that all the most brilliant minds in human history didn't understand orbital mechanics and gravity until a few hundred years ago - a small slice of time on the scale of human civilization. It is certainly not obvious and all the people here still wouldn't understand it without someone explaining it to them.

[Jet Black]

I think people sometimes get caught up in the idea of zero-g meaning weightless, and thinking that things just float there, when in reality things in orbit are actually falling towards the earth. The thing is they are also moving sideways so fast that by time they have fallen 10m, the surface of the earth has also fallen 10m, and because the earth is a sphere, down is now in a slightly different direction.

[Ben the Space Brit]

Um... All rockets, even over-powered giants like Saturn-V, N-1 and Energia fly pitch-over trajectories into orbit. It massively reduces the amount of fuel they use. By  slowly pitching over to horizontal flight, they get a free boost from Earth's rotation. If they tried to fly the core straight up and then used the upper stage for the transition to horizontal flight, they'd need much more fuel in the upper stage and would be able to carry less payload.

[R7]

I think people sometimes get caught up in the idea of zero-g meaning weightless, and thinking that things just float there, when in reality things in orbit are actually falling towards the earth. The thing is they are also moving sideways so fast that by time they have fallen 10m, the surface of the earth has also fallen 10m, and because the earth is a sphere, down is now in a slightly different direction.

Personally I found this introductory explanation of orbits always confusing (and wrong for circular orbits). In my mind "falling towards earth" denotes acceleration of velocity. Circular orbits have constant velocity speed. Only non-circular orbits feature velocity increase while approaching perigee.

A person who is taught centrifugal force will probably understand that in circular orbits it's magnitude equals the force of gravity.

The revelation comes when you explain the person that force perpendicular to velocity does not accelerate nor decelerate, just turn direction. Then the person realizes that in circular orbits velocity is matched to gravity so that latter just keeps bending the trajectory turning it into a circle.

edit: cheers, AnalogMan 

[Nomadd]

 If Elon's vacuum train was fast enough, you could be in orbit 10 feet off the ground. In fact, if it could go about 27,000 mph, you'd have normal gravity in the wrong direction.

[AnalogMan]

... Circular orbits have constant velocity.

I'm sure you meant to say "Circular orbits have constant speed"   

[K-P]

If Elon's vacuum train was fast enough, you could be in orbit 10 feet off the ground.

Wouldn't it be great to have a probe (or manned spaceship) on orbit of a really regular body, like Europa (and no gravity mascons like Moon has) and with no atmosphere (and drag) so you could have a stable orbit few meters above the ground and still in a freefall-state (xxxxx km/s). Maybe that would clarify things to some...?

But hey, why we just don't build ladders tall enough to get to orbit?
Much cheaper than burn fuel.

[JasonAW3]

If Elon's vacuum train was fast enough, you could be in orbit 10 feet off the ground.

Wouldn't it be great to have a probe (or manned spaceship) on orbit of a really regular body, like Europa (and no gravity mascons like Moon has) and with no atmosphere (and drag) so you could have a stable orbit few meters above the ground and still in a freefall-state (xxxxx km/s). Maybe that would clarify things to some...?

But hey, why we just don't build ladders tall enough to get to orbit?
Much cheaper than burn fuel.

Um, not too sure how that would work, as between surface features that range from a few centimeters to several kilometers in height, as well as random Water Geysers that can extend between a dozen and a hundred kilometers high by hundreds of kilometers long.

It might work at a few kilometers up, but you might still have to adjust your altitude from time to time because of geysers. (Ice build up changing the mass of teh probe, plus smacking into the ice blown out of a geyser is bound to eat away at the kenetic energy needed to maintain orbit.  Assuming a nuclear thermoelectric generator for power, melting the ice away should't be a problem).

HOWEVER; This does present an interesting possibility that I doubt has occured to anyone.

     With Europa venting water ice out into space, would the density of the ice cloud be sufficent to warrent scooping the upper plume of one of these geysers for ice that can be converted to fuel?  Assuming a scoop tanker that gathers up water ice from the geyser plumes over Europa, or one of teh other icey moons that vent geysers of water ice, orbits for several months, maybe up to 6 months, could a sufficently large quantity of water be gathered to justify the operation?  It also occures to me that this might also work with comets, should one be passing close enough by a scoop equiped probe, that a fuel gathering might be worth it, so long as good science and a sufficent amount of fuel (or in this case, simple reaction mass) could be gathered to extend a particular probe's range and duration, sufficently to warrent the risk of gathering reaction mass in the Comet's coma.

   I Know that this is a bit off topic, but the quoted comment got me thinking of ways of lowering costs for extending missions in deep space.

     By the way, Has anyone ever thought of using a Nuclear Theromoelectric generator's excess heat as a means of heating up a reaction mass, (water or some otehr gases) sufficently to act as a reaction mass?  I know we have Ion Drives now, but why not try to use as much energy produced by Nuclear Isotopic Theromoelectric Generators as possible?  the excess heat generated over and above what is needed to power a probe's electronic systems is generally dumped as waste heat, so, can it be used for something else?

[JasonAW3]

[I doubt most high schools all around the world teach even basic orbital mechanics to be honest.

MAYBE Japan, but that's more likely an elective.  Most kids have to pick it up on the streets.

     You know the type; Punk haircuts, wire rimmed glasses, wearing white leather labcoats and sneaker soled boots.  Walking around with kluged together calculators or tricked out laptops, running pirate copis of spreadsheets and databases, while drinking stove top brewed versions of Jolt Cola and overcaffinated Mountian Dew. Using abandoned warehouses and old barges to build and launch rockets that they put together with salavged sheet metal and hand built rocket engines using windshield wiper motors as fuel pumps.

You know... The Rocket Punks...

[llanitedave]

People on this forum should remember that all the most brilliant minds in human history didn't understand orbital mechanics and gravity until a few hundred years ago - a small slice of time on the scale of human civilization. It is certainly not obvious and all the people here still wouldn't understand it without someone explaining it to them.

And most of the most brilliant (male) minds in human history didn't and still don't understand women.  Which does make them a bit like rockets.

[Rocket Science]

[I doubt most high schools all around the world teach even basic orbital mechanics to be honest.

MAYBE Japan, but that's more likely an elective.  Most kids have to pick it up on the streets.

     You know the type; Punk haircuts, wire rimmed glasses, wearing white leather labcoats and sneaker soled boots.  Walking around with kluged together calculators or tricked out laptops, running pirate copis of spreadsheets and databases, while drinking stove top brewed versions of Jolt Cola and overcaffinated Mountian Dew. Using abandoned warehouses and old barges to build and launch rockets that they put together with salavged sheet metal and hand built rocket engines using windshield wiper motors as fuel pumps.

You know... The Rocket Punks...

Oh you mean like this guy?

[Nine_thermidor]

This thread is fascinating. I'm pretty much a noob/long time lurker here, and despite being really interested in planetary science and exploration, and in Spacex's exciting plans, I've never really understood this stuff. I'm reasonably well educated in science (a masters and doctorate in geology) but I was never much of a fellow for physics and maths and such. Anyway, thanks to those who have taken the time to do simple explanations here, and any other suggestions for simple introductions to orbital dynamics/rocket science much appreciated. Love reading NSF, but the jargon can be a bit overwhelming at times. I'll have to get involved with Kerbal Space Program.

[Tuts36]

With Europa venting water ice out into space, would the density of the ice cloud be sufficent to warrent scooping the upper plume of one of these geysers for ice that can be converted to fuel?

You would promptly be murdered by a screaming mob of would-be exobiologists.

[thebluemarble]

I doubt most high schools all around the world teach even basic orbital mechanics to be honest.

Even if they did, most people simply don't care about things like that when they are in high school, if they don't want to study physics or something.
They might become interested in spaceflight later on and discover how fascinating it is etc., but they don't remember a single thing from their physics classes, usually because it was presented to them in a very boring way. And people who don't consider certain subjects to be their lifelong passion need a slightly different approach.
High schools in my country actually teach some very basic orbital mechanics, even to those who choose to focus on human arts, just like I did. I remember explaining spaceflight to my classmates. I don't consider myself a good teacher, but I don't think many of them would be able to understand anything of it without help from someone who is actually interested in spaceflight and has enough patience. The teacher clearly was not patient enough and had no idea how to explain these things to people who prefer reading Dostoyevski to reading Hawking.
If your country is not a space power, it also doesn't help, because the topic of spaceflight hardly ever appears in the media.
So it's not only about the educational system, it's about individual people and the overall attitude of the society.

[K-P]

any other suggestions for simple introductions to orbital dynamics/rocket science much appreciated.

I don't know about others but for me just playing with Orbiter Space Flight Simulator and flying around in near-Earth space with Delta Glider has been a true hands-on lesson of orbital mechanics. Taught even to me some new things about slingshots and orbital burns. And yes, landing on Venus... more like diving in an ocean.

(don't mean to promote/advertise anything, just enjoyed Orbiter)