how are we going to get into space cheaply in the future?

[imported_Technomancer]

Originally posted by: VigilanteCS
Maybe solar sails?

That's fine if you like getting them ripped to shreds by dust/debris or other spaceborne material. They won't turn very well, and can only generally accelerate in one direction: away from the nearest most-significant radiating body.

One issue for escaping Earth gravity is the friction of air. Eliminate the friction, or at least substantially reduce it, and access to LEO and UEO is improved. Last I read, Russian scientists have claimed to develop a plasma that can eliminate this friction and eliminate sonic booms, radio waves, etc for a low constant input of energy on the order of single-digit watts for the Su-37.

The issue for anti-matter is concerning, but it requires much more research. It may be feaseable however; we wouldn't need very much, and it is actually everywhere, if not as constantly as normal matter due to the constant interactions of appearance/annihilation with their respective anti-particles. This is actually one line of thought that has led to what some have termed "zero-point energy" but there is too little trustworthy information there to be useful to us for space-travel.

One other method that I have never seen discussed would be to NOT move the vehicle per-se, but to move the space-time in which that vehicle occupies. For proof of this, just see our own universe, many parts expanding faster than nominal lightspeed. However, this is also unrealistic as a short-term goal, probably even near-term.


All this speculation does lead to one conclusion however; what we need for ideal space access in general has these qualities:

Access space cheaply
Quick transportation in Earth orbit
Quick transportation throughout Sol system
Plentiful fuel and resources for maintenance
"Easy" maintenance and precautions; it must be possible to repair vital vehicle systems in-flight or execute countermeasures to ensure surviveability without requiring extensive communication with "ground control"
Surviveability of human occupants; radiation, food, water, heat,
"gravity" to prevent atrophy for extended periods in space
Ability to traverse various types of space "terrain" such as flares and extreme radiation, high-velocity objects, and land in various types of climates/weather intact.

Each of these must be worked on and completed to the extent that it can be mass-replicated cheaply by the private sector.

 

[Calin]

A huge solar sail (several square kilometers or several square miles) will give you a "thrust" of several newtons (or tens of newtons). You can't use this as long as you are in any kind of atmosphere at all. You can only use them once you are in orbit (be it even low earth orbit).

You must take into account that 90% of the mass of the atmosphere is lower than 10km. At sea level you are limited by lots of things - like meteorological situation, maybe rain and so on, things that disappear once you go above 10 miles high.
Looking once more, the SRB jettison at a height of 26 mautical miles or almost 50km. Not many craft would be able to raise a significant payload at that altitude... Especially at the speed of 4,600 km/h that is attained after the solid rocket boosters separate from the shuttle.

 

[Tenshodo]

I think future spae explorations will be performered by multi stage rockets. The first stage could be performed using Proabably a chmical burn or something could ferry it to high altitudes. the second stage at high altidues or even in space could be performed using aerospike engines
http://www.aerospaceweb.org/design/aerospike/main.shtml theoretically these have excellent efficiancey at low athmosphere conditions.

After in space, thrust could be perfromed using anti-matter engines. Anti matter is still controversial and it is difficult to create However.it is 100 % efficiant allowing for small amounts to create huge amounts of power through anhihalation. My theory is that, we can huge magnetic feids to shape the anti matter in the direction we want it to and expose it to matter such as a gas. for a comparison- modern Nukes are about 10 -20 % efficiant meaning only 10-20 % of their mass is converted into energy, now multiply that numer by 5 or 10 and see the damage from that amount of antimatter more info here http://en.wikipedia.org/wiki/Antimatter

that or we can perfect fusion which we are already making great leaps in- http://www-pub.iaea.org/MTCD/NF/NFusion.asp
http://www.ipp.mpg.de/~Wolfgang.Suttrop/ppcfsites.html

Other forms of power include nuculear batteries whoicih has great potnetial- http://www.spectrum.ieee.org/WEBONLY/publicfeature/sep04/0904nuc.html

One last controversial power is Zero Point enrgywhichi s basically a theory of huge amounts of power in a very small space- http://www.zpenergy.com/

Im just giving my opiniosns on this

 

[Valkerie]

Originally posted by: Soldier
I see no alternative to chemical energy rockets any time soon. Space planes sound good but they have been talked about for decades and no one has one yet so there must be issues unresolved. Ion drives can be deployed once in space to allow long journeys but time frames quickly reach decades and centuries if your looking at anything outside the solar system. Nuclear holds a lot of promise but political BS will most likely keep it from ever being put to use.

highly agree

The United States respectively has one of the most advanced space programs in the world, NASA as well as its taggers. In fact the Air Force is weighing this issue as well, how to crack the atmosphere with planes and what not.

 

[Vee]

Originally posted by: unipidity
Hmm. Height can only really be that big an advantage because it allows lower frictional losses. I mean that change in energy from sea level to 40,000ft isnt that big.

Yes, friction, AND shockwave energy losses can be lessened, and is quite a big deal.
But what both you and Calin miss is the effect on rocket engine efficiency. A rocket engine can be designed to be more efficient, the less static pressure it is designed to operate in. These effects snowballs (the rocket will have to carry its own fuel and so on), so again it's a big deal. High altitude is definitely worthwhile for exactly the same reason that makes it so hard to fly at.

(BTW, the standard launch vehicle for the Pegasus is a Lockheed Tristar.)