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SpaceX Unveils Heavy-Lift Rocket Designs
FleaPlus writes "At the recent Joint Propulsion Conference, SpaceX's rocket development facility director Tom Markusic unveiled conceptual plans for how its current Falcon 1 and Falcon 9 commercial rockets can be evolved into heavy-lift rockets, ranging from a Falcon X capable of lifting 38,000kg to orbit, up to a 140,000kg Falcon XX (more than either the Saturn V or the 75,000kg shuttle-derived rocket Congress currently plans on having NASA spend >$13B building). SpaceX presentations also discuss a new Merlin 2 heavy-lift engine, solar-electric cargo tugs, adapting their current engines for descent/ascent vehicles fueled by Mars-derived methane, and a desire for the government to take the lead on in-space nuclear thermal propulsion while commercial focuses on launchers. In a recent interview, SpaceX CEO/CTO Elon Musk expressed his goal of lowering the price of Mars transportation enough to enable early colonization in 20 years, and his own plans for retiring to Mars."
I like nuclear thermal as much as the next /.er, but is there really any point in thermal rockets beyond attaining orbit?
For one thing there's the slight problem that you die during the transit through the Van Allen belts if you don't have a high-thrust engine or very large radiation shields.
And nuclear thermal rockets kind of suck ass for attaining orbit since you have to ensure that they land somewhere safe if they fail during launch; NASA's test plans for the early models involved polar launch where the flight path was designed to dump it in Antarctica or a remote part of the ocean if something went wrong.
As 0123456 indicated, there are both a need for high thrust engines in space and huge risks with the use of nuclear-anything propulsion on Earth. In addition to passage through the Van Allen belts, we also need to consider the Oberth effect. When you're trying to leave a gravity well (such as Earth's), then thrust deep in the well has a higher effective ISP than equivalent thrust higher up the well.
Second, because of the risks of operating nuclear rockets in Earth's biosphere, it makes sense, that if you're eventually going to have a nuclear powered rocket to orbit, that you try it somewhere else first and generate a reliability record. Space is the "somewhere else".
For space exploration to begin in earnest, we need it to be economically profitable, beyond LOE and geostationary. Has there been a study on the economic feasability of mining asteroids or something else (i.e. 4He on the moon)?
Yes, and as I understand it, the problem is that costs are a few zeroes greater than revenue. Something like SpaceX's new rocket can lop a zero off the costs, but we're going to need more than that before space mining makes economic sense. If they can lop off a second zero, say via high reusability and a launch rate of thousands of rockets a year, that might do.
I applaud the Obama administration for recognizing the awesomeness and redirecting funds from NASA Ares to Space-X.
Quick clarification: The White House hasn't proposed redirecting funds from Ares to SpaceX -- instead, they want to open up the US human spaceflight market to competing commercial vendors, which includes not just SpaceX, but also the United Launch Alliance. Many aren't familiar with the name, but the ULA builds the Atlas and Delta rockets which have launched most national security and NASA science missions for many years now. SpaceX has stated that they actually expect ULA to get more of the commercial crew market than them, at least initially.
Of course, even this is facing a great deal of friction in Congress. As one of the linked articles in the summary states, the current NASA bill in the House of Representatives has the entire commercial spaceflight program struggling with just $150M over 3 years, while the government-designed/operated heavy-lift and crew capsule program gets $13B over that same timeframe.
However, there is one key thing that SpaceX needs as they develop as a company. First, and foremost, SpaceX needs to get its LEO business to become lucrative and profitable. If that company can develop enough profit to start breaking away from NASA prize money and other political tie-ins, then they will be set.
Not sure if you already knew about this, but back in June SpaceX announced a huge launch contract with Iridium, which is the largest commercial launch contract in history (worth up to $492M). Of course, more contracts like that would be better, but change happens a step at a time.
It is actually reworked Kipling.
When you're wounded and left on Afghanistan's plains
And the women come out to cut up your remains
Roll onto your rifle and blow out your brains
and go to your God like a soldier.
Your "fair share" is NOT in my wallet.