If you are not following the ambitious space program being undertaken by SpaceX, you are missing out on what is by far the most exciting thing happening in the world today. It's got everything - a visionary fearless leader with an ongoing record of accomplishments that has defied skeptics at every turn; increasingly routine rocket launches; spacecraft; billions of dollars in contracts; radical technological revolutions in rocket technology and economy every few years; and big plans including the human colonization of Mars. I had written a detailed primer on all of this in October - Why SpaceX is The Most Awesomely Awesome Thing Ever - so you may want to review that if you're not familiar and want to know more.
But just a few days ago, on Dec. 17th, SpaceX laid down another brick on the road to a limitless future with a low-altitude test flight of its Grasshopper test rocket: A 10-story tall Falcon 9 first stage standing upright on legs. The launch occurred to an altitude of about 40 meters, and then the gigantic thing came back down and landed - a type of flight fraught with perilous complexity even with small test rockets the size of Volkswagens, let alone something the size of a high-rise apartment building. An explanation of the significance of the flight and videos of the Awesome below.
The reason for Grasshopper's existence is the pursuit of something called reusability - as the term implies, it refers to the ability of a rocket to be recovered and flown again. This is what spaceflight looks like in science fiction: Ships that takeoff, fly around in space, and land over and over - which is why they can have names, like Enterprise, as opposed to just numbers. In reality, nearly all rockets from the beginning of the First Space Age have been "expendable": In order to conserve the amount of mass that has to be lofted into orbit, rockets don't carry the hardware needed to land back on Earth, and most are not even recoverable - they are just dumped into the atmosphere, and whatever is not pulverized by reentry sinks to the ocean floor.
To put this in perspective, this is tens of millions of dollars and up to a year of construction and testing just thrown away on a single flight, never to be recovered: A huge, almost terminal drain on the economics of spaceflight that would most likely keep humanity bound to Earth forever if it could not be overcome. Even if the economy of the whole world were mobilized and massively invested in pursuing it, as long as rockets remain expendable, the results would be pitiful: Over several decades of such investment, we might be able to sustain a few hundred people on the Moon and a few dozen on Mars with constant resupply shipments at enormous cost. Any global or even regional catastrophe on Earth would interrupt this supply chain and endanger the survival of these installations, and any disaster on the Moon or Mars that even partly destroyed its infrastructure and population would send trillions of dollars and decades of effort up in smoke.
But most likely the world wouldn't bother even trying at that cost: Humanity would retreat from space and spiral downward into itself until either we ourselves or some natural event ends us. The initial stages of that grim death spiral had already been unfolding before SpaceX came on the scene, and have been ever since the end of Apollo: NASA people who tried to commercialize their brilliant engineering ideas proved incompetent in business; the big aerospace companies with the money to bring new technologies to market in an economical way were too comfortable with their revenue streams to risk their own money on any of it, and stopped changing; and NASA itself (or at least the manned spaceflight side of it) was eaten away by the cancer of pork-barrel politics until that became nearly its only function, with an endless series of million-dollar paper studies and PowerPoint presentations taking the place of real spacecraft and exploration missions.
The picture today would be grim indeed if SpaceX were not doing what it's doing: The Space Shuttle - which was a failed attempt at reusability, sabotaged largely by political demands placed on its design and manufacturing that ended up making it far more expensive than expendable launches - was retired in 2011, leaving the United States without an independent manned spaceflight capability. Meanwhile, the Russian launch infrastructure which we are forced to depend upon to keep reaching the space station continues to decay, its work force to retire, and its reliability to consequently decline. The only other new entrant into the manned spaceflight arena, China, would eventually face the same erosive pressures as the US and Russia, and would never tolerate the kind of technological insurgency being waged by SpaceX on the part of its domestic companies. Basically, without SpaceX, humanity would be screwed.
So what it's doing is trying to pursue the ability to have rocket stages that reignite after separation and land themselves back on the launch pad, where they can then go through a quick and dirty touch-up and refueling and then launch again without compromising reliability. These are the rockets of science fiction: The rockets of Robert Heinlein and Arthur C. Clarke, before the civilizations in them move on to warp drives and conquer the universe. And if SpaceX succeeds in making this happen, according to Elon Musk, launches to Earth orbit will cost a hundredth of what they presently do: Meaning the cost of a ticket to orbit would be the cost of a car, not the cost of a car dealership. That's huge.
The first step to achieving this is to make the first stage reusable - this is the stage that takes the rocket off the pad and gets it up to a certainty velocity and altitude before separating, and it's the largest and most massive stage on a rocket. In the case of the Falcon 9 rocket, the first stage has 9 engines beneath the fuel tank, but SpaceX is starting more simply by designing Grasshopper to have only one engine. Obviously the stage will need to have landing legs, so Grasshopper has those too. And what they're doing with the testing of this rocket is going up to higher and higher altitudes, with longer rocket burns, and then landing back on the pad. The first test launch was just a little upward bounce of a little less than 2 meters, the second was to 5 meters, but now they've gone up 40 meters (131 feet). Eventually, pending FAA permits, they will launch it to high altitudes to simulate an actual first stage launch and landing.
Now for the awesomeness. This is by far the largest rocket ever launched and landed like this - almost three times taller than the famous DC-X whose cancellation was emblematic of NASA's tragic impotence and abandonment of technological development. It is huge compared to other test rockets being launched and landed vertically by other companies - almost all of which can be worked on upright by people standing on foot stools and little step ladders (Blue Origin's rocket is not small, but Grasshopper is still much larger). In other words, it is the only such system designed to be directly applicable to orbital spaceflight. Just for fun and to give a sense of scale, SpaceX put a 6-ft cowboy mannequin on the landing gear to show how huge this rocket is:
Now even with that image, you might not fully appreciate the size of this thing. So here it is in flight - the little speck on top of the landing gear rig is the cowboy:
And now the awesomeness in motion - see if you can spot the cowboy, and also note the buildings and communications towers below on the ground and how small they look beside Grasshopper:
Thanks for the Xmas gift, SpaceX!