Quotulatiousness

October 23, 2011

DARPA’s new project: space vampires

Filed under: Military, Space — Tags: , , , — Nicholas @ 12:04

Yep. DARPA is hoping to release “swarming robot space vampires”* in geosynchronous orbit:

More than $300 billion worth of satellites are estimated to be in the geosynchronous orbit (GEO—22,000 miles above the earth). Many of these satellites have been retired due to normal end of useful life, obsolescence or failure; yet many still have valuable components, such as antennas, that could last much longer than the life of the satellite. When satellites in GEO “retire,” they are put into a GEO disposal or “graveyard” orbit. That graveyard potentially holds tens to more than a hundred retired satellites that have components that could be repurposed — with the willing knowledge and sanction of the satellite’s owner. Today, DoD deploys new, replacement satellites at high cost — one of the primary drivers of the high cost is the launch costs, which is dependent on the weight and volume of antennas. The repurposing of existing, retired antennas from the graveyard represents a potential for significant cost savings.

DARPA’s Phoenix program seeks to develop technologies to cooperatively harvest and re-use valuable components from retired, nonworking satellites in GEO and demonstrate the ability to create new space systems at greatly reduced cost. “If this program is successful, space debris becomes space resource,” said DARPA Director, Regina E. Dugan.

[. . .]

“Satellites in GEO are not designed to be disassembled or repaired, so it’s not a matter of simply removing some nuts and bolts,” said David Barnhart, DARPA program manager. “This requires new remote imaging and robotics technology and special tools to grip, cut, and modify complex systems, since existing joints are usually molded or welded. Another challenge is developing new remote operating procedures to hold two parts together so a third robotic ‘hand’ can join them with a third part, such as a fastener, all in zero gravity. For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Legos at the same time while looking through a telescope.”

* “Swarming robot space vampires”, courtesy of jwz.org.

July 25, 2011

Unique view of the shuttle cockpit

Filed under: Space, Technology, USA — Tags: , , — Nicholas @ 10:05


Click to embiggen

Link provided by Chris Greaves.

Update: There’s a big comment on this shuttle post from Chris Taylor, discussing what the shuttle was originally intended to be, and why it ended up being significantly larger and more expensive than the first proposal.

July 24, 2011

Farewell Space Shuttle . . . you massive boondoggle

Filed under: Bureaucracy, Space, Technology — Tags: , , , — Nicholas @ 12:25

I’ve been ambivalent about the space shuttle program for decades — not because I’m anti-space, but because I think the shuttle was government methadone to replace a real space program. At that, I hadn’t connected all the dots the way Scott Locklin has here:

The Space Shuttle, an object lesson in the Sunk Cost Fallacy, has been with us since my early youth. This preposterous boondoggle was originally supposed to make manned space flight cheaper: to the point where getting a pound of matter into space would be as cheap as sending it to Australia. That was the only purpose for building the damn thing in the first place. The idea was, if your spaceship was reusable, it would be cheaper to send people and heavy things into space. If using the same thing multiple times isn’t cheaper, well, what’s the point? Conspicuous consumption, perhaps?

In one of its original incarnations, the Shuttle was supposed to launch like an ordinary aircraft. A jet + rocket powered “first stage” heavy lifter would propel the craft into the upper atmosphere, and the rocket propelled second stage would send the thing into space. Seems like a good idea to me. Jets are pretty easy to fly and maintain cheaply. Jets also don’t have to carry vast quantities of oxidizer. Plus; you get to reuse the whole mess.

Unfortunately, the politicians decided that building the first stage heavy lifter would cost “too much.” Instead they changed the design, and strapped a couple of solid rockets to a beefed up “orbiter” and giant non-reusable fuel tank. That wasn’t the worst of it: those pieces should have still in principle provided for a cheap launch vehicle. In practice, the silica tiles and engines turned out to have very high maintenance costs involving substantial labor, and turn around times were 1/6 of what they should have been, making the thing 6 (though more like 10) times as expensive as it was designed to be.

The goal of the space shuttle program was to have safe, re-usable spacecraft that could lift heavy loads to low earth orbit at a cost of about $50 per pound. What they ended up with was a dangerous fleet of hangar queens that took loads to orbit at an estimated cost of $50,000 per pound. That’s quite a missed set of goals.

May 30, 2011

NASA’s changing goals for Orion

Filed under: Politics, Space, USA — Tags: , , , , — Nicholas @ 09:56

The ever-sarcastic Lewis Page looks at how NASA has been trying to reposition their planned Orion spaceship:

NASA has declared that its pork-tastic Orion moonship — whose primary mission disappeared with President Obama’s decision that there will be no manned US return to the Moon — is now to be a “deep space transportation system”, suggesting that the agency plans to send it on missions beyond Earth orbit.

It remains unclear how the newly-renamed Multi Purpose Crew Vehicle (MPCV) will travel into space, when it will do so and what its destination might be — though a near-Earth asteroid is a likely possibility. A major reason for Orion’s continued survival appears to be ignoble porkbarrel politics — but there is a tantalising possibility that it might fly beyond Earth orbit in the relatively near future.

What Page calls NASA’s “pork map” shows why the MPCV has strong, bi-partisan political support regardless of its actual utility for the space program:

Regardless of the political support, however, the most likely view of US federal government finances indicates that Orion/MPCV won’t be viable in the proposed timeframe. There’s a non-governmental choice, however:

Famous geekbiz-kingpin Elon Musk and his upstart rocket company SpaceX have come from nowhere in just eight years to successfully test-fly their brand new and very cheap Falcon 9 rocket and Dragon capsule, already apparently quite capable of performing the ISS supply mission. Only a few years ago, many in NASA and the established industry were arguing that this would never happen.

It’s also no secret that Musk and SpaceX are working on a new Merlin 2 rocket engine, much bigger than the current Merlin 1 which propels the Falcon 9. A multicore heavy lifter based on Merlin 2 would be in the 100-tonne-plus realm required to mount a Mars mission, and will surely be the cheapest offering competing at the 2015 heavy lift Mars-rocket decision.

May 24, 2011

Britain’s entry in the new race to space

Filed under: Britain, Space, Technology — Tags: , , — Nicholas @ 09:12

Jonathan Amos reports on the UK Space Agency (UKSA) long-simmered design/proposal called Skylon:

Skylon has been in development in the UK in various guises for nearly 30 years.

It is an evolution of an idea first pursued by British Aerospace and Rolls Royce in the 1980s.

That concept, known as Hotol, did have technical weaknesses that eventually led the aerospace companies to end their involvement.

But the engineers behind the project continued to refine their thinking and they are now working independently on a much-updated vehicle in a company called Reaction Engines Limited (REL).

Realising the Sabre propulsion system is essential to the success of the project.

The engine would burn hydrogen and oxygen to provide thrust — but in the lower atmosphere this oxygen would be taken directly from the air.

This means the 84m-long spaceplane can fly lighter from the outset with a higher thrust-to-weight ratio, enabling it to make a single leap to orbit, rather than using and dumping propellant stages on the ascent — as is the case with current expendable rockets.

Update: Lewis Page has more on the Skylon project.

December 9, 2010

A step closer to private space travel

Filed under: Space, Technology — Tags: , , , , , , — Nicholas @ 00:01

SpaceX’s Dragon capsule was successfully launched into orbit:

Judging by the excited faces of SpaceX employees after the live webcast, everything went perfectly. Dragon, the world’s first orbital space capsule built by the private sector, will now orbit the planet a few times over the next couple of hours before splashing down in the Pacific.

It is a small but significant milestone. The unmanned demonstration mission wants to prove that Dragon is able to deliver crew and cargo to the International Space Station (ISS). The reason for all the excitement is that the working capsule really points the world firmly in the direction of greater involvement by the private sector in providing trips to space. More competition means lower prices. Lower prices mean better access. After the retirement of the shuttle, Dragon would be able to deliver crew and cargo to the ISS on top of a Falcon 9 rocket.

Here’s hoping that NASA won’t succeed in choking off/crowding out other private launch efforts.

More information (including some graphics) at the BBC website.

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