Quotulatiousness

December 30, 2015

Elon Musk, Jeff Bezos and the future of spaceflight

Filed under: Space, Technology, USA — Tags: , , , , , — Nicholas @ 02:00

Colby Cosh on the real significance of the private space companies’ successes:

The science fiction authors who originally imagined spaceflight thought it would be classically capitalistic in nature — a Wild West of chancers, gold-diggers, outlaws, and even slave-traders transposed to the skies. It ended up, in its first incarnation, being a government program. This had the merit of showing that some impossible technical problems could be solved if you threw near-infinite resources and human lives at them. But the money and will ran out before NASA got around to figuring out how to make orbital spaceflight truly routine. Reusable rockets are the important first step that NASA didn’t have time to try in the Golden Age, under the pressure of a “space race” between governments.

Musk and Bezos are trying, I think very consciously, to revive the public interest and inspiration that this race narrative once brought. When SpaceX stuck its landing this week, having previously had a couple of flops, Bezos tweeted “Welcome to the club!” Musk will not mind the cheap shot too much. Bezos is doing him a favour by making a game of it.

It is hard for us to feel passion about accounting, even when “accounting” translates to cheaper satellite technology that means subtle advances in science and cost cuts in earthbound communications tech. Anything you can turn into a mere clash of personalities will get the attention of journalists and readers more readily. Musk and Bezos are exploiting their position as two of the great stage characters of our day.

The benefit they’re really going for is to bring a slightly larger margin of the human neighbourhood within reach for spaceships assembled on orbital platforms — the only practical kind of spaceship, as it seems to have turned out. Routine orbital access means affordable space tourism; it means possible Mars missions predicated on traditional exploration/adventure motives; it means deeper scientific scrutiny and even commercial study of the Moon, the asteroids, perhaps the inner planets. It means space stations that aren’t just for handpicked careerist supermen.

It means — well, we don’t know, from this side of the future, what it means. Some grade-three kid out there may already have a “killer app” for reusable rockets that nobody has considered yet. (If the cost comes down far enough, are we certain rockets won’t re-emerge as a possibility for long-haul terrestrial travel? That’s another assumption of early SF we have discarded, perhaps carelessly!) But it is probably a good guess that the balletic SpaceX triumph will turn out, after the fact, to have been one of the biggest stories of 2015.

December 23, 2015

SpaceX Falcon 9 performs successful launch and controlled landing

Filed under: Business, Space, Technology — Tags: , , , — Nicholas @ 04:00

William Harwood reports for CBS News:

Making its first flight since a catastrophic launch failure last June, an upgraded, more powerful SpaceX Falcon 9 rocket roared to life and shot into space Monday, boosting 11 small Orbcomm data relay satellites into orbit in a major milestone for the California rocket builder.

In a significant space “first,” the Falcon 9’s first stage fell back into the atmosphere and pulled off a powered landing at the Cape Canaveral Air Force Station, settling to a smooth tail-first touchdown in a convincing demonstration of reusability, a key requirement for lowering commercial launch costs.

In a scene resembling a launch video running in reverse, the booster quickly dropped out of a cloudy sky atop a jet of flame from one of its Merlin 1D engines, heralded by twin sonic booms that rumbled across Florida’s Space Coast. Cheers erupted in company headquarters in Hawthorne, California, as the stage settled to a smooth touchdown.

In another first, the Falcon 9 used colder, denser-than-usual liquid oxygen and kerosene propellants, a significant upgrade allowing the booster’s nine first-stage engines to generate more power, increasing their combined liftoff thrust from 1.3 million pounds to 1.5 million, or 170,000 pounds of thrust per engine.

The launch, first-stage landing and satellite deployments all appeared to proceed without a hitch, a welcome success for a company returning to flight after a disheartening failure.

“Everything we’ve seen thus far in the mission appears to be perfect,” SpaceX founder Elon Musk said in a conference call with journalists. “The satellites were deployed right on target and the Falcon 9 booster came back and landed. Looks like almost dead center on the landing pad. … As far as we can see right now, it was absolutely perfect. We could not have asked for a better mission.”

December 9, 2015

SF “war in space” memes of improbability

Filed under: Books, Military, Space — Tags: , , — Nicholas @ 03:00

Charles Stross explains several SF novel shibboleths that make him want to hurl the book against the nearest wall, including so many “war in space” stories:

Newton’s Second Law, for dummies. E = 1/2 * (mv2) — it’s not just a good idea, it’s the law. Notice the huge distances I alluded to above? Well, to get between planet A and planet B in anything approximating reasonable human time spans, you need to go fast. And if you go fast, your velocity relative to the bodies around you is also high. In event of an inelastic collision the kinetic energy transfer is proportional to the square of your velocity; and this has drastic consequences for space ships. Suppose you’re in low Earth orbit and you hit a piece of space junk, for example a screw that’s fallen off someone else’s ship. It’s traveling in pretty much the same orbit as you, but inclined at 30 degrees. What happens? What happens is you get a happy fun experience much like being hit by a bullet from a high-calibre sniper’s rifle, because (I can’t be bothered to do the trig here) it’s packing a velocity component angled across your path at a goodly fraction of orbital velocity, and at orbital velocity a kilogram of water packs kinetic energy equal to about ten times its mass in exploding TNT.

You know what a high-speed car crash looks like, right? Space ships travel a lot faster than that: if they hit something, it’s going to be very messy indeed. And that’s at sluggish orbital velocities; if you starship is barreling along at about 85% of the speed of light general relativity has something to say on the subject and it’s kinetic energy is equal to about half it’s rest mass — the equivalent of a 10 megaton hydrogen bomb for every kilogram of hull weight. (The pilot’s space-suited body alone packs the energetic punch of a Peak Strangelove 1980s USA/USSR strategic nuclear exchange.)

Human bodies are basically squishy sacks of goopy grease and water emulsions held together by hydrogen bonds and disulphide bridges between protein molecules and glommed onto some big lumps of high-grade chalk. We evolved in a forgiving, water-dominated low-velocity world where evolution didn’t bequeath us nervous systems able to comprehend and deal with high energy interactions other than in an “ooh, that lightning bolt was close! Where’s cousin Ugg?” kind of way. We can’t even see objects that flash across our visual field in less than 50 milliseconds — a duration in which, at orbital velocity, an object will have travelled on the order of half a kilometer.

Intuition and high energy regimes: do the math, or your space combat will be a whole bundle of nope.

(Other related cognitive errors include but are not limited to: Napoleonic navies clashing in space and firing broadsides back and forth at one another’s line of battle … spaceships with continuous high acceleration fusion-powered motors or similar that don’t glow white-hot then melt because vacuum is an insulator and shedding that much heat is a hard engineering problem (hint: a 100 ton spaceship accelerating at 1g requires 1 megaJoule of thrust: using a photon rocket for maximum efficiency that’s going to require 3 x 1015 watts of juice going in, if it’s 99.9% effective at heat dissipation that means it’s racking up around three terawatt of leakage, and that’s equivalent to about 45 kilotons of nuclear explosions per minute of waste heat) … warships using active radar to hunt for one another (hint: active sensor reach is inversely proportional to the fourth power of the emission strength, passive sensors obey the inverse square law) … warships using stealth in space (hint: infrared emissions, second hint: the background temperature you want to avoid standing out against is 2.73 degrees Kelvin, i.e. liquid Helium temperature) …

Oh for fuck’s sake, don’t get me started on war in space, we’ll be here forever unless we just throw physics to the winds of fiction and delegate all our hand-waving to magic hyperspace or cyberspace technology or something.

October 2, 2015

Something to worry about – chances of a Kessler cascade

Filed under: Space — Tags: , , , — Nicholas @ 04:00

If you’re the worrying type, Charles Stross has a bit more for you to fit into your nightmares:

Today, the commercial exploitation of outer space appears to be a growth area. Barely a week goes by without a satellite launch somewhere on the planet. SpaceX has a gigantic order book and a contract to ferry astronauts to the ISS, probably starting in 2018; United Launch Alliance have a similar manned space taxi under development, and there are multiple competing projects under way to fill low earth orbit with constellations of hundreds of small data relay satellites to bring internet connectivity to the entire planet. For the first time since the 1960s it’s beginning to look as if human activity beyond low earth orbit is a distinct possibility within the next decade.

But there’s a fly in the ointment.

Kessler Syndrome, or collisional cascading, is a nightmare scenario for space activity. Proposed by NASA scientist Donald Kessler in 1978, it proposes that at a certain critical density, orbiting debris shed by satellites and launch vehicles will begin to impact on and shatter other satellites, producing a cascade of more debris, so that the probability of any given satellite being hit rises, leading to a chain reaction that effectively renders access to low earth orbit unacceptably hazardous.

This isn’t just fantasy. There are an estimated 300,000 pieces of debris already in orbit; a satellite is destroyed every year by an impact event. Even a fleck of shed paint a tenth of a millimeter across carries as much kinetic energy as a rifle bullet when it’s traveling at orbital velocity, and the majority of this crud is clustered in low orbit, with a secondary belt of bits in geosychronous orbit as well. The ISS carries patch kits in case of a micro-particle impact and periodically has to expend fuel to dodge dead satellites drifting into its orbit; on occasion the US space shuttles suffered windscreen impacts that necessitated ground repairs.

If a Kessler cascade erupts in low earth orbit, launching new satellites or manned spacecraft will become very hazardous, equivalent to running across a field under beaten fire from a machine gun with an infinite ammunition supply. Sooner or later you’ll be hit. And the debris stays in orbit for a very long time, typically years to decades (centuries or millennia for the particles in higher orbits).

How about a kickstarter campaign for laser-equipped orbit-cleaning satellites? Sweep up our orbital trash before it becomes a huge problem. If you’ve read Neal Stephenson’s Seveneves, you’ve already got the image of a really extreme result of too much space junk (in the case of the novel, it was shattered pieces of the moon creating the Kessler cascade).

November 13, 2014

Words you don’t expect to hear in the news: 67P/Churyumov-Gerasimenko

Filed under: Europe, Science, Space — Tags: , — Nicholas @ 00:03

European Space Agency fails to harpoon a comet … successfully lands anyway:

In 1998, the Hollywood blockbuster Armageddon asked us to believe that it was possible to land a spacecraft on an asteroid hurtling towards Earth — too far-fetched, right? Not so. Today humanity just achieved the seemingly impossible.

Earlier this afternoon, scientists from the European Space Agency’s (ESA) Rosetta mission successfully landed the unmanned Philae lander module on comet 67P/Churyumov-Gerasimenko. The complexities of this mission are such that a short article cannot do justice to the men and women who made this mission a success, but here are a few of the mind-boggling highlights:

The Rosetta probe launched in March 2004 after years of careful planning. Since then, it has travelled 6.4 billion kilometres through the solar system to get into the orbit of the comet 67p, which itself is just four kilometres in diameter. Comet 67p is orbiting the Sun at speeds of up to 135,000 kilometres per hour and is currently about 500 million kilometres from Earth. After a period during which it successfully orbited comet 67p, the 100 kilogram Philae lander then separated from the Rosetta orbiter, descended slowly and landed safely.

At the time of writing, the latest reports from the ESA suggest there may have been some problems with the lander’s anchoring mechanism. The lander was designed to fire harpoons into the surface of the comet to ensure it stayed in place — this may not have worked. But to be fair, no one has tried harpooning a comet before, so a few glitches are understandable.

Update: BBC News has more on the unexpectedly bumpy landing and the risk that the lander may not be able to stay active very long due to battery limitations. Having landed in the shadow of a cliff, the batteries are not able to be recharged by the solar panels.

The craggy surface of the comet - looking over one of Philae's feet

The craggy surface of the comet – looking over one of Philae’s feet

After two bounces, the first one about 1km back out into space, the lander settled in the shadow of a cliff, 1km from its target site.

It may be problematic to get enough sunlight to charge its batteries.

Launched in 2004, the European Space Agency (Esa) mission hopes to learn about the origins of our Solar System.

It has already sent back the first images ever taken on the surface of a comet.

Esa’s Rosetta satellite carried Philae on a 10-year, 6.4 billion-km (4bn-mile) journey to Comet 67P/Churyumov-Gerasimenko, which reached its climax on Wednesday.

After showing an image that indicates Philae’s location — on the far side of a large crater that was considered but rejected as a landing site — the head of the lander team Dr Stefan Ulamec said: “We could be somewhere in the rim of this crater, which could explain this bizarre… orientation that you have seen.”

Figuring out the orientation and location is a difficult task, he said.

“I can’t really give you much more than you interpret yourself from looking at these beautiful images.”

But the team is continuing to receive “great data” from several different instruments on board Philae.

Another problem with the lander — aside from not knowing exactly where it landed — is that one of the landing legs isn’t actually in contact with the surface:

Controllers re-established radio communication with the probe on cue on Thursday after a scheduled break, and began pulling of the new pictures.

These show the feet of the lander and the wider cometscape. One of the three feet is not in contact with the ground.

Philae is stable now, but there is still concern about the longer-term situation because the probe is not properly anchored — the harpoons that should have hooked it into the surface did not fire on contact. Neither did its feet screws get any purchase.

Lander project manager Stephan Ulamec told the BBC that he was very wary of now commanding the harpoons to fire, as this could throw Philae back off into space.

He also has worries about drilling into the comet to get samples for analysis because this too could affect the overall stability of the lander.

“We are still not anchored,” he said. “We are sitting with the weight of the lander somehow on the comet. We are pretty sure where we landed the first time, and then we made quite a leap. Some people say it is in the order of 1 km high.

“And then we had another small leap, and now we are sitting there, and transmitting, and everything else is something we have to start understanding and keep interpreting.”

Photo of the comet's surface from about 40 metres as the lander made its initial descent.

Photo of the comet’s surface from about 40 metres as the lander made its initial descent.

October 18, 2014

Unmanned X-37B returns to earth after nearly two years in orbit

Filed under: Space, Technology, USA — Tags: , , — Nicholas @ 11:50

In the Telegraph, Rob Crilly tells us what is known about the X-37B’s mission:

It arrived back at a California air base after dark. Only the eagle-eyed would have spotted the snub-nosed spacecraft gliding out of the black sky.

Officially, the unmanned Boeing-built X-37B Orbital Test Vehicle had just completed its longest ever mission, spending almost two years circling the Earth, conducting experiments.

But its secretive history has sparked countless theories about what the computer controlled craft was really doing in space.

One idea is that the US Air Force has developed a drone spy ship, which it uses to shadow Chinese satellites. Another more fanciful claim is that it has been developed to engage in sat-napping — gobbling up rival spy satellites like something from a James Bond film.

There were few clues in an official press release.

“The landing of OTV-3 marks a hallmark event for the program,” said an unidentified programme manager quoted in the Air Force statement.

“The mission is our longest to date and we’re pleased with the incremental progress we’ve seen in our testing of the reusable space plane. The dedication and hard work by the entire team has made us extremely proud.”

September 6, 2014

P.J. O’Rourke on what’s wrong with modern rocket ships

Filed under: Humour, Space, Technology — Tags: , — Nicholas @ 12:10

From his post at The Daily Beast:

I was in the passenger seat of a small rocket ship when I realized what’s wrong space travel these days: I can’t do it yet. I’m still flying on pokey old Boeings for six hours from Boston to LA. The trip would take 15 minutes at 17,500 mph low earth orbit speed.

Also, rocket ships don’t fly. Or they don’t properly fly the way the rocket ships of Buck Rogers and Captain Video did. Buck and the Captain could use a hayfield with a windsock. A modern rocket blast-off produces so much shockwave commotion that the nearest safe viewpoint at Cape Canaveral is eight miles from the launch pad. That puts the Starbucks a long way from the gate when your rocket ship’s final boarding announcement is made.

Plus current rockets lack anything resembling Buck Rogers’ style. They look like evil corn silos or upright storm sewers or a trio of escaped steroidal church organ pipes wearing party hats.

Furthermore, at the moment, there’s no such thing as a small rocket ship.

The first rocket to reach space, the Nazi V-2 (which transported people only in the sense of transporting them to the next life) was 45 feet high and weighed 27,600 pounds. The 363-foot Saturn V used for the Apollo moon landing was 52 feet taller than the Statue of Liberty and almost 15 times her weight. And Lady L, tipping the scales at 225 tons, is no Mary-Kate Olsen. Now NASA is building a new Space Launch System (SLS) that’s even bigger.

All my rocket ship disappointments are the result of there not being enough private companies like XCOR Aerospace. I learned this at the Space Foundation’s annual Colorado Springs Space Symposium exhibit hall, where there was a full-scale mock-up of XCOR’s Lynx that I sat in.

The Lynx’s 30-foot fuselage and 24-foot wingspan would fit in a McMansion garage. And it’s as prettier than anything a rich car collector has in there now.

May 25, 2014

Russian rocket export ban means increasing opportunities for private enterprise in space

Filed under: Russia, Space, Technology, USA — Tags: , , , , — Nicholas @ 09:46

Strategy Page looks at the knock-on effects of the Russian government banning the export of rocket engines to the United States:

The U.S. government is being forced to use satellite launchers developed without government financing because the usual methods of obtaining these launchers is falling apart and currently is unable to supply enough rockets to get all American military satellites into orbit. The immediate cause of this problem is the recent (since earlier this year) Russian aggression against Ukraine. The U.S. responded to this aggression by placing sanctions on some Russian officials and firms. Russia responded to that by halting RD-180 shipments to the United States. That’s breach of contract and it will do enormous damage to Russian exports in the future because now many countries and firms realize that a contract with a Russian firm can be cancelled by the Russian government for any reason. This was always seen as a risk when doing business with Russia and many Western firms declined to do so or have pulled out of Russia in the last decade because of the growing unreliability of Russia as a business partner. The RD-180 affair got a lot of publicity, all of it bad with regard to future Russian exports of high-end industrial items. Europe, which gets about a third of its natural gas from Russia, is already looking for alternate sources and investors are fleeing Russia (and taking their money with them).

[…]

This is good news for the new private firms that are developing rockets for launching stuff into orbit. One such firm is SpaceX (Space Exploration Technologies Corporation) and is has been trying to break the current cartel controlling U.S. government satellite launch services. Since 2006 all this business has gone to a government-approved monopoly called the ULA (United Launch Alliance) which is composed of Lockheed Martin (Atlas 5 rocket) and Boeing (Delta 4). These two firms have dominated U.S. space launches for over half a century. Because of the RD-180 the Atlas 5 is more attractive (in terms of performance and price) than the Delta 4. Meanwhile SpaceX expects to have Atlas 5 competitor ready in a few years.

In 2012 SpaceX obtained its first contract to launch U.S. military cargo into space. SpaceX had earlier obtained a NASA contract which included 12 deliveries to the International Space Station (at $134 million each). What makes all this so noteworthy is that SpaceX developed its own launch rockets without any government help. SpaceX also developed the Dragon space vehicle, for delivering personnel and supplies to the International Space Station.

SpaceX has since proved that its rockets work and is pointing out that the SpaceX rockets can do the job cheaper that ULA. Currently ULA gets a billion dollar a year subsidy from the government that SpaceX would not require. SpaceX still has to get all the paperwork and approvals done so that they can handle classified missions. SpaceX does not see this as a problem, it’s simply going to take another year to satisfy all the bureaucrats and regulations.

May 1, 2014

SpaceX and the successful re-entry experiment

Filed under: Space, Technology — Tags: , , , , — Nicholas @ 07:58

Amanda Wills talks about the most recent SpaceX achievement:

When SpaceX launched its Dragon supply mission to the International Space Station on April 18, it tried something revolutionary after the spacecraft was safely in orbit.

Behind the scenes, CEO Elon Musk and his team had been testing the reusability of this rocket. On that Friday, the team returned part of it to Earth for the first time in history. Once Dragon was in space, the first stage separated and re-entered Earth’s atmosphere. As the helium-filled rocket slowed, it extended four 25-foot-long landing legs and used its thrusters to briefly hover over the Atlantic Ocean before plopping down ever so gently onto its surface.

Musk and his team pulled it off — a huge feat considering that the chance of success was only around 30% to 40%. The SpaceX team recovered the raw video from the camera that was on board Falcon 9, and software engineers have spent the last week trying to repair the footage, which was taken just before splashdown.

[…]

The team was able to bring back the first stage. The rocket was clearly vertical — an important detail in testing reusable rockets — and the soft landing was successful. However, the weather wasn’t cooperative that day and the stage was destroyed by rough waves. Fortunately, Musk said his team was able to recover bits of the rocket.

April 19, 2014

ISS resupply mission successfully launched

Filed under: Space — Tags: , , , — Nicholas @ 09:45

And another story from yesterday that I would have covered:

SpaceX shoots off the launch pad right on time

SpaceX shoots off the launch pad right on time

The Falcon 9 rocket lifted off from Cape Canaveral on schedule at 12:35pm PDT (8:35pm UTC), carrying 5,000 pounds of supplies for the ISS. The first stage separated cleanly two minutes and fifty one seconds into the flight, 103km above the launch pad, and the Dragon capsule has deployed its solar panels and is now on course to dock with the ISS in two days, once orbital paths have matched up.

It was a very close run thing. The CRS-3 mission was due to take off on Tuesday but was cancelled after a helium leak was detected. Friday’s launch was much tighter, and SpaceX said the launch had a one-second window if the rocket was to successfully insert its cargo into the right orbital plane.

Weather was a big worry for the SpaceX team. There was rain and relatively heavy clouds at the launch site, and the team floated multiple weather balloons into the upper atmosphere to make sure that winds weren’t too strong at altitude.

Unfortunately, the heavy winds and storm conditions in the Atlantic may hamper the second part of Friday’s mission: the remote landing of the first stage of the Falcon 9 rocket. After separating, the booster is planned to fire up again and slow down, falling back towards the Earth.

If all goes well, the rocket will then deploy four legs, which were covered for the initial launch phase, and begin a controlled burn to slowly sink towards the ocean and hover for landing and retrieval. At least, that was the plan.

But the inclement weather means the SpaceX support ship that was due to witness the rocket’s return and retrieve the hardware couldn’t get into position. SpaceX says it will attempt the soft landing anyway, but there’s no word yet on its success or otherwise.

April 14, 2014

SpaceX to test hover capability on next launch

Filed under: Space, Technology — Tags: , , , — Nicholas @ 08:25

In The Register, Brid-Aine Parnell explains what will be different about the next SpaceX launch to resupply the ISS:

NASA has said that SpaceX’s latest cargoship launch to the International Space Station will go ahead, despite a critical computer outage on the station, allowing the firm to test the craft’s hovering abilities.

[…]

The booster rocket that’s blasting the Dragon supply capsule into space is going to attempt to make a hovering soft landing after it’s disengaged and dropped back to Earth.

The spruced-up Falcon 9 has its own landing legs, which Elon Musk’s space tech company hopes will eventually make for precise set-downs on the surface of alien worlds. For this test though, the rocket will still be coming down over the ocean, just in case.

The launch is already a month late with its nearly 5,000 pounds of supplies and payloads, including VEGGIE, a new unit capable of growing salad vegetables for the ‘nauts to munch on. The ship was delayed from March after a ground-based radar system at Cape Canaveral was damaged.

July 28, 2013

Let’s go on a shuttle ride … on the outside of the booster

Filed under: Space, Technology, USA — Tags: , — Nicholas @ 10:37

Published on 15 Mar 2012

From the upcoming Special Edition Ascent: Commemorating Space Shuttle DVD/BluRay by NASA/Glenn a movie from the point of view of the Solid Rocket Booster with sound mixing and enhancement done by the folks at Skywalker Sound. The sound is all from the camera microphones and not fake or replaced with foley artist sound. The Skywalker sound folks just helped bring it out and make it more audible.

H/T to Anthony Watts for the link.

November 24, 2012

Tim Worstall: Cosmic fun-spoiler

Filed under: Economics, Space, Technology — Tags: , , , — Nicholas @ 11:42

Writing in The Register, Tim Worstall brings his evil economist gaze to the SF fan’s irrational belief that asteroid mining is the way of the future:

Isn’t it exciting that Planetary Resources is going to jet off and mine the asteroids? This is every teenage sci-fi geek’s dream, that everything we imbibed from Verne through Heinlein to Pournelle is going to come true!

But there’s always someone, isn’t there, someone like me, ready to spoil the party. The bit that I cannot get my head around is the economics of it: specifically, the economics of the mining itself.

In terms of the basic processing of what they want to do I can’t see a problem at all, just as all those authors those years ago could see how it could be done.

Asteroids come in several flavours, and the two we’re interested in here are the ice ones and the nickel iron ones. The icy rocks, with a few solar panels and that very bright 24/7 sunshine up there, can provide water. That’s the first thing we need in abundance if we’re going to get any number of people up off the planet for any appreciable amount of time. And we’d really rather not be sending the stuff up out of the Earth’s gravity well for them.

It’s also true that those nickel iron asteroids are likely to be rich in platinum-group metals (PGMs). They too can be refined with a bit of electricity, and they’re sufficiently valuable (say, for platinum, $60m a tonne, just as a number to use among friends) that we might be able to finance everything we’re trying to do by doing so.

All terribly exciting, all very space cadet, enough to bring tears to the eyes of anyone who ever learnt how to use a slide rule and, as the man said, once you’re in orbit you’re not halfway to the Moon, you’re halfway to anywhere.

Except I’m not sure that the numbers quite stack up here. I’m sure that the engineering is possible, I’m certain that it’s all worth doing and most certainly believe that we want to get up there and start playing around with other parts of the cosmos over and above Gaia. But, but…

November 19, 2012

Space-Age technology on Earth, but not so much in space

Filed under: Science, Space, Technology — Tags: , , , , — Nicholas @ 09:33

In The Register, Shaun Dormon explains why almost all the electronic components used on modern spacecraft, satellites, and the International Space Station (ISS) are actually not cutting-edge, top-of-the-line items:

I hate to say it, but most of what you think about space-age technology is a total fabrication. It’s the stuff of sci-fi.

Perhaps the biggest misconception of all is that spacecraft are equipped with cutting-edge computing platforms that any self-respecting technophile would commit unspeakable acts to get their mitts on.

If only. The fact of the matter is that even the most advanced chips up there were considered obsolete ten years ago down here. Although it’s true that in space no one can hear you scream, outer space is actually a very noisy place, electromagnetically speaking.

The computer on your desk is very unlikely to experience much in the way of EM radiation unless someone cuts a hole in the side of the kitchen microwave. Out in orbit, though, there are many sources of radiation, ranging from the relatively mundane stuff pouring out of the Sun and collecting in the Van-Allen radiation belts to more exotic things such as cosmic rays and other high-energy particles that cause so-called “single-event effects”.

[. . .]

The damage is cumulative. Individually, an impact causes the ionisation of a single oxide molecule present in the semiconductor. It’s not enough to cause instant failure, but as more and more impacts take place, the effects combine to significantly alter the electrical properties of the circuit until it can no longer function correctly.

More exciting dangers arise from exposure to gamma or cosmic rays. These ultra-high energy impacts cause localised ionisation which results in an unexpected flow of current. In the case of a lower energy event, this may result in a “single event upset” or “bit-flip”, and data corruption can ensue. These are not usually fatal to the system. No so the worst case “single event burnout”, which creates such high currents that the very circuitry itself is burned out almost instantaneously.

October 29, 2012

The Dragon returns, bearing cargo

Filed under: Business, Space, Technology — Tags: , , , , — Nicholas @ 09:37

At The Register, Brid-Aine Parnell reports on the mostly successful cargo delivery round-trip by SpaceX’s Dragon capsule:

The reusable cargoship dropped into the ocean yesterday evening around 250 miles off the coast of Mexico after resupplying the ISS and its crew. The Dragon was ferried to a port near Los Angeles where it will be prepped for its return to SpaceX’s test facility in Texas.

Some of the cargo brought back by the capsule is due to be returned to NASA in the next couple of days, including research samples from the station’s microgravity environment. The ship delivered 882 pounds of gear to the ISS, including scientific research and crew supplies. It returned with nearly twice that weight of stuff.

The mission was only a part-success, as the secondary objective was to launch a satellite for Orbcomm, but due to a malfunctioning engine in the launch phase, the satellite could not be placed in the correct orbit and was lost. Orbcomm is sticking with SpaceX for two more satellite launches in spite of this initial failure.

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