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Comment Re:News from other countries... (Score 2) 19

Well, when it comes to space budgets....

NASA: $19,3B
ESA: $5,8B
Roscosmos: ~$2B/yr
JAXA: $2,0B
CNSA: $0,5B official / $1,3B est.
ISRO: $1,2B

It's not just US bias that leads to most stories coming from NASA. NASA really does spend the most on space research and exploration, by large margins.

Still, the public perception is that NASA's budget is far more than it actually is.

Submission + - Law for Autonomous Vehicles: Supporting an Aftermarket for Driving Computers (perens.com)

Bruce Perens writes: How will we buy self-driving cars, and how will we keep them running as self-driving software and hardware becomes obsolete much more rapidly than the vehicle itself? Boalt Hall legal professor Lothar Determann and Open Source Evangelist Bruce Perens are publishing an article in the prestigious Berkeley Technology Law Journal on how the law and markets might support an aftermarket for self-driving computers, rather than having the manufacturer lock them down or sell driving as a service rather than selling cars. The preprint is available to read now, and discusses how an Open Car, based on Open Standards and an Open Market, but not necessarily Open Source, can drive prices down and quality up over non-competitive manufacturer lock-in.

Comment Re:IT is amazing (Score 3, Informative) 90

Most folks drink stale coffee. Try roasting your own (I use Sweet Maria's for supplies) or going somewhere with a roaster on site who is honest enough to tell you the roast date. It should be from 2 to 10 days ago. Flavor development in coffee is a rancidification process. Like cheese, you want to catch it when it is a little, but not too, rancid.

Comment Re:...Or Just Take Aspirin. (Score 2) 90

Let's not forget the effect of helicobacter pylori bacteria on ulcers, they are in general held to be the main cause these days.

I have another theory about the beneficial effect of aspirin, caffine, etc. We evolved with them. Our diet was rich in salycilates and chemicals similar to theobromine or caffine. They came from the plants we ate, some of which were mildly toxic and which we evolved to process to the point that we became dependent on some of their effects. There are a lot of things in the primitive diet that modern people don't eat much at all, like acorns which had to be soaked to remove alkalai and tannin.

If this is the case, taking aspirin and drinking coffee or tea replace substances found in a more primitive diet.

Comment Re: Note that what's large... (Score 4, Informative) 76

Venus has multiple "tropopauses" and "stratospheres", depending on how you define them. The atmosphere is like a layer cake with multiple convection zones (like Earth's troposphere) separated by areas of dynamic stability (like Earth's stratosphere). And again, ~50-70km is an awfullly long way from the surface, and surface winds are weak. But, there's a lot about Venus that we don't understand.

Comment Note that what's large... (Score 3, Informative) 76

.... is the size, not the intensity. The air moves only slightly faster or slower than the surrounding atmosphere as one passes through the wave.

They weren't expected on Venus, though. Venus's surface is dozens of kilometers down, thick and "soupy" there, transitioning to thinner layers above. It was surprising to see that surface features that far away, in a fluid that can compress, would still make clear phenomena like gravity waves in the high atmosphere.

Comment Re: Not really needed for drones (Score 1) 24

Modulation designators that state the payload type don't make much sense with digital data transports. You can do digital TV or anything else with 4 MHz bandwidth. Cellular doesn't make much sense unless they have a really long hover time and drone life, in which case it could be a pop-up base station.

Comment Am I the only one... (Score 5, Interesting) 129

.... who can't help but cheer at my screen when they nail one of those landings? Now I finally understand how sports fans feel when they watch a game and do the same thing ;)

One thing nobody can deny about them is optimism. ;) Seriously, their IPS numbers are, pardon the pun, out of this world. $200k per booster launch. $500k per tanker launch. I mean, really? Good luck with that. No, seriously, good luck with that; I won't be expecting anything close to that, but please by all means prove me wrong ;) ITS would be a great system to have, I've been playing around with some Venus trajectories with it recently. Looks like it can do a low-energy transit with nearly 300 tonnes of payload from LEO and back again with the same, over 400 if starting at a high orbit - but from an economics perspective the high energy transfers actually make more sense.

I noticed a lot of people were confused about why Musk wanted the trips to be so short and was willing to sacrifice so much payload to do so - many assumed it had to do with radiation or something. But the issue is, when your craft costs so much but your launch costs are cheap, you can't have it spending all of its time drifting in deep space, you need to get it back for a new mission as soon as possible. There's a balancing point, in that if you try to go too fast, you reduce useful payload below the point of making up for it with going faster - but a minimum energy trajectory is just not optimal when the ratio between launch costs and transit vehicle cost is so extreme. I come up with the same thing from Venus as they were getting for Mars, although for the Venus case you end up aerobraking to a highly elliptical orbit rather than to the surface for ISRU refill (you need ISRU, but for the ascent stages, so it's not realistic to do so for the return stage in the nearer term). So for Venus they get no refill like on Mars, but they also don't have to do a powered landing nor do an ascent on return - it's six of one, half a dozen of the other. Both are quite accessible with it.

Comment Re:Great strides (Score 1) 129

It depends what you mean by "refurbishing"; each element is different.

The solid rocket boosters, for example, suffered a hard impact into salt water. They then had to be fished out of the water. And of course you don't just "refill" a SRB, they have to be taken apart and recast, then put back together.

The ET is disposable, and had to be rebuilt from scratch.

The orbiter was legitimately reusable, but with design flaws.

I don't blame the shuttle program - they were sort of pigeonholed into this dead end by circumstances. The concept came about during the heyday of the Apollo Programme, when NASA budgets were serious. It was supposed to be a much more reusable, much more maintainable, and somewhat smaller system. It was supposed to then have a huge flight rate supporting all of these big projects that were on NASA's docket, including a permanent moon base and a huge manned orbital station dwarfing ISS, which was supposed to replace Skylab.

But of course, Vietnam and the realities of having soundly trounced the USSR in the space race led to their budgets being slashed, which pushed the program into ever more untenable positions until it was nothing more than a jobs programme. Forget full flyback reusability of all parts. Forget the titanium frame for the shuttle, which would have let it run hot and thus not required so sensitive of a TPS. Go begging for money and be forced to modify the design to meet Air Force requirements, pushing you into an inferior design position. On and on.

If I'd fault them for anything, it'd be for going straight for a full reusable workhorse rather than a small-scale pilot programme first. But those were the days of optimism. Optimism which only recently seems to start being regained.

Either way, the Falcon boosters are a very different beast. A vertical soft landing is hugely different from the SRBs, yet the thermal issues are far easier than with the Shuttle. And the Merlins were designed from the start under the principle of preventing the need for a full teardown. That doesn't mean that they will be cheap to reuse. But it does mean that they have the possibility of it.

I do think SpaceX had a rather clever strategy, in that while their goal was reusable, they made a rocket that in the process was cheap as a disposable. So they could get volume and flight history while working on getting the kinks out. They may have flown too close to the sun with the densified propellants and (externally) unlined COPVs, but obviously, with a company like this, their whole existence is to push the envelope.

Comment Re: Awesome (Score 3, Insightful) 129

Most of Europe agrees with you. And even the US agrees with you up through high school plus with various forms of assistance for college, including state-subsidies, particularly for state colleges, and federal subsidies (direct subsidies, tax credits, and tax breaks), roughly $80B/year each. Pell grants alone cost the government $35B.

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