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Submission + - New Mars crater spotted in before-and-after pictures

The Bad Astronomer writes: The Mars Reconnaissance Orbiter spotted a new crater on the surface of Mars, and, using before-and-after pictures, the impact date has been nailed down to less than a day — it happened on or about March 27, 2012. The crater is 50 meters or so in size, and surrounded by smaller craters that may have been caused by smaller impacts due to the incoming meteoroid breaking up. Several landslides were spotted in the area as well, possibly due to the shock wave of the impact.

Comment Re:I don't like the control it takes away from you (Score 1) 865

Personally, I'm neutral. On one hand, the Prius and Nissan keyfobs that just sit in a pocket are cool with one less thing to flip open. On the other hand, having to stick the physical key in the vehicle with a very low power transmitter handling the passive anti-theft access gives a bump in security.

There's no transmitter in my key. You're thinking of the RFID keys, which are pretty good security: coupled with a decent quality alarm with multiple immobilizers it makes a car pretty much unstealable unless you have a flatbed.

But there's no reason you can't simply put the RFID into the alarm keyfob instead of the key. In fact, most of the pushbutton starters I've seen in recent years work exactly like that -- there's an RFID in your keyfob, and if you don't have the keyfob in your pocket (or within a few feet of the car), the car simply won't start. If the car gets out of range of the keyfob, it'll trip the fuel line immobilizer.

Comment England is pretty bright (Score 1) 55

Looking at the map in the UK, the vast majority of England is coded yellow or worse (5.6 - 6.0 - suburban sky). In some places you can can get green coded (6.1 - 6.5 - suburban / rural transition), and there's only four areas coded blue (6.6 - 7.0, rural), which are along the border with Scotland, a chunk of Cornwall, a very small bit of the North Norfolk coast at Wells-next-the-sea, and a bit at the border with Wales. Wales in general fares better with some proper dark places through the central and western of the country, as does Scotland in the highlands and along the border with England. Northern Ireland has a few spots of 'blue' in the north and southwest of the country.

Anyway, for me a it's a little disappointing - It'd be many hours drive to get to anywhere rated 'blue' or darker, and over an hour to get to the only place in the whole of the southeast rated 'green'.

Submission + - Astronomers determine the length of day of an exoplanet

The Bad Astronomer writes: Astronomers have just announced that the exoplanet Beta Pic b — a 10-Jupiter-mass world 60 light years away -— rotates in about 8 hours. Using a high-resolution spectrometer and exploiting the Doppler shift of light seen as the planet spins, they measured its rotation velocity as 28,000 mph. Making reasonable assumptions about the planet's size, that gives the length of its day. This is the first time such a measurement has been achieved for an exoplanet.

Comment Re:Hybrids, diesel and Prius (Score 1) 93

Modern car diesels are just under 40% efficient. The biggest diesel ship engines can just make 50% efficiency.
The current Prius petrol engine is 38.5% and the next model will be over 40%. Petrol engines are making good progress in efficiency, diesel engines less so.

A ship engine isn't a fixed RPM diesel generator, it's a variable RPM diesel engine.

What I was talking about, you need to be comparing against a diesel-oil power plant, which can exceed 70-80% efficiency. Still not as good as hydroelectric (which can exceed 95%), but aside from tidal and hydro power plants it's by far the most efficient method of generating energy that we have. It's also worth mentioning that a diesel engine can run on basically unmodified cooking oil (look up biodiesel). I sincerely doubt that your Prius would enjoy being fed that stuff.

Submission + - Astronomer discovers nearby brown dwarf literally as cold as ice

The Bad Astronomer writes: Using data from the orbiting WISE and Spitzer infrared space telescopes, an astronomer has discovered a brown dwarf that is just 7.2 light years away, making it the seventh closest known interstellar object to the Sun. Not only that, it's cold ; its temperature is likely 240-260 Kelvin, well below the freezing point of water. It's literally as cold as ice.

Comment Re:Efficiency (Score 2) 93

A fixed RPM diesel is *significantly* more efficient than a car engine, on the whole. We're still not approaching the 90% that GP quotes as the efficiency for an electric, but it's enough of an improvement to still waste less energy despite the losses inherent in transmission lines.

The long-distance transmission of energy, incidentally, is where the real loss in the electrical grid comes into play. That's not really an issue when you're talking about hybrid drive vehicles. Still, I've wondered for years why car manufacturers don't design a pure electric car (plug-in), and fit it with a fixed RPM generator for extended range instead of trying to design a hugely convoluted hybrid drive train that can receive power from both. (and no, Top Gear doesn't count).

Submission + - Earth-sized planet discovered in its star's habitable zone

The Bad Astronomer writes: Astronomers have announced the discovery of Kepler-186f, a very nearly Earth-sized planet in its star's habitable zone. The planet is the fifth in a system of five orbiting a red dwarf star 500 light years away, and is located in the region where liquid water could exist on its surface. It's not know if this planet is Earth-like — that is, with water and air and the potential for life — but it's the closest we've yet seen where one could be like our own planet.

Comment Re:Modern audiophiles are no different. (Score 1) 469

Can you explain this? I would have thought the signal would remain digital and at its original sampling rate.

It's the encoding that the HDMI decoding device supports. It does support uncompressed stereo PCM audio in the spec, but most devices will use some form of compression in the transmission, in order to reencode it as DTS or Dolby Digital for your receiver. A lot of devices do this by default, without user input, if they're connected to a receiver that can handle more audio channels. While this can usually be disabled/reconfigured, a lot of users won't actually think about that.

Case in point -- I'm watching an MKV on my WDTV Live! as I type this. I ripped the DVD myself, and know for a fact that the audio channel I'm listening to right now is AC3 stereo (though the file does have an English-language 5.1 channel). The stereo's surround sound/5.1 light is active. The device is upmixing the audio to 5.1 surround before it's sending it to the receiver.

Comment Re:Modern audiophiles are no different. (Score 0) 469

With a sufficiently high bitrate, and a detailed enough codec, you may as well not be compressing it.

The problem with the comparison between an MP3 and something encoded with FLAC is that you're still working off a digital source. By its very nature, the digital source is lossy -- it's limited by the original sample and bitrate. You can offset that by using a high enough resolution on the digital source, but ultimately, there's still going to be loss of information, no matter how high a resolution you use for the source.

As for audiophiles, I identify as one. I do prefer FLAC for archiving purposes, because I'm not hurting for space, and because it allows for a much higher bitrate than MP3 (and my stereo plays FLAC natively), but I will also qualify it with what I consider a far more important distinction : you will get *much* more mileage out of a good set of speakers than you will from going with FLAC over MP3. There is absolutely no reason at all to go with FLAC over MP3 if you don't have hardware that can take advantage of it. If you're listening to it mostly on a cell phone with shitty ear buds, then there is absolutely no reason to waste space on a high resolution recording. Similarly, if you don't have a stereo that can play FLAC natively (since even passing the sound over an HDMI link will cause the signal to be degraded), and you're not pairing it with good quality speakers, then it's a total waste of space. And no. That $1000 set of speakers you bought at Best Buy is *not* a good quality set of speakers. That's not even close to high end, when it comes to audio hardware.

Submission + - Object seen in skydiver's helmetcam unlikely to be a meteorite 3

The Bad Astronomer writes: The viral video showing what looked like a meteorite falling past a skydiver made quite a splash, with many people assuming it was true. However, further analysis shows that it's also perfectly consistent with being a small (1-3 cm) rock that fell out of the parachute itself, which is a far more likely explanation.

Comment Re:Ummm, probably not (Score 1) 142

That analysis was done here: http://norskmeteornettverk.no/... (it's not in English, but google translate does a decent job). He makes a distance estimate based on speed, which itself is based on the assumption it's a falling rock at terminal velocity. But the distance, speed, and time it takes to cross the FOV are related, and if you make a stab at speed you can get distance and vice versa.

Comment Re:Ummm, probably not (Score 1) 142

Yes, the apparent speed is the biggest argument against it being something packed in the 'chute, I'd think. If the skydiver were still decelerating hard after the parachute opened, the rock could appear to move rapidly, but even then it appears to come from farther away than the parachute. I'm still looking into this, and will have my own thoughts posted tomorrow on my blog.

Comment Re:I think this is bullshit (Score 1) 1746

If someone said that in Alabama in 1957, would it be justified to deny them employment for the rest of their life even if they changed their mind after the Civil Rights Act passed?

I'm not denying him employment. I'm choosing to do business with a different company that has a better track record on issues that I consider important. There's an enormous difference. In this case, all 4 of the main companies competing against Mozilla's flagship product have better records on LGBT rights than Eich, and so I have chosen to do business with one of them instead.

Also, if Eich has changed his mind on gay marriage, he hasn't publicised it. Actually he's done quite the opposite, by publicly refusing to apologize for it. That refusal is, to me, tantamount to saying that he still believes that gay couples shouldn't have equal rights, which is a matter that affects me personally. If he chooses to ignore the writing on the wall and continue his opposition to equal rights, that is his choice to make. And if that choice makes him unemployable, he has nobody to blame but himself. Freedom of speech means he's free to be an asshole, it doesn't mean I have to do business with him despite his douchebaggery.

If it's not as important to you, that's your choice. But don't claim I'm discriminating against him, or being bigoted. I'm not. I'm just voting with my clock cycles and bits (since no money actually changes hands when I download/install another browser).

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