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Comment Re:No KSP at SpaceX? (Score 4, Informative) 213

Firstly, I think SpaceX were trying to get away from parachute recoveries. The Shuttle solid booster rockets used to parachute down into the ocean, but the problem with that is that they need completely cleaning out and refurbishing between each flight.

Secondly, they would need more than parachutes to recover the first stage because it is travelling so fast when it separates (not sure of the exact number, but somewhere between 2 and 4 Kilometers per second). They have to do a retrograde burn to slow down enough to safely re-enter the atmosphere.

Submission + - Earth Gets Another Quasi-Moon 1

The Bad Astronomer writes: Astronomers have found a new asteroid, 2014 OL339, that is a quasi-moon of the Earth. Discovered accidentally earlier this year, the 150-meter asteroid has an orbit that is more elliptical than Earth's, but has a period of almost exactly one year. It isn't bound to Earth like a real moon, but displays apparent motion as if it did, making it one of several known quasi-moons.

Comment Re:Old git speaking here... (Score 1) 942

The thing is, I'm not sure the vast majority of people do still use those imperial units. UK schools have taught in metric units for the last 40 years, and all food and drink (with the exception of draught beer and cider) has had to sold with metric labelling for the last 20 years. I'm 41, and although I have a good idea of what an inch and a foot is, I have no particularly intuitive feeling for a pound or an ounce, so I always have to the mental conversion to grams or kilograms first, and I grew up at a time when imperial measured labelling was more common.

Comment Re:This is not government policy (Score 1) 942

The thing I find interesting is that David Cameron is probably among the last set of people in the UK to have been taught any imperial measures in school - in fact he would have been eight years old in 1974 when using metric units in schools became compulsory, so it's possible he could have been taught both imperial and metric (Unless private schools were exempt from such rules, I guess).

Certainly anyone aged 44 or under in the UK will have grown up with the metric system in school.

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.

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