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Comment Re:About time! (Score 5, Insightful) 392

are black holes really still considered theoretical constructs? ... I thought many scientific articles bring up black holes now and then without questioning, anyway.

Black holes do have a solid foundation in theory, and we can observe the gravitational effects they have on their neighbours. However, as far as I know, Hawking radiation is the only way to detect them directly and I don't think that this has been observed.

The authors of this article are showing observational evidence for a supermassive (millions of solar masses) black hole in the centre of our Galaxy - something that was thought to be at the centre of many galaxies but was still in open question. The observations made during this study have shown that our Galaxy has one, using techniques that are not an option for galaxies further away, thus giving us the best evidence that supermassive black holes exist.

Comment Re:Scary stuff (Score 5, Insightful) 486

I'm not saying it shouldn't be done. I guess my point is that the Millenium Bridge is so simple by comparison, yet it needed ~2 years of repairs after opening because of a wobble. People could have been thrown into the Thames, but no big deal, I guess. The space elevator, however, seems so much more prone to failure and with much bigger consequences.

Comment Re:Reverse Ray Tracing (Score 4, Informative) 98

We would need monumentally large telescopes for this. The largest optical telescope on earth, the Keck, has a diameter of 10m. Using the Rayleigh Criterion, we can calculate the minimum resolvable detail at a given distance. For example, we can resolve details on the surface of the moon (in the visible) that are around ~20 meters across. If you want to resolve an apple falling on somebodies head you need ~10 cm resolution. So to see this happening on the moon we would need a telescope with a primary mirror ~ 2.6 km across. To see the same thing echoed back from a dust cloud near the closest star to our sun (4 ly * 2), you would need a telescope with a primary ~ 7e+10 m across or around half the distance between the earth and the sun. Not to mention that the signal would be very weak and completely lost in noise.

Feed Science Daily: Some Biofuels Are Worse Environmentally Than Fossil Fuels, Analysis Shows (sciencedaily.com)

Biofuels reduce greenhouse-gas emissions in comparison to fossil fuels. In the journal Science, researchers consider environmental costs of biofuel production. Corn, soy and sugarcane come up short. The authors urge governments to be far more selective about which biofuels they support, as not all are more environmentally friendly than fossil fuels.

Feed Science Daily: Big Pharma Spends More On Advertising Than Research And Development, Study Finds (feedburner.com)

A new study estimates the U.S. pharmaceutical industry spends almost twice as much on promotion as it does on research and development, contrary to the industry's claim. The U.S. pharmaceutical industry spent 24.4% of the sales dollar in 2004 on promotion, versus 13.4% for research and development, as a percentage of US domestic sales of US$235.4 billion. The study's findings supports the position that the U.S. pharmaceutical industry is marketing-driven and challenges the perception of a research-driven, life-saving, pharmaceutical industry.


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It was pity stayed his hand. "Pity I don't have any more bullets," thought Frito. -- _Bored_of_the_Rings_, a Harvard Lampoon parody of Tolkein

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