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Space

New Class of Stars Are Totally Metal, Says Astrophysicist 119

Posted by samzenpus
from the hit-the-lights dept.
KentuckyFC writes Stars form when clouds of gas and dust collapse under their own gravity, generating enough heat and pressure to fuse the atoms inside them together. When this cloud of dust and gas is the remnants of a supernova, it can contain all kinds of heavy elements in addition to primordial hydrogen, helium and lithium. Now one astrophysicist has calculated that a recently discovered phenomenon of turbulence, called preferential concentration, can profoundly alter star formation. He points out that turbulence is essentially vortices rotating on many scales of time and space. On certain scales, the inertial forces these eddies create can push heavy particles into the calmer space between the vortices, thereby increasing their concentration. In giant clouds of interstellar gas, this concentrates heavy elements, increasing their gravitational field, attracting more mass and so on. The result is the formation of a star that is made entirely of heavy elements rather than primordial ones. Astrophysicists call the amount of heavy elements in a star its "metallicity". Including preferential concentration in the standard model of star formation leads to the prediction that 1 in 10,000 stars should be totally metal. Now the race is on to find the first of this new class of entirely metal stars.

Comment: Once past 50, you're fucked. (Score 2) 370

by caferace (#47292597) Attached to: Age Discrimination In the Tech Industry
I'm feeling this. I worked for Netscape back in the 90's. I'm considerig trimming that from my resume simply because it make me look too old-school. There is definite discrimination amongst up and coming companies. It's incredibly frustrating for me, a guy in his early 50's. I know a metric shit-ton of stuff, and especially the shortest path to get to the goal. Do I get hired, or even a reply on sending in a resume? No. My long work history stretching back to 1983 has me handcuffed.

Comment: Re:I've got a great idea! (Score 1) 89

by BZ (#47291339) Attached to: Mozilla Is Working On a Firefox OS-powered Streaming Stick

Mac OS supports shipping both 32-bit and 64-bit binaries in a single executable. That's what Firefox on Mac does.

That _is_ a viable solution on Windows, albeit with multiple executables, but it about doubles the size of the download. Unfortunately, Windows users are very sensitive to the download size for their web browsers; past experiments have shown uptake dropping rapidly as the download size increases.

Comment: Basically a toy (Score 1) 85

by GlobalEcho (#47251607) Attached to: Shawn Raymond's Tandem Bike is Shorter Than Yours (Video)

As a "real" tandem person (see here), I must say this thing looks like a toy to me. Of course, it is also far less expensive than the bikes made by serious tandem bike companies, who often make bikes with derailer and brake systems that alone cost as much as this monstrosity.

We've had our tandem going 60-70mph (down mountain roads). There's no way I would trust this thing for such riding. Maybe it is OK for some gentle cruises, but that's it. And furthermore, there's a far better design for front-stoker visibility.

/snob mode off

Comment: Table salt (Score 1) 82

by GlobalEcho (#47211661) Attached to: Biodegradable Fibers As Strong As Steel Made From Wood Cellulose

replacement for many filament materials made today from imperishable substances such as fiberglass, plastic, and metal. And all this from a substance that requires only water, wood cellulose, and common table salt to create it

I would hate to be the poor bastard in the factory whose job it is to stand there shaking the salt cellar all day.

Comment: Entering students too young (Score 4, Insightful) 325

by GlobalEcho (#47181149) Attached to: Fixing the Humanities Ph.D.

The median time to get a Ph.D. is nine years.

I think students who enter are often doing so by default. Education has been their life unto that point, they have always been outstanding students, and they enjoy it. They are too young and inexperienced to realize how long 9 years is and what they'll be missing (or perhaps they are too optimistic about their personal chances of being an outlier).

Comment: Re:Frequent auctions (Score 1) 382

by GlobalEcho (#47176549) Attached to: High Frequency Trading and Finance's Race To Irrelevance

defeating the HFTs basically comes down to adding a delay to multi-exchange transactions such that the transaction reaches each exchange at the same time.

Budish shows in his paper how that is not true. Basically, it works only if very little of the total volume is on a delayed exchange.

The stock exchanges are engaged in the same sort of crap with the HFTs, selling them special access and trade types that other investors do not have.

I don't see a problem with that. Back in the old days of floor trading, the floor traders had special access everyone else lacked. And they behaved very badly compared to what we now see with HFTs.

If our regulatory agencies were more competent, this would have been dealt with years ago instead of letting it fester as long as it has.

They are careful, not incompetent. The gut reaction of lots of people is that any middleman is a parasite. The reaction in the American West to the rise of hardware and lumber specialists during the late 19th century (fueled by general stores) is an excellent example with similar popular political outrage behind it. I'm glad the regulators did nothing about it.

Comment: Frequent auctions (Score 1) 382

by GlobalEcho (#47175199) Attached to: High Frequency Trading and Finance's Race To Irrelevance

For those of you not frothing at the mount, Eric Budish has an interesting critique and proposal to replace continuous-time markets with auctions every second or so. The idea is that being forced to wait for the next auction mitigates the advantages of low-latency trading.

I think he makes a very good argument.

Comment: Nanoseconds (Score 5, Interesting) 137

by GlobalEcho (#47031713) Attached to: Grace Hopper, UNIVAC, and the First Programming Language

My mother was one of the first female programmers at Honeywell back in the `70s. Back then, IT companies recruited their programmers from the ranks of mathematicians (like mom).

Grace Hopper was a big hero to her, and one of the things I remember best is mom coming home with a short length of wire given out by Adm. Hopper at a speech -- sized to represent the distance electricity would travel in a nanosecond.

Mom is still coding, by the way, writing custom software for my dad's business in Python/Django/PostgreSQL. Dad complains that she's obsessed with the programming and won't do anything else. Sounds like me...thanks for the genes, mom!

Comment: Re:Explanation of Mozilla (Score 4, Insightful) 403

You're mischaracterizing Brendan's position on DRM, as I'm sure he would tell you if you just asked him personally. I strongly recommend you do so.

He doesn't like DRM, and neither does anyone else at Mozilla, but you do realize that he was CTO and then CEO while most of the negotiations with Adobe were happening, right?

A meeting is an event at which the minutes are kept and the hours are lost.

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