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Spectrum of Light Captured From Distant World 32

An anonymous reader writes with this excerpt from Cosmos: "Astronomers have made the first direct capture of a spectrum of light from a planet outside the Solar System and are deciphering its composition. The light was snared from a giant planet that orbits a bright young star called HR 8799 about 130 light-years from Earth, said the European Southern Observatory (ESO). ... The find is important, because hidden within a light spectrum are clues about the relative amounts of different elements in the planet's atmosphere. 'The features observed in the spectrum are not compatible with current theoretical models,' said co-author Wolfgang Brandner. 'We need to take into account a more detailed description of the atmospheric dust clouds, or accept that the atmosphere has a different chemical composition from that previously assumed.' The result represents a milestone in the search for life elsewhere in the universe, said the ESO. Until now, astronomers have been able to get only an indirect light sample from an exoplanet, as worlds beyond our Solar System are called. They do this by measuring the spectrum of a star twice — while an orbiting exoplanet passes near to the front of it, and again while the planet is directly behind it. The planet's spectrum is thus calculated by subtracting one light sample from another."

Comment Not a Big Problem. (Score 5, Informative) 263

I wouldn't raise alarm too much, cosmic rays affect a space craft in mainly three ways: Single Even Upset (SEU), Single Event Latchup (SEL), and Total Ionization Dose (TID) measured in kRad. The higher cosmic rays increase the TID, but all these satellites are built for it and it shouldn't raise an alarm except for very long term missions. SEUs and SELs are what the phrase "just one cosmic ray could disable unlucky satellites or even put a mission to Mars in jeopardy." is mentioning. SEUs aren't too much too worry about, usually nothing too harmful, just a few errors and at worst a reset of some subsystems. The bad one is the SELs. These can cause a temporary short and potentially cause damage. The key thing with SEUs and SELs is that they're typically temporary and the spacecraft's power systems nowadays can easily handle them. The solid state switches/fuses they started with Cassini (and are now typical for NASA missions) are very effective (accidently proven so during integration) and can cut off a shorted subsystem quite fast and prevent damage.

In a nutshell, don't get your panties in a bunch.

Comment Good Idea (Score 1) 176

Here at Penn State several of the electrical engineering professors use IBM tablets. They're nice and tiny, last all day, and are possibly the best teaching tool I've come across. I personally own a Toshiba tablet, and while it was pretty good for a while, the hardware has failed constantly. The support was pretty good, but the computer is struggling now that the 3 year warranty is up (dead accelerometer, pen pressure sensitivity not working, screen is wobbly, fixed the CD-ROM myself). I've heard a lot of good things about the IBM models, namely the x61 I believe.

My one tip? For God's sake, don't be that teacher that sits through class endlessly trying to figure out how to use it. Don't introduce it into your classroom until you have the routine down. I had one professor that decided to use it for a signals and systems review, and at least half the time spent was him trying to figure out how to use the computer. He was more of a side walk chalk on the board kind of guy...


Submission + - Software piracy by country

UnHolier than ever writes: A short article and interesting graph from the Economist. "America and China lead the world in terms of total losses from piracy at $7.2 billion and $5.4 billion respectively. But when calculated according to the number of computers in each country a different picture emerges. Cash-strapped countries dominate the leader board. In Azerbaijan, which comes out on top, computers are loaded with $262-worth of pirated software on average. But Iceland is the surprise second-placed nation" with about $220/computer.

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