Not to be pedantic, but lasers most certainly have drop. In fact, the photons in a pulse of laser light fall towards the center of the Earth at exactly the same rate of acceleration as bullets do (namely 32 ft per second per second). It's just that they travel so fast, the transverse velocity they develop (v=gt) and distance off target that they move (d=1/d g t^2) during their short time of flight (t) are negligible.
Most of the depleting rotational energy of the Earth goes into the orbital energy of the moon, which means the moon will be boosted in its orbit and recede from Earth until the Earth is slowed down enough that the same side of the Earth faces the moon as it orbits ("tidally locked"). Which, by the way, is why the man in the moon always faces us (i.e. tidal locking happened long ago on the moon). At that point, a day and Earth an an orbit on the Moon would both last about 47 days. Estimates for when this would occur are around 50 billion years, by which time the sun will have swollen up in its death throes and consumed the Earth.
There is some heat generated due to friction from tides and distortions of the Earth's crust, but the rotational-orbital exchange is much more significant.
Here's your best and most direct path: use your IT skills to leverage an engineering job in the field. I have seen many technically inclined IT engineers and programmers take this route. Step-by-step:
Immediately: take an introductory astronomy course at a local community college or continuing education program at your local university to demonstrate your interest,
Then: assess your IT skills, and apply them directly to the support of an upcoming large ground- or space-based observatory. This is an especially sensible route if you do any database related work. The future of astronomy is big data and massive virtual observatories which collect together and make useful petabytes of information from a wide variety of facilities.
Check the job listings at the American Astronomical Society, looking in particular for IT support positions where your domain knowledge would outrank that of PhD-trained astronomers (who learn to program "on the job" and rarely master grittier back-end systems). Realize that almost all existing and (especially) new astronomical facilities have substantial IT/engineering staff, and that your skills do not exist among traditional PhD scientists. Example: the LSST will produce 30 TB of data per night, which needs to be processed in semi-real time. Example #2: the incredibly successful Sloan Digital Sky Survey partnered with Microsoft database engineers to build its (at the time) state-of-the-art public-facing data archive. The late Jim Gray was instrumental in building the Sloan backend, and said his favorite thing about astronomical data is that it was "worthless" (by which he meant the usual access control layers were not necessary, freeing him to focus on much more rewarding and useful tools).
Relocate to a mission control or operations center for the facility. These are often located at major research universities, or equivalent national facilities like the Space Telescope Science Institute in Baltimore, the National Radio Observatory in Charlottesville, VA, the Gemini Observatories (Hawaii/Tucson/Chile), etc. Advantage? You will very likely be immediately mixed in with groups of professional astronomers. You will be strongly encouraged to learn to speak their language, and to become more involved in the scientific aspects of the project. You will learn a great deal just through osmosis. You will likely be able to attend seminars, sit in on classes, bend the ear of willing faculty, etc. And the most significant advantage? You could be contributing directly to the forefront of astrophysics research within 3-5 years. Disadvantages: the pay might be somewhat less than similar background applied in the financial or health industries. Often the intellectual rewards bring talented engineers anyway. Also, may projects are time limited, so you positions are typically not permanent (but new projects are coming online all the time).
That is our bias, an observer's bias. For example, "Supernova 1987a" occurred in the Large Magellanic Cloud, a small dwarf galaxy orbiting the Milky Way, which is close to 170,000 light years away. So this star actually blew up just as the first modern Homo Sapiens began wandering around East Africa. Yet we call it "1987a".
And for good reason. Many of the supernova we routinely observe in the early universe are reaching us from across such great distances, that they happened well before the Sun and Earth even formed; many perhaps even before the Milky Way galaxy was meaningfully assembled.
I worked a summer as an engineering intern at the largest US manufacturer of breath-alcohol systems. There were dozens of models made to accommodate the wildly varying requirements among states and nations regarding what
false positive signals to "rule out". Basically, the systems were very simple infrared spectrometers, made to look for telltale absorption bands of the ethanol molecule in just a few (like 3-4) broad infrared wavelength bands (see e.g. here). The problem is, a large range of simple organic molecules absorb at similar wavelengths. So, for example, to rule out acetone (rotten fruit? nail polish remover?), you'd need to add one or more bands where the two molecules differed in absorption properties. And so on for other molecules with similar optical behavior. I believe the UK had the strongest requirements for ruling out false positives; something like a dozen channels were required (which increased cost, difficulty of calibration, and weight).
It's because implicit in this comparison is the statement "for a fixed field of view and resolution", which implies a focal length, and hence aperture size, which scale with with sensor size: See http://www.clarkvision.com/imagedetail/does.pixel.size.matter/#The_f_ratio_Myth. Large detectors are not intrinsically more sensitive, but for a given field of view and angular resolution, they collect more light than small sensors, going as the square of the its size.
All the scientists I know (myself included) would correctly indicate that the sun will not grow cold, but will, after exhausting its core hydrogen fuel, vastly increase its luminosity, and swell in size past the Earth's orbit, essentially vaporizing it. All this, in roughly 5 billion years.
Modern humans as a species are 0.0002 billion years old. Yes, that's three zeroes to the right of the decimal. Do you really believe that we'll care about a couple thousand years worth of exemplars of humanity after we've evolved 25,000 times further than since we separated from proto-human homonids? Will we even be humans at that point? Are there any other conceivable disasters our species or its descendants could suffer during those billions of years, which colonizing space could not prevent?
The article is wrong on many levels. The key word here is "direct". The 2002 transmission spectra you mention (and others like it) consist of light from the host star, passing through the atmosphere of the planet as it passes in front of it, which imprints spectral signatures of the planetary atmosphere on that stellar spectrum. So in this sense, its not a direct spectrum of the planet's own light, but of the star, modified by the planet in front of it.
The first spectrum of a planet, consisting only of planetary light, came from the Spitzer Space Telescope, which used a differencing technique:
planet + star [out of eclipse] - star [when planet eclipsed] = planet only
The star and planet could not be resolved (separated) by the telescope, but by using the known orbit of this eclipsing planetary system, and timing the observations carefully, a spectrum of the "planet's own light" was obtained.
The novelty of this latest result is that no differencing of this sort was required. Using adaptive optics to correct distortions due to Earth's atmosphere, the light from a star and the light from its associated giant planet where physically resolved, and a spectrum of the planet, all by itself, was obtained. Even with adaptive optics, however, very few systems have star-planet separations on the sky large enough to permit this technique.
I am a scientist, and work primarily in metric units. I can think equally comfortably of a mile or km, and acknowledge the many benefits of calculations performed in metric, and of celsius (or it's relative, Kelvin) as a temperature scale in the laboratory. Yet I cannot endorse the Celsius temperature scale for everyday use over Fahrenheit.
From one viewpoint, there is no fundamental difference between them. They scale linearly between two temperature points, assigning values of 0 and 100:
Celsius: [freezing point of water, boiling point of water]
Fahrenheit: [a cold solution of brine, human body temperature (approx)]
I argue that degrees F offers a more suitable range, and better resolution, than degrees C for temperatures encountered in everyday life. The smallest temperature difference I can detect? Roughly 1 degree F. That's 0.55 degree C. It's also why you often see forecasts in fractional degrees C. A day so cold you have to protect skin? 0 degrees F. A day so hot that wind actually warms you up? 100 degrees F. The advantages of Celsius in the lab are clear. For weather? Not so much.
You are close to correct. Some large number of joules of energy here on Earth arise from material leftover from supernova predating the sun: radioactive materials, which can be harvested directly in fission reactors, or indirectly through tapping the Earth's molten inner they help to heat. The Earth's internal heat also results not from the sun, but from the continued slow tapping of gravitational potential energy from the material from which the sun and its planets formed. This power source is roughly 40 TW, compared to the 100,000 TW of solar power reaching the Earth's surface. Still, several times the current worldwide energy consumption.
My car gets about 30 MPG and after a half hour 30 mile drive is thirsty for a gallon of gas. After a multi-hour 30 mile bike ride I am very hungry and can easily eat two pounds of food (and still lose weight, if it's salad and not eight quarter pounders with cheese and bacon). Anyway, that two pounds of food obviously takes twenty pounds of gasoline to grow and process and ship and cook. Now at 6 pounds of aviation gas per gallon (note I am not a pilot, but that is my fuzzy memory from wanting to be a pilot decades ago) that would make a bit over 3 gallons of gas to grow the food to bicycle 30 miles.
Your argument only works if you assume that otherwise you would not have consumed those 2lbs of food. Obesity-associated illness trends, in the USA at least, would indicate otherwise. By biking, you burn calories you would be eating anyway, improve your health, and save gas too.
When I had comcast and they began this bundling business some 5 years back, it was actually $3 cheaper to get the basic TV service with your internet than no service at all. When I pointed out the inanity to the customer service rep, they kept saying: "It's a package deal, like at McDonalds". To which I replied: "Yes, but since when is the cheeseburger more expensive than the happy meal?"
When I had comcast in AZ, I had internet-only service for a couple of years, $42/mo. Apparently, however, it was difficult to provide this without also providing unscrambled channel TV service. So they decided on the following scheme:
Internet alone: $62
Internet with Basic Cable TV (local only): $59
Yes, forgoing the TV would cost you 3 dollars. After an unproductive 10 minutes on the phone with Comcast, who kept insisting that this was a new Bundling deal that would save me money, I made the following analogy. Imagine if getting just the cheeseburger cost more than getting the whole happy-meal. She wasn't impressed.
All the concern about too many eggs in one basket is certainly valid. However, one major advantage of a centralized login system is being missed here: the ability to change all of one's password easily on a somewhat regular basis. As it stands now, I have so many accounts, many of which use the same password, some of which use variations of that password, etc., that the notion of going through and changing all those passwords is completely daunting. Hence, I never do it.
With openID, every time I got a bit nervous, I could change the one true password, and still have to remember only it. A good openID provider could even give reminders or enforce a password expiration, which would go from extreme nuisance when done on an individual site basis, to real additional security, potentially offsetting the loss of security inherent in the single point of failure for many users.
A University commissioned report on the effectiveness of the Australian gun buy-back program concluded as follows:
In 2007, researchers at the Australian National University reported "There were on average 250 fewer firearm deaths per year after the implementation of the National Firearms Agreement than would have been expected," Statistics are funny things.
That's a feature. The bookmarks pane has the semantics of any other page load, which to me is quite intuitive. You can open the bookmark view in a new tab by Apple-clicking the little book icon at the left of your bookmark bar, or by holding Apple while selecting the "Show All Bookmarks" menu item. Similar to how I sometimes want a new page to open in a new window/tab, and sometimes want it to replace the contents of the current tab, this gives me the flexibility to decide.
Interestingly, David Pogue is one of two quoted in Apple page on Vista:
You get the feeling that Microsoft's managers put Mac OS X on an easel and told the programmers, 'Copy that.'
Slashdot Mirror
Not to be pedantic, but lasers most certainly have drop. In fact, the photons in a pulse of laser light fall towards the center of the Earth at exactly the same rate of acceleration as bullets do (namely 32 ft per second per second). It's just that they travel so fast, the transverse velocity they develop (v=gt) and distance off target that they move (d=1/d g t^2) during their short time of flight (t) are negligible.
Most of the depleting rotational energy of the Earth goes into the orbital energy of the moon, which means the moon will be boosted in its orbit and recede from Earth until the Earth is slowed down enough that the same side of the Earth faces the moon as it orbits ("tidally locked"). Which, by the way, is why the man in the moon always faces us (i.e. tidal locking happened long ago on the moon). At that point, a day and Earth an an orbit on the Moon would both last about 47 days. Estimates for when this would occur are around 50 billion years, by which time the sun will have swollen up in its death throes and consumed the Earth. There is some heat generated due to friction from tides and distortions of the Earth's crust, but the rotational-orbital exchange is much more significant.
That is our bias, an observer's bias. For example, "Supernova 1987a" occurred in the Large Magellanic Cloud, a small dwarf galaxy orbiting the Milky Way, which is close to 170,000 light years away. So this star actually blew up just as the first modern Homo Sapiens began wandering around East Africa. Yet we call it "1987a". And for good reason. Many of the supernova we routinely observe in the early universe are reaching us from across such great distances, that they happened well before the Sun and Earth even formed; many perhaps even before the Milky Way galaxy was meaningfully assembled.
I worked a summer as an engineering intern at the largest US manufacturer of breath-alcohol systems. There were dozens of models made to accommodate the wildly varying requirements among states and nations regarding what false positive signals to "rule out". Basically, the systems were very simple infrared spectrometers, made to look for telltale absorption bands of the ethanol molecule in just a few (like 3-4) broad infrared wavelength bands (see e.g. here). The problem is, a large range of simple organic molecules absorb at similar wavelengths. So, for example, to rule out acetone (rotten fruit? nail polish remover?), you'd need to add one or more bands where the two molecules differed in absorption properties. And so on for other molecules with similar optical behavior. I believe the UK had the strongest requirements for ruling out false positives; something like a dozen channels were required (which increased cost, difficulty of calibration, and weight).
Uhhh.. you mean like their "More Search Tools -> Fewer Shopping Sites" option?
It's because implicit in this comparison is the statement "for a fixed field of view and resolution", which implies a focal length, and hence aperture size, which scale with with sensor size: See http://www.clarkvision.com/imagedetail/does.pixel.size.matter/#The_f_ratio_Myth. Large detectors are not intrinsically more sensitive, but for a given field of view and angular resolution, they collect more light than small sensors, going as the square of the its size.
All the scientists I know (myself included) would correctly indicate that the sun will not grow cold, but will, after exhausting its core hydrogen fuel, vastly increase its luminosity, and swell in size past the Earth's orbit, essentially vaporizing it. All this, in roughly 5 billion years.
Modern humans as a species are 0.0002 billion years old. Yes, that's three zeroes to the right of the decimal. Do you really believe that we'll care about a couple thousand years worth of exemplars of humanity after we've evolved 25,000 times further than since we separated from proto-human homonids? Will we even be humans at that point? Are there any other conceivable disasters our species or its descendants could suffer during those billions of years, which colonizing space could not prevent?
Here's a comparison:
The article is wrong on many levels. The key word here is "direct". The 2002 transmission spectra you mention (and others like it) consist of light from the host star, passing through the atmosphere of the planet as it passes in front of it, which imprints spectral signatures of the planetary atmosphere on that stellar spectrum. So in this sense, its not a direct spectrum of the planet's own light, but of the star, modified by the planet in front of it.
The first spectrum of a planet, consisting only of planetary light, came from the Spitzer Space Telescope, which used a differencing technique:
planet + star [out of eclipse] - star [when planet eclipsed] = planet only
The star and planet could not be resolved (separated) by the telescope, but by using the known orbit of this eclipsing planetary system, and timing the observations carefully, a spectrum of the "planet's own light" was obtained.
The novelty of this latest result is that no differencing of this sort was required. Using adaptive optics to correct distortions due to Earth's atmosphere, the light from a star and the light from its associated giant planet where physically resolved, and a spectrum of the planet, all by itself, was obtained. Even with adaptive optics, however, very few systems have star-planet separations on the sky large enough to permit this technique.
Because the bulk of the energy hitting that snow, at optical and ultraviolet wavelengths, is reflected back into space?
From one viewpoint, there is no fundamental difference between them. They scale linearly between two temperature points, assigning values of 0 and 100:
I argue that degrees F offers a more suitable range, and better resolution, than degrees C for temperatures encountered in everyday life. The smallest temperature difference I can detect? Roughly 1 degree F. That's 0.55 degree C. It's also why you often see forecasts in fractional degrees C. A day so cold you have to protect skin? 0 degrees F. A day so hot that wind actually warms you up? 100 degrees F. The advantages of Celsius in the lab are clear. For weather? Not so much.
You are close to correct. Some large number of joules of energy here on Earth arise from material leftover from supernova predating the sun: radioactive materials, which can be harvested directly in fission reactors, or indirectly through tapping the Earth's molten inner they help to heat. The Earth's internal heat also results not from the sun, but from the continued slow tapping of gravitational potential energy from the material from which the sun and its planets formed. This power source is roughly 40 TW, compared to the 100,000 TW of solar power reaching the Earth's surface. Still, several times the current worldwide energy consumption.
Erratum:
"Errata"
Should be:
"Erratum"
My car gets about 30 MPG and after a half hour 30 mile drive is thirsty for a gallon of gas. After a multi-hour 30 mile bike ride I am very hungry and can easily eat two pounds of food (and still lose weight, if it's salad and not eight quarter pounders with cheese and bacon). Anyway, that two pounds of food obviously takes twenty pounds of gasoline to grow and process and ship and cook. Now at 6 pounds of aviation gas per gallon (note I am not a pilot, but that is my fuzzy memory from wanting to be a pilot decades ago) that would make a bit over 3 gallons of gas to grow the food to bicycle 30 miles.
Your argument only works if you assume that otherwise you would not have consumed those 2lbs of food. Obesity-associated illness trends, in the USA at least, would indicate otherwise. By biking, you burn calories you would be eating anyway, improve your health, and save gas too.
When I had comcast and they began this bundling business some 5 years back, it was actually $3 cheaper to get the basic TV service with your internet than no service at all. When I pointed out the inanity to the customer service rep, they kept saying: "It's a package deal, like at McDonalds". To which I replied: "Yes, but since when is the cheeseburger more expensive than the happy meal?"
Yes, forgoing the TV would cost you 3 dollars. After an unproductive 10 minutes on the phone with Comcast, who kept insisting that this was a new Bundling deal that would save me money, I made the following analogy. Imagine if getting just the cheeseburger cost more than getting the whole happy-meal. She wasn't impressed.
I never felt any lack for not having it or thought, "Gee, I wished we messed with the clocks twice a year."
That's because the one thing you absolutely don't need to conserve in the sun-baked 115 degree desert of southern Arizona is..... daylight.
It's not unprecedented. China, which would natively contain 5 times zone, operates under a single time zone, without DST.
Excellent concept. Only Asimov beat you to the punch by 50 years.
All the concern about too many eggs in one basket is certainly valid. However, one major advantage of a centralized login system is being missed here: the ability to change all of one's password easily on a somewhat regular basis. As it stands now, I have so many accounts, many of which use the same password, some of which use variations of that password, etc., that the notion of going through and changing all those passwords is completely daunting. Hence, I never do it.
With openID, every time I got a bit nervous, I could change the one true password, and still have to remember only it. A good openID provider could even give reminders or enforce a password expiration, which would go from extreme nuisance when done on an individual site basis, to real additional security, potentially offsetting the loss of security inherent in the single point of failure for many users.
That's a feature. The bookmarks pane has the semantics of any other page load, which to me is quite intuitive. You can open the bookmark view in a new tab by Apple-clicking the little book icon at the left of your bookmark bar, or by holding Apple while selecting the "Show All Bookmarks" menu item. Similar to how I sometimes want a new page to open in a new window/tab, and sometimes want it to replace the contents of the current tab, this gives me the flexibility to decide.