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Happy New Year!

New Year 2009 was a leap second longer than normal. Who decides that we are going to change our clocks?

The International Earth Rotation and Reference Systems Service (IERS) that is who.

Leap seconds, added once every 500 days or so, keep high-precision atomic clocks from running ahead of solar time, which is gradually falling behind as tidal friction slows Earth’s rotation. Michael Schirber.  (2005). U.K. Stargazers: Save the Leap Second. Science, 309(5744), 2147.

Deciding whether and when a leap second is needed falls to an international organisation called the International Earth Rotation and Reference Systems Service (IERS). It collects and averages measurements of the Earth’s rotation from around the world. Each January and July it issues a notice announcing whether a leap second is required in the next six months. James Randerson,  Science correspondent. (2008, December 31). Front: 5, 4, 3, 2, 1 … er 1. New Year to take extra second to reach big bang: Atomic clocks come into line with astronomical day: Erratic rotation of Earth creates need for change. The Guardian,3.

The periodic insertion of a leap second step into the scale of Coordinated Universal Time (UTC) necessitates frequent changes in complex timekeeping systems and is currently the subject of discussion in working groups of various international scientific organizations. UTC is an atomic time scale that agrees in rate with International Atomic Time (TAI), but differs by an integral number of seconds, and is the basis of civil time. In contrast, Universal Time (UT1) is an astronomical time scale defined by the Earth’s rotation and is used in celestial navigation. R A Nelson, D D McCarthy, S Malys, J Levine, B Guinot, H F Fliegel, R L Beard and T R Bartholomew Satellite Eng. Res. Corp., USNO, NIMA, NIST, OP, Aerospace Corp., NRL, Litton TASC Inc.

The International Earth Rotation Service (IERS) was established in 1987 by the International Astronomical Union and the International Union of Geodesy and Geophysics and it began operation on 1 January 1988. It replaced the International Polar Motion Service (IPMS) and the earth-rotation section of the Bureau International de l’Heure (BIH); the activities of BIH on time are continued at Bureau International des Poids et Mesures (BIPM). Since 1 January 2001 the IERS has got a new structure. In 2003 it was renamed to International Earth Rotation and Reference Systems Service.

The definition of UTC was implemented in 1972, principally to accommodate celestial navigation and follows recommendation 460 of the International Radio Consultative Committee (CCIR) in 1970. Since 1972 the use of electronic means to navigate has overtaken celestial navigation. Dennis McCarthy,  F Arias,  W Dick,  D Gambis,  M Hosokawa,  W Klepczynski,  S Leschiutta,  J Laverty,  Z Malkin,  D Matsakis,  R Nelson,  J Vondrak,  P Wallace,  N Capitaine,  T Fukushima. (2005). Division I Working Group on “Definition of Coordinated Universal Time”. International Astronomical Union. Proceedings of the International Astronomical Union, 1(T26A), 63-66.

The leap second has been used sporadically at the Royal Observatory at Greenwich since 1972, an adjustment that has kept Greenwich Mean Time the agreed time standard.

Some scientists now say GMT should be replaced by International Atomic Time - computed outside Paris - because new technologies have allowed atomic time to tick away with down-to-the-nanosecond accuracy.

But opponents say atomic time’s very precision poses a problem. A strict measurement, they say, would change our very notion of time forever, as atomic clocks would one day outpace the familiar cycle of sunrise and sunset.

Atomic time advocates argue that leap seconds are onerous because they’re unpredictable. Since the exact speed of the Earth’s rotation can’t be plotted out in advance, they’re added as needed. Sometimes they’re added Dec. 31; other times at the end of June.

Those fixes can trip up time-sensitive software, particularly in Asia, where the extra second is added in the middle of the day.

Critics say everything from satellite navigation to cellular communication is vulnerable to problems stemming from programs ignoring the extra second or adding it at different times. Raphael G. Satter,  Jamey Keaten Associated Press. (2008, December 31). Wait a sec, 2009; Earth’s running late. Journal - Gazette,A.10.

So what is the time?

Tags: Atomic, Clocks, Earth, Measurement, Rotation, Time, Universal.

It is certainly funny to look back at predictions after an event has occurred and think how ridiculous our ideas were and how much gets blown out of proportion.

Does this story sound similar to the boy who cried wolf?

Is there a good reason to feel in a constant state of panic and anxiety?

Over the past century or so, forecasters have made sweeping declarations about the future. In many cases, the expert opinion held with regard to any given situation was that “it couldn’t be done.” As often as not, expert opinion was wrong. Dennis Behreandt.  (2006, June). They Said It Couldn’t Be Done… The New American, 22(13), 36-38.

Naive egocentric catastrophism is not based on sound science. Instead, it borders on pseudoscience, and discourages serious and sober debate on the scientific issues in potential catastrophes arising from global warming, depletion of resources, terrorism, and all the rest. Mordechai (Moti) Ben-Ari.  (2006, January). Whose Final Hour? Skeptic, 12(3), 40-49,80.

Interpretation of bold statements needs to be just that. When it comes to predicting the future, disclosure is needed to ensure that the statement is taken in context. For example the following is a list of predictions that were if not anything else, simply grand ideas:

One Toe?

Richard Lucas of the Royal College of Surgeons in England made the unlikely prediction that some day human beings in the future would become one-toed. “The small toes are being used less and less as time goes on,” he opined, “while the great toe is developing in an astonishing manner.” Cynthia Crossen.  (2007, January 8). Perils of Prediction: Seeing Rubber Cities And an End to Cars. Wall Street Journal (Eastern Edition),  p. B.1.

Rubber Streets

In 1914, Sir Henry Blake, a British government official, foresaw the noiseless city, where rubber would replace brick, stone and asphalt as street paving. Cynthia Crossen.  (2007, January 8). Perils of Prediction: Seeing Rubber Cities And an End to Cars. Wall Street Journal (Eastern Edition),  p. B.1.

Need for Speed

In 1911 Barney Oldfield, at the time one of America’s most famous race car drivers, argued that cars were plenty fast enough and that further development for speed was unnecessary. “The science of speed has reached a point where any manufacturer can produce a car which will satisfy any sane buyer,” Oldfield wrote. “There is no demand and little need for further development along speed lines.” Dennis Behreandt.  (2006, June). They Said It Couldn’t Be Done… The New American, 22(13), 36-38.

Does anyone remember the predictions around Y2K and perhaps even the paperless office?

Paperless Office

The paperless office used to be one of those high concepts everybody talked about, half in geeky boastfulness, half in jest, always in reference to a somewhat distant tomorrow. A remote and ambitious idea, it was right up there with robot butlers (think of Woody Allen’s “Sleeper,”) Big Brother biometrics, and a Star Wars missile defense system.

Dog-eared files and Post It notes remain in evidence at many a bank, as they simply haven’t bought into paperless schemes, or the technology, in some cases, has failed to deliver. Lauren Bielski.  (2002). So, what ever happened to the paperless office? American Bankers Association. ABA Banking Journal, 94(6), 57-58+.

When bold predictions about the future are made, we should take them into context and perhaps adopt a ‘wait and see’ attitude. Too often we just believe the hype.

Tags: Anxiety, Forecast, Future, Hype, Prediction.

I once had a friend that gave me a flyer for her birthday party. The event advertised that it had intelligent lighting however she had incorrectly spelt intelligent. Oh well, she wasn’t too bright. The following is a guide to the latest technology and bright ideas in lighting:

New and emerging lighting technologies such as LEDs (light-emitting diodes) can improve lighting quality while reducing maintenance and energy costs.

There are numerous technologies used in lighting, including tungsten incandescent, quartz halogen, fluorescent, and LED. Low-pressure sodium is more common in such outdoor applications as street lighting. These various technologies have distinctive advantages and disadvantages. The most familiar “light bulbs” have been around tor more than 100 years, and they are inexpensive. But a major disadvantage is that they are inefficient and waste a lot of energy in the form of heat. In addition, incandescent bulbs have a short lifetime. Incidentally, the regular screw-in base is called the “Edison base,” which can be useful to know for online searching. Fluorescent lighting is a great deal more efficient than incandescent lighting, but the tubes are fragile, require ballasts that sometimes hum, and contain mercury. Newer compact fluorescents eliminate many of the disadvantages of the large fluorescent tubes. Halogens are more efficient than incandescents but share many of their disadvantages. (Royal Van Horn.  (2006). LEDs and Home Lighting Technology. Phi Delta Kappan, 88(2), 103,169.)

The first LEDs in 1962 consisted of a layer a few atoms thick of the compound semiconductor material, gallium arsenide. Robust and taking very little power, they were ideal as indicators. They could give only red light, but their high efficiency compared with all other electric lights led people to ask whether a bright white LED could be developed for general illumination. The problem was solved by Shuji Nakamura, born in 1954 on Shikoku, the smallest of Japan’s four main islands. Nakamura had studied electrical engineering at a local university, where he became fascinated with solid-state physics and obtained a master’s degree.

Nakamura saw that the key to solving the problem was the development of an efficient bright blue LED. If he could achieve that, he could also make a green LED, and by combining red, green, and blue LEDs produce white. Although blue LEDs based on silicon carbide were being developed by other researchers, their efficiency was very low. Nakamura’s studies led him to conclude that the blue LED should be based on gallium nitride, but forming a thin, single-crystal layer of gallium nitride was extremely difficult. (Brian Bowers.  (2008). Brilliant! Shuji Nakamura and the Revolution in Lighting Technology. Review of Technology and Culture, 49(2), 479-481.)

The newest kid on the block, LEDs are 10-20 times more efficient than incandescents, so they use substantially less electricity. LEDs are also rugged and have a lifetime of more than 100,000 hours. Because I get tired of changing light bulbs, this is a very attractive feature. LEDs are small, so they must be combined into arrays or clusters. And because LEDs are low-voltage devices, using them in home lighting requires a power supply. In an LED light bulb, this power supply is built into the base of the bulb.

LEDs deliver a different correlated color temperature (CCT) compared to the old incandescent lamps; 6500K for the new LEDs compared to 2600K for the incandescent lamps. The scotopically enhanced color from the new LEDs provides an improved perception of overall brightness.

The fiber optic lighting system uses a remote source light. The light is channeled into a fiber optic distribution system and emitted into the space by an illuminator. The illuminator uses optics designed to match the application to illuminate the product. The new fiber optic lighting system requires less overall power and energy. (Steven Parker,  Joseph Konrade,  E Carroll Shepherd III. (2009). New Lighting Technologies Demonstrated at Defense Commissaries. Energy Engineering, 106(2), 7-18.)

Energy-efficient lighting technologies have been available for five to 10 years but have yet to make significant inroads into the market. The biggest deterrent seems to be the initial cost of retrofitting. “It takes more than just replacing standard bulbs with more energy efficient ones,” explains Alden Hathaway, Sylvania’s manager of pricing and applications. “Generally, a company needs to research various options for lighting a particular area, and it may be necessary to change the entire fixture in order to put in place the best lighting solution.”

“Lighting is usually handled by facilities managers and is not considered a management item,” another industry spokesperson says. “Typically, building managers are not positioned to ask for an increase in their budgets. So, many continue to purchase conventional lighting rather then retrofit for systems that offer lower lifecycle costs through electricity savings.”

Such thinking may be increasingly penny-wise and pound-foolish. According to industry experts, organizations may see a payback in the shape of lower electric bills in as little as one year. (Peak, Martha H.  (1993). A brighter, lighter business idea. Management Review, 82(8), 8.)

Tags: Bright, Energy, Fibre Optic, Fluorescent, Incandescent, LED, Light-Emitting Diodes, Lighting, Nakamura.

It was sad to learn that Pluto was no longer classed as planet. I liked the idea of a distant world. As a child in school, we were asked to draw the planets, however nobody knew the colour of Pluto, so I used all my colours to colour in the distant planet. Later, when I was told that Pluto changes colour I was pleased that my interpretation was the most accurate. I think the unknown can create a special bond.

Astronomers have debated Pluto’s planetary status for more than a decade, but the recent discovery of two new moons orbiting the distant ice world makes its identity crisis more acute. When the first moon, Charon, was discovered in 1978, only planets were known to have moons, and possession of a moon seemed to raise Pluto’s declining status. Ray Villard (2006, June). Are Pluto and Earth two of a kind? Astronomy, 34(6), 48-51.

According to one proposed definition, a planet is any large object whose own shape is rounded by gravity. By that rule, the solar system is now home to at least 50 planets, and could have far more. But other definitions would draw the line far differently. According to one proposal, a “planet” must be more massive than the total mass of all the other bodies in a similar orbit. That would disqualify Pluto, leaving an eight-planet solar system. Beth Daley, GLOBE STAFF (2004, March 30). WHAT IS A PLANET? GROUP SEARCHES FOR A DEFINITION SEDNA DISCOVERY PROMPTS A DEBATE :[THIRD Edition]. Boston Globe,p. C.1.

In 2005, [Michael Brown], the Richard and Barbara Rosenberg professor of planetary astronomy at California Institute of Technology, discovered Eris, the largest object found in the solar system in the last 150 years. Eris, which is larger than Pluto, caused astronomers to rethink the definition of what a planet is, ultimately leading to Pluto being redesignated as a dwarf planet. Astronomer to speak about Pluto demotion. (2008, December 1). News Journal,C.4

The IAU demoted Pluto in 2006 because it is unlike every planet from Mercury to Neptune in one major respect yes, it’s round, and yes, it orbits the sun. But it lacks pull; its gravity isn’t strong enough to clear the neighborhood of small objects the way that Mercury and the other planets do. So little Pluto was designated a dwarf planet So was Ceres, a similar-sized round object that circles the sun in the asteroid belt between Mars and Jupiter.

The IAU changed its mind again this year because Pluto’s far-out location in our solar system makes it less like Ceres and more like Eris, another small sphere beyond Neptune that circles the sun. Ceres remains a dwarf planet, but Pluto and Eris are now plutoids. Pluto Is Now a Plutoid. (2008). Current Science, 94(3), 12-13.

No matter what they say you are, Pluto we still love you.

Tags: Astronomy, Discover, Dwarf, Planet, Pluto, Plutoid.