- 100 Years Ago in Antarctica to the day
On October 28, 2010, astronomers working on the (associated with the ; see Andrew Howard's ) announced that "-sized" planets (with 0.5 to two Earth-masses) are probably common around "Sun-like" (i.e., ) stars. The astronomers used the for five years to search around a random sample of 166 Sun-like stars of spectral types G, K, and M from 235 of a much larger population of such stars located within 25 parsecs (81.5 light-years) of suitable brightness, luminosity, and low chromospheric activity for planets orbiting their host star within only one fourth of an astronomical unit (0.25 AU), which is less than that of 's average orbital distance of 0.4 AU in the and the equivalent of an orbital period (or "year") of only 50 days or less. Using to detect a "wobble" of about one meter per second, they looked for planets ranging from 1,000 to as little as three times the mass of Earth that they are now able to detect with that method, and then they extrapolated downward for smaller planets. Finding 33 such close-orbiting planets around 22 stars (with 12 planets around 10 more stars still to be confirmed) from the random sample of 166 Sun-like stars, the astronomers determined that many more small planets were found than large ones, which suggests that small planets are more prevalent in Sol's region of the , and possibly elsewhere as well.
This process is called globalisation.
Productivity and employment are key policy issues. Gauging which kind of firms thrive or struggle within countries is crucial to understand differences in aggregate productivity and employment across countries. The Science, Technology and Innovation Directorate leads the DYNEMP and MULTIPROD projects to provide cross-country comparable evidence for policy making in these areas.
Australia has a choice. Put downward pressure on wages and salaries to make Australia more competitive or face a greater disaster – become uncompetitive and see unemployment begin to rise to potentially dangerous levels. The Workplace Relations Act 1996 was a landmark reform of the Howard government but somewhat unpopular. It was perhaps a lesser of two evils.
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On January 11, 2012, scientists working on NASA's team announced the discovery of the three smallest planets yet detected, which are in tight orbits around a dim star located around 130 light-years away in . The planets have hot, uninhabitable inner orbits lasting less than two days around a red dwarf (spectral type M) star designated KOI-961 and have only 0.78, 0.73 and 0.57 times Earth's diameter (where the smallest may be as small as Mars). The planets' diameters were estimated by modelling the observed dips in starlight with the well-known characteristics of nearby , which appears to be a near-twin of KOI-961 (NASA and ; Vanderbilt University ; Kepler ; JPL ; and ).
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On February 2, 2011, the revealed the detection of 54 potential which orbit their within or near its apparent habitable zone -- where liquid water can exist on the surface of an Earth-type planet. Five of these planets are near Earth in size, but they orbit stars that are smaller, dimmer, and more orange-red than our own Sun, . While the other 49 are larger, some astronomers wonder if any of them have moons that could be massive enough to support Earth-type life (NASA/Kepler ).
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On January 26, 2012, scientists working on NASA's team announced the discovery of 11 new planetary systems hosting 26 confirmed planets, as well as additional planetary candidates. These discoveries nearly double the number of confirmed planets discovered using the Kepler space telescope and triple the number of stars known to have more than one planet that "transits" in front of its host star. Fifteen of the newly confirmed planets are estimated to be only between and in size, and the smallest may have a diameter only 50 percent larger than Earth's (). The smallest planet orbits , a star older and more massive than our Sun, , which also had the most detected planet candidates at five (ranging in size from 1.5 to 5 times that of Earth) in uninhabitable, hot inner orbits closer to their star than even around our Sun (NASA Kepler ; and JPL ).
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The five "Earth-sized" have estimated planetary diameters within range of being Earth-sized (0.5 to 1.25 times Earth's diameter) given error margins ranging from 25 to 35 percent due to the uncertainty in the size of their and of the "depth" of the observed transits (decrease in stellar luminosity) across the surface of the star. For each planetary candidate, the equilibrium surface temperatures are derived from "grey-body spheres without atmospheres ... [and] calculations assume a Bond albedo of 0.3, emissivity of 0.9, and a uniform surface temperature ... [with uncertainties of] approximately 22% ... because of uncertainties in the stellar size, mass, and temperature as well as the planetary albedo." Actual planetary surface temperature would likely be higher due to warming by any atmosphere gases that might be present (, pp. 21-23, Table 6).