Weekly Science Updatehttp://www.cfa.harvard.edu/news/Weekly Science Updateen-us Effective Teachershttp://www.cfa.harvard.edu/news/2013/su201318.htmlMay 03, 2013: Everybody wants teachers to be knowledgeable, but there is little agreement on what kinds of knowledge are the most important. Magnetic Imaging of Living Cellshttp://www.cfa.harvard.edu/news/2013/su201317.htmlApril 26, 2013: Magnetic field measurement techniques have long enabled scientists to probe the internal structure of biological and material samples. Supernovae and the Origin of Cosmic Rayshttp://www.cfa.harvard.edu/news/2013/su201316.htmlApril 19, 2013: In the spring of the year 1006, one thousand and seven years ago this April, observers in China, Egypt, Iraq, Japan, Switzerland (and perhaps North America) reported seeing what might be the brightest stellar event in recorded history. A Challenge to Cosmologyhttp://www.cfa.harvard.edu/news/2013/su201315.htmlApril 12, 2013: The universe was created about fourteen billion years ago in a blaze of light known as the big bang. Galaxy Collisionshttp://www.cfa.harvard.edu/news/2013/su201313.htmlApril 05, 2013: Collisions between galaxies are common. Indeed, most galaxies have probably been involved in one or more encounters during their lifetimes. The Distant Cosmos as Seen in the Infraredhttp://www.cfa.harvard.edu/news/2013/su201314.htmlMarch 29, 2013: At some stage after its birth in the big bang, the universe began to make galaxies. No one knows exactly when, or how, this occurred. Galaxies the Way They Werehttp://www.cfa.harvard.edu/news/2013/su201312.htmlMarch 22, 2013: Galaxies today come very roughly in two types: reddish, elliptically shaped collections of older stars, and bluer, spiral shaped objects dominated by young stars. Heating the Solar Windhttp://www.cfa.harvard.edu/news/2013/su201311.htmlMarch 15, 2013: The Sun glows with a surface temperature of about 5500 degrees Celsius. Meanwhile its hot outer layer (the corona) has a temperature of over a million degrees, and ejects a wind of charged particles at a rate equivalent to about one-millionth of the moon's mass each year. A New Telescope Probes a Young Protostarhttp://www.cfa.harvard.edu/news/2013/su201310.htmlMarch 08, 2013: IRAS 16293-2922B is a very young star - a protostar - perhaps only about ten thousand years old. Slightly smaller in mass than our Sun, it is still deeply embedded in its surrounding natal material, and apparently is even accreting some of that material onto a circumstellar disk that rings the protostar. An Updated List of Potential Exoplanetshttp://www.cfa.harvard.edu/news/2013/su201309.htmlMarch 01, 2013: There are currently 861 exoplanets (planets around other stars) according to the official exoplanet encyclopedia website. Diagnosing the X-Ray Variability of a Galaxy's Nucleushttp://www.cfa.harvard.edu/news/2013/su201308.htmlFebruary 22, 2013: An active galaxy is one whose nucleus contains a massive black hole that is vigorously accreting material. In the process, the nucleus typically ejects jets of particles and radiates brightly at many wavelengths, in particular at X-ray wavelengths. Hydrogen Masers in Spacehttp://www.cfa.harvard.edu/news/2013/su201307.htmlFebruary 15, 2013: Astronomers in the 1960s were amazed to discover that molecular clouds in interstellar space sometimes produced natural masers (the radio wavelength analogs of lasers) that shine with bright, narrow beams of radiation. The Spins of Black Holes in Galactic Nucleihttp://www.cfa.harvard.edu/news/2013/su201306.htmlFebruary 08, 2013: Supermasssive black holes, having masses of millions or even billions of suns, are found at the nuclei of galaxies. In dramatic cases like quasars, these black holes are responsible for spectacular phenomena like the ejection of narrow jets of particles at nearly the speed of light. Solving a Mystery of the Sun's Coronahttp://www.cfa.harvard.edu/news/2013/su201304.htmlFebruary 01, 2013: The corona of the sun is the hot (over a million kelvin), gaseous outer region of its atmosphere. The corona is threaded by intense magnetic fields that extend upwards from the surface in braids that are twisted and sheared by the convective stirrings of the underlying dense atmosphere. Giant, Magnetized Outflows from our Galactic Centerhttp://www.cfa.harvard.edu/news/2013/su201303.htmlJanuary 25, 2013: Two years ago, CfA astronomers reported the discovery of giant, twin lobes of gamma-ray emission protruding about 50,000 light-years above and below the plane of our Milky Way galaxy, and centered on the supermassive black hole at our galaxy's core.