The X-Ray Universe: How Superman Sees the Stars (NEW RELEASE!)
David Helfand has been a Professor of Astronomy at Columbia University for 47 years, where he served as chair of the Department for two decades. He is also the former President of the American Astronomical Society and of Quest University Canada, and currently serves as Chair of the American Institute of Physics. Professor Helfand has received the Columbia Presidential Teaching Award and the Great Teacher Award from the Society of Columbia Graduates. He is the author of A Survival Guide to the Misinformation Age and, recently The Universal Timekeepers: Reconstructing History Atom by Atom.
Overview
Almost all our knowledge of the Universe comes to us in the form of light waves. We imagine our personal light detectors — our eyes — are marvelous instruments, providing us with a highly colorful view of the world. But in a cosmic sense, they are really quite pathetic: human eyes are sensitive to just a single octave of colors — a factor of two in wavelength — while the Universe send us over 60 octaves of waves to which we are completely blind.
Over the past 75 years, astronomers have been building telescopes and cameras that open windows on these other octaves of light. In particular, beginning in the 1950s, we sent rockets above the atmosphere to observe the cosmos in the light Superman sees — X-rays. In 1999, we launched by far the most sensitive, highest resolution observatory for X-ray light, Chandra. Over the past twenty-five years, Chandra has been sending back exquisite images of the hottest and most energetic denizens of the Universe, from the sites of recent star formation to the remnants of exploded stars, and from the hot gas in galaxies and clusters of galaxies to the most distant quasars. This session provides a tour of the Chandra Universe to reveal how Superman sees the stars.