Spitzer lifts the cosmic veil

Where did we come from? Are we alone? These questions have driven scientific inquiry for centuries, and frame the agenda for modern astrophysical studies. Since August 2003, astronomers have had a powerful new tool for delving into these mysteries: the Spitzer Space Telescope, developed and launched for NASA under the leadership of the Jet Propulsion Laboratory and now operated by Caltech’s Spitzer Science Center. On Wednesday, March 9, at 8 p.m., Michael Werner, the Spitzer project scientist at JPL, will discuss the Spitzer in his talk, “Lifting the Cosmic Veil: The Infrared Universe Revealed by the Spitzer Space Telescope,” part of the Ernest C. Watson Lecture Series.

The Spitzer explores the heavens at infrared wavelengths, the heat radiation emitted by celestial objects. That allows astronomers to study the coldest, most distant, most hidden objects in the universe. Cool dim objects like small stars, brown dwarfs, and planets emit electromagnetic radiation most strongly in the infrared, the wavelengths of which are longer than those of visible light, and which can pass through the interstellar dust clouds that often shroud new stars. But Earth’s atmosphere blocks infrared light. As a result, prospective infrared astronomers have had to turn to space.

Launched in August 2003, the Spitzer Space Telescope is the fourth of the NASA Great Observatories, a program that also includes the Hubble Space Telescope, Chandra X-ray Observatory, and Compton Gamma Ray Observatory. The Spitzer design incorporates major innovations in cryogenics, optics, and infrared detector arrays into an extremely efficient and cost-effective telescope that achieves a thousandfold increase in capability over previous infrared space observatories.

Werner has been working on the Spitzer since 1977 and has been Project Scientist since 1984. He is responsible for seeing that the mission’s scientific objectives are clearly defined and that the telescope’s scientific performance will achieve those objectives. In his talk, Werner will describe the technical and scientific principles that power the Spitzer, and display and explain the Spitzer’s images and spectra (graphical representations of a celestial object’s unique blend of light), and the revolutionary scientific results they have produced.

Caltech has offered the Watson Lecture Series since 1922, when it was conceived by the late Caltech physicist Earnest Watson as a way to explain science to the local community. Seating for this free public event in Beckman Auditorium on the Caltech campus is on a first-come, first-served basis, beginning at 7:30 p.m.

For more information, contact Public Events at 1 (888) 2CALTECH, (626) 395-4652, or events@caltech.edu, or visit www.events.caltech.edu. Individuals with a disability can call (626) 395-4688 (voice) or (626) 395-3700 (TDD). All lectures will be available online at Caltech’s Streaming Theater, http://today.caltech.edu/theater.
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