John C. Mather
NASA
Leigh Page Prize Lecture Series
Monday, September
28, 2009
4:30 pm in SPL 57, Tea at 3:45 in SPL 3rd Floor Lounge
How did the Universe make people? A brief history of the Universe, from the beginning to the end
Abstract: Astronomers are beginning to know the easy part: How did the Big Bang make stars and galaxies and the chemical elements? How did solar systems form and evolve? How did the Earth and the Moon form, and how did water and carbon come to the Earth? Geologists are piecing together the history of the Earth, and biologists are coming to know the history and process of life from the earliest times. But is our planet the only life-supporting place in the universe, or are there many? Astronomers are working on that too. I will tell the story of the discovery of the Big Bang by Edwin Hubble, and how the primordial heat radiation tells the details of that universal explosion. I will tell how the James Webb Space Telescope will extend the discoveries of the Hubble Space Telescope to ever greater distances, will look inside dust clouds to see stars being born today, will measure planets around other stars, and examine the dwarf planets in the outer Solar System. I will show concepts for great new space telescopes to follow the JWST and how they could use future moon rockets to hunt for signs of life on planets around other stars.
Tuesday, September
29, 2009
4:30 pm in SPL 57, Tea at 3:45 in SPL 3rd Floor Lounge
Progress on the James Webb Space Telescope - Successor to the Hubble Space Telescope
Abstract: I will describe the scientific program anticipated for the James Webb Space Telescope and the progress in its construction. When the JWST was conceived in 1995 it was expected to make its greatest contributions in the study of the first objects to form after the Big Bang, in the evolution of galaxies, and in the formation and evolution of stars and planetary systems. Since then, the age-distance-redshift relation has become clear with the precise measurement of the Hubble constant, the discovery of the accelerating universe, and the remarkable agreement of CMBR calculations with direct measurements of the large-scale structure. So what is left and what has changed? Galaxy formation and growth is still mysterious, star formation is still hidden, the dark matter and dark energy are still unobservable, and the tools at hand may or may not help enough. But the JWST, as a general-purpose observatory, will be available for imaginative use, and is just what Simon White’s polemic seems to request. As an example, the JWST should be quite capable of observing transiting exoplanets with remarkable precision, even though there was no requirement to do so, and its coronagraphs will be very good even without a monolithic primary mirror.
The JWST mission has now been officially approved by NASA and is in the Federal budget. It is planned for launch in 2014. Flight instruments will begin to arrive at Goddard in mid-2010, and the first flight mirror segments have already passed their first cryogenic tests. The flight detectors have been selected and have remarkable performance; for example, the near IR detectors have dark currents of the order of 10 electrons per pixel per hour.
Wednesday, September
30, 2009
4:30 pm in SPL 57, Tea at 3:45 in SPL 3rd Floor Lounge
Basic physics questions addressed by astrophysics
Abstract: Dark matter, dark energy, the Big Bang, testing relativity – all are physics questions accessible to astrophysicists – but all require new equipment. As Harwit’s “Cosmic Discovery” pointed out, almost all great surprises in astronomy came from new equipment or new uses of equipment designed for other purposes, and many of those had military applications. I will outline prospects for new equipment and discuss how that equipment can be developed and built. Bigger and lighter mirrors, wavefront sensing and control, new detector technology, cryogenics – each has its own social network, its own special possibilities, and its own funding sources outside science. I will discuss some examples drawn from real-life experience with the James Webb Space Telescope, a telescope that was said to have a “giggle factor” when it was proposed in 1995. Now each of the 10 major technologies has been brought to maturity, flight hardware is being built, and launch is planned for 2014. As an instrument builder all my life, I will speculate a little on what may be within our reach over the next few decades.
[RETURN]