By Patricia Daukantas

During his plenary speech at last week’s Frontiers in Optics (FiO) meeting, John C. Mather, one of the 2006 Nobel Prize winners in physics, described the optical systems that will go into the James Webb Space Telescope (JWST), which is scheduled for launch in 2013. Mather, a senior astrophysicist at NASA’s Goddard Space Flight Center (USA), spent 15 years taking the Cosmic Background Explorer (COBE) satellite, which measured the faint afterglow from the Big Bang that created the universe.

Mather spent 15 years taking COBE from the proposal stage to its 1989 launch. He was the principal investigator for the COBE instrument called the Far Infrared Absolute Spectrophotometer (FIRAS), which measured the black-body spectrum of the cosmic background radiation from the Big Bang to unprecedented accuracy. (When he first showed his experiment-matches-theory result to an astronomers’ meeting in January 1990, his colleagues gave him a standing ovation.)

Mather’s current project, JWST, involves almost every section of NASA. The planned 6.5-m space telescope looks a little like a solar energy concentrator in the desert, he said, because it needs to have a multilayered sunshade in order to operate at a temperature of 40 K. JWST will be launched on an unmanned Ariane booster rocket and will fly to the L2 Lagrangian point, a stable position about 1 million miles on the opposite side of Earth from the Sun. After showing an animation of the way the telescope is supposed to unfold by itself once it reaches L2, Mather quipped, “If you’re a mechanical engineer, this is either terrifying or thrilling.”

JWST will use a three-mirror anastigmat optical design for a wide field of view. (In addition to the primary and secondary mirrors, it will have a “fine steering mirror” at the Cassegrain focus.) The scientists selected a beryllium mirror because of its superior cryogenic properties—it undergoes much less thermal distortion than the ultra-low-expansion glass used in many ground-based telescopes.

Among JWST’s many cameras will be NIRSpec, a near-infrared imaging spectrograph that can photograph 100 galaxies at once. “If it takes two weeks to get an exposure, we don’t want to be limited to just one galaxy,” Mather said.

Since data from the Hubble Space Telescope showed that galaxies were formed longer ago than scientists had thought, JWST is likely to study the origins of galaxies and the earliest populations of stars. JWST could also study Earth-like transiting planets, or planets that pass between their parent star and the observer. Astrophysicists over the years have proposed a number of schemes for orbiting planet-hunting interferometers, with instruments mounted on widely spaced satellites, but tight budgets at the space agency may mean that not all of those projects will fly.

2008-10 October, Astronomy astronomy, astrophysics, nobel prize, fio, telescopes

By Patricia Daukantas

Days 3 and 4 (Tuesday and Wednesday) of Frontiers in Optics, OSA’s annual meeting, have been the chilliest and rainiest so far. Inside the Rochester Convention Center, however, the atmosphere has been sunny, as OSA members have been making and renewing friendships and learning from each other in a spirit of collegiality.

Tuesday’s highlight was a day-long symposium honoring the founding of NASA 50 years ago this month. A couple of the invited speakers were unable to attend because they’re working hard on the latest, non-optical troubles facing the Hubble Space Telescope (see my previous blog post here). The other speakers described the original 1993 remedy for Hubble’s defective primary mirror – a masterpiece of technological detective work if there every was one – as well as the upcoming James Webb Space Telescope (JWST) and planet-seeking coronagraphs that may or may not ever leave the NASA drawing boards. Several folks from the JWST team had to leave after the symposium for a telescope team meeting in San Francisco; it was awesome that they were able to give us their time on the way there.

At Tuesday’s OSA Member Reception, President Rod Alferness reminded the gathering that this is the 50^th consecutive Annual Meeting at which the University of Rochester’s own Emil Wolf is presenting a paper. Besides his invited talk on Wednesday morning, Wolf is a co-author on six other papers. Truly indefatigable. (Incidentally, in future years the OSA Foundation will hold a Student Paper Competition dedicated to Emil Wolf.)

The reception ended with dozens of young members piling on the dais and posing for group photos in front of the “Welcome to OSA Student Chapters” banner. Undoubtedly, these smiling grad students will in 20 years become the entrepreneurs and professors who will mentor a whole other generation of optical scientists.

Wednesday’s highlights include a symposium on polarized light, the Minorities and Women in OSA luncheon, and postdeadline papers in the evening.

2008-10 October, Astronomy astronomy, astrophysics, fio, space telescopes, telescopes, students

Optics, Video Games and Shakespeare

By Patricia Daukantas

Greetings from Rochester! I am in this upstate New York community, where OSA was born, to attend Frontiers in Optics (FiO), our 92^nd annual meeting. This week I’ll be blogging from the conference.

Already I’ve been learning some cool things. Did you know, for example, that playing action video games may help your vision? Or that Shakespeare foreshadowed quantum optics?

During Sunday’s session titled “What’s Hot in Optics,” a useful road map to the FiO technical program, Daphne Bavelier of the University of Rochester’s Center for Visual Science reported that test subjects showed significant improvements in the spatial and temporal resolution of their visual processes after 10 hours of playing fast-paced action video games—the ones that require gamers to move quickly and “shoot” targets after making split-second decisions. Perhaps someday auto insurance companies will offer discounts to older drivers who expand their useful field of view by playing these action games.

OSA Past President (2004) Sir Peter Knight, this year’s recipient of the Frederic Ives Medal/Jarus Quinn Endowment, quoted a famous soliloquy from Macbeth in introducing his field of quantum optics and speculating on the non-classical nature of reality. Okay, so Shakespeare didn’t really use the word “quantum,” but you can ponder his words yourself:

Is this a dagger which I see before me

The handle toward my hand? Come, let me clutch thee.

I have thee not, and yet I see the still.

Art thou not, fatal vision, sensible

To feeling as to sight? Or art thou but

A dagger of the mind, a false creation,

Proceeding from the heat-oppressed brain?

I see thee yet, in form as palpable

As this which now I draw.

Watch for OPN’s first-ever podcast after the conference. The podcast will feature exclusive content, including interviews with several distinguished invited speakers.

2008-10 October, Optics and pop culture fio, osa, video, vision

By Patricia Daukantas

Optical technologies such as laser scanning confocal microscopy (LSCM) and multiphoton excited (MPE) fluorescence microscopy have given researchers wonderful new ways to image live cells and biological tissues. Today the Nobel Prize in Chemistry went to three scientists who found something for these state-of-the-art microscopes to see.

Back in 1962, Japanese cell biologist Osamu Shimomura of the Marine Biological Laboratory and Boston University Medical School (both in Massachusetts, U.S.A.) first isolated the substance known as green fluorescent protein (GFP) from the Aequorea victoria jellyfish and discovered that it produced a fluorescent glow under ultraviolet light. American biologist Martin Chalfie of Columbia University (New York, U.S.A.) showed that GFP could act as a luminescent “tag” that traces biological phenomena. American biochemist Roger Y. Tsien of the University of California at San Diego (U.S.A.) studied how the fluorescence mechanism of GFP works and extended the phenomenon to other colors and other proteins.

In the June 2003 issue of OPN, Paul Campagnola and William A. Mohler explained how GFP works: “[T]he gene that encodes for it can be linked to the gene of virtually any cellular protein of interest. The resulting fusion is then placed in cells or a whole organism and the desired protein is expressed with the GFP label.”

Scientific American has a nice article explaining the significance of GFP, and in a statement, the president of the American Chemical Society, Bruce Bursten, said, “Green fluorescent proteins allow scientists quite literally to see the growth of cancer and study Alzheimer’s disease and other conditions that affect millions of people.”

At OSA conferences, I’ve heard many researchers describe how they used fluorescent proteins as part of their experiments to improve biomedical imaging. One example of this work is a “Scattering” published back in February 2008, describing a retinal flow cytometer. A quick search of Optics InfoBase reveals numerous articles on work involving GFP in such OSA journals as Optics Express and JOSA A as well as OSA conference proceedings.

Quantum dots are starting to supplant fluorescent proteins in biomedical imaging because of their longer lifetimes and increased flexibility. Nevertheless, GFP and its glowing-protein cousins will remain an important component of the biomedical imaging toolbox for years to come.

2008-10 October, Biomedical optics nobel, nobel laureates, nobel prize, biomedical optics