Question of the month: How long is a radio wave, and how do you measure it?

Question of the Month Answered by: Sterl Phinney, Associate Professor of Theoretical Astrophysics

Radio waves come in a variety of lengths, from as short as an inch or less up to several miles. The waves we usually think of as radio waves, the ones that broadcast music and weather reports, range in length from about 10 feet for FM to about 300 yards for AM stations.

Astronomers Find Elusive Primeval Galaxies

PASADENA—A group of astronomers has identified the most distant population of normal galaxies yet found. Using a new technique designed to isolate large numbers of extremely distant, young galaxies, the scientists have discovered what are very likely the progenitors of the bright galaxies—spirals and ellipticals—seen today. They observed the galaxies at a time very soon after they first formed, roughly 10 billion years ago, at redshifts between 3.0 and 3.5.

Scientists Report Interactions Between Individual Photons: First Step Toward a Quantum Computer

PASADENA—Caltech physicists have demonstrated that individual photons, which normally do not interact, can strongly influence each other when brought together with an atom inside an optical cavity.

This result—interactions between single photons—could be used to make information processing devices that employ quantum-mechanical effects to improve their performance. Further, these devices could form the building blocks needed to construct a "quantum computer," a theoretical machine that, researchers believe, could outperform any computer based on conventional technology.

Physicists Observe Alteration in Fundamental Interaction of Light and Matter

PASADENA—Scientists recently reported the first experimental observation of the modification of the fundamental interaction between light and matter, a change brought about by illuminating trapped cesium atoms with manifestly quantum, or nonclassical, light.

Scientists refer to the interplay of light and matter as fundamental atomic radiative processes. These processes span the range from the linear absorption and scattering familiar from everyday optics to nonlinear interactions on which for example the laser is based.

Astronomers Announce Discovery of Extremely Distant Quasars

PASADENA—Astronomers have discovered 16 new extremely distant quasars, the result of a search made nearly 40 times more efficient than previously possible by applying artificial intelligence to the new Palomar digital sky survey. This novel technique allows researchers to study more easily the formation of quasars and large-scale structures in the early universe.

"This is one of the first successful major applications of artificial intelligence techniques in astronomy and space science," said Usama Fayyad, a scientist at the Jet Propulsion Laboratory (JPL) in Pasadena, California.

Astronomers Announce Discovery of an Old Brown Dwarf

PASADENA—Astronomers at the California Institute of Technology and the Johns Hopkins University today announce the discovery of what they believe is a brown dwarf, and release the first image and spectrum ever taken of this elusive type of object.

The brown dwarf, called GL 229B, lies in the southern-hemisphere constellation Lepus, near Orion, where it orbits a small, dim star called GL 229. This is the first detection of such a cool object outside the solar system.

Question of the month: How do we remember?

What happens to your brain when you remember something?

Caltech Science Question of the Month: When Do Plants Flower?

Question: How does a plant "know" when it is time to bloom? Answer: Many factors work together to "tell" a plant when it is time to flower, including the amount of food and water available, light, temperature, and a plant's age. But just how a plant senses many of these things remains a puzzle.

Biologists Find Roundworm Protein Similar to Human Cancer Protein

A team of biologists has found a striking similarity between a protein found in roundworms and a common but puzzling protein in humans that is sometimes involved in the growth of cancer. This link, reported in the August 25 issue of the journal Science, will help scientists who study human cancer genes direct their research in more promising directions.

Caltech Observatory Sees Start of New Solar Sunspot Cycle

The first sunspot in the new sunspot cycle was identified on Saturday, August 12, by astronomers at the California Institute of Technology's Big Bear Solar Observatory in Big Bear City, California.

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