Only five percent of our universe is composed of visible matter, stars, planets and people; something called "dark matter" makes up about 25 percent and an enormous 70 percent of the universe is pervaded with "dark energy". Scientists had predicted a Big Crunch as the logical opposite of the Big Bang, but far from retracting, the expansion of the universe is actually accelerating. How do we know that ... Full description.

This audio interview with theoretical physicist Lisa Randall discusses higher dimensional spacetime and other ideas from her book, "Warped Passages: Unraveling The Mysteries Of The Universe's Hidden Dimensions". There is discussion of visualizing higher dimensions by using lower dimensions, string theory and the Large Hadron Collider, how to find new physics to explain dark energy, and the incompatibility ... Full description.

In 1999, New York planned to bring suit against seventeen midwestern power plants, seeking reductions in ozone, VOC (volatile organic compounds) and NOx (nitrogen oxides) emissions. The suits hinged on allegations that the plants have increased their operating capacity without upgrading emission controls as required by the Clean Air Act. The issue of trans-boundary air pollution has long been a contentious ... Full description.

Scientists say the aurora, or northern lights, offer the chance to study high-frequency plasma waves that occur in the ionosphere. This radio broadcast reports on rockets that are fired into the Alaskan aurora to measure density and magnetic fields in the atmospheric plasma. The rockets will improve understanding of the Earth, the atmosphere, and plasma physics. The clip is 4 minutes in length. Full description.

How and when did the first living creatures crawl up onto land and what were the first terrestrial animals like? This radio broadcast tracks down the little arthropods, whose trackways have been discovered in the ancient sandstones of Ontario in Canada; these trackways date back 500 million years and offer the earliest evidence so far of animals coming onto land for the first time. These creatures ... Full description.

This radio broadcast explains how stars form from clouds of gas called proto-stars. As well, it explains how the lifetime of stars can be estimated from knowing their fuel type and luminosity. There is explanation of what happens when a star runs out of hydrogen fuel: how it cools and begins to collapse, burning different elements until it contains an iron core. The broadcast finally discusses the ... Full description.

This radio broadcast reports on ways to put ocean water to work doing everything from running steam engines and providing electricity to providing air conditioning and growing marine life and vegetables. After harnessing the power of the sea, the water is still clean and can be returned to the ocean. The clip is 2 minutes in length. Full description.

This broadcast describes the four great Eons of history: the Hadean, the Archean, the Proterozoic and the Phanerozoic. Together, they encompass four and a half billion years. How can we begin to make sense of such a huge swathe of time? And can we be sure that we have got the age of the Earth right? Geologists use Eras, Periods and Epochs to further punctuate what is known as Deep Time, but can we ... Full description.

Is the universe chaotic or orderly? According to chaos theory, the world is far more complicated than was previously thought. Instead of the future of the universe being irredeemably fixed, we are, in fact, subject to the whims of random unpredictability due to this complexity. This radio broadcast discusses how patterns are found in the meeting of order and disorder, such as the fractal patterns ... Full description.

This radio broadcast consists of a two-part radio interview with a seal researcher in Antarctica aboard the National Science Foundation research ship Nathaniel B. Palmer in 2000. The first interview discusses the seal populations found in Antarctica and how they are distributed, and the differences between the four seal species found in Antarctica. The second interview describes life on the ship, ... Full description.