In the next decade, when scientists are able to study Earth-sized worlds around other stars, they may find that foliage on some of the planets is predominantly yellow—or orange, or red. It all depends on the color of the star the planet orbits and the stuff that makes up the planet's atmosphere.

On a campus where scientific research can be pretty challenging for the uninitiated, Mike Brown's search for new bodies in the outer solar system is as refreshingly straightforward as, well, the brightly colored marble spheres that sit on his shelf. Each sphere represents a Kuiper-belt object he has found in the last few years, including Eris, which led to the demotion of Pluto to the status of "dwarf planet."

In the outer reaches of the solar system, there is an object known as 2003 EL61 that looks like and spins like a football being drop-kicked over the proverbial goalpost of life.

A team of astronomers led by Carl Grillmair of the California Institute of Technology has discovered some puzzling things about a Jupiter-sized planet that passes in front of a nearby star in the constellation Vulpecula.

Geologists have uncovered evidence in the oil fields of Oman that explains how Earth could suddenly have changed 540 million years ago to favor the evolution of the single-celled life forms to the multicellular forms we know today.

Research by the California Institute of Technology, the University of Southern California, and Indonesian scientists indicates that within the next few decades another big tsunami could flood densely populated sections of western coastal Sumatra, south of those that suffered from the tsunami of December 2004.

Two and a half billion years ago, when our evolutionary ancestors were little more than a twinkle in a bacterium's plasma membrane, the process known as photosynthesis suddenly gained the ability to release molecular oxygen into Earth's atmosphere, causing one of the largest environmental changes in the history of our planet. The organisms assumed responsible were the cyanobacteria, which are known to have evolved the ability to turn water, carbon dioxide, and sunlight into oxygen and sugar, and are still around today as the blue-green algae and the chloroplasts in all green plants.

The recent devastations caused by earthquakes in south and southwest Asia, by the Indian Ocean tsunami, and by hurricane Katrina offer dramatic proof that communities all over the world are both unaware of, and unprepared for, natural hazards. Unfortunately, while scientists understand much about these natural hazards, that knowledge commonly is not used to reduce the risks.

The International Astronomical Union (IAU) today announced that the dwarf planet known as Xena since its 2005 discovery has been named Eris, after the Greek goddess of discord.

The International Astronomical Union (IAU) today downgraded the status of Pluto to that of a "dwarf planet," a designation that will also be applied to the spherical body discovered last year by California Institute of Technology planetary scientist Mike Brown and his colleagues. The decision means that only the rocky worlds of the inner solar system and the gas giants of the outer system will hereafter be designated as planets.