In 1969, an exploding fireball tore through the sky over Mexico, scattering thousands of pieces of meteorite across the state of Chihuahua. More than 40 years later, the Allende meteorite is still serving the scientific community as a rich source of information about the early stages of our solar system's evolution. Recently, scientists from the California Institute of Technology (Caltech) discovered a new mineral embedded in the space rock—one they believe to be among the oldest minerals formed in the solar system.

Were dinosaurs slow and stupid, as used to be the prevailing wisdom, or nimble and smart enough to eat an attorney, as in the 1993 film Jurassic Park? The answer depends largely on whether the T. Rex in question is cold blooded, like an alligator, or warm blooded, like a bird. 

Mike Brown, the Richard and Barbara Rosenberg Professor and professor of planetary astronomy at the California Institute of Technology (Caltech), has been named a co-winner of the 2012 Kavli Prize in Astrophysics for his efforts to understand the outer solar system—work that led to the demotion of Pluto.

Last year, images from NASA's Mars Reconnaissance Orbiter captured sand dunes and ripples moving across the surface of Mars—observations that challenged previously held beliefs that there was not a lot of movement on the red planet's surface. Now, technology developed by a team at the California Institute of Technology (Caltech) has allowed scientists to measure these activities for the very first time. 

Hiroo Kanamori, the John E. and Hazel S. Smits Professor of Geophysics, Emeritus, at Caltech, has been elected one of 21 new foreign associates of the National Academy of Sciences. Eighty-four new members were also announced during the 149th annual meeting of the academy in Washington, D.C. 

By analyzing stalagmites, a team of Caltech researchers has determined that the climate signature in the tropics through four glacial cycles looks different in some ways and similar in others when compared to the climate signature at high latitudes. The results suggest that Earth's climate system might have two modes of responding to significant changes. 

What's it like to build an entire research program from scratch? It's all about becoming part of a community, according to three brand-new professors who chat about their experiences in "From the Ground Up," an article in the Spring 2012 issue of Caltech's Engineering & Science magazine.

The second-largest mass extinction in Earth's history coincided with a short but intense ice age. Although it has long been agreed that the so-called Late Ordovician mass extinction was related to climate change, exactly how the change produced the extinction has not been known. Now, a team led by Caltech scientists has determined that the majority of extinctions were caused by habitat loss due to falling sea levels and cooling of the tropical oceans.

Many of us see a man in the moon—a human face smiling down at us from the lunar surface. The "face," of course, is just an illusion, shaped by the dark splotches of lunar maria (smooth plains formed from the lava of ancient volcanic eruptions). Like a loyal friend, the man is always there, constantly gazing at us as the moon revolves around Earth. But why did the moon settle into an orbit with the man facing Earth?