Stories by David Appell

New data reinforces the notion that these exotic stellar corpses are among the universe’s most perfect spheres

The Texas-based high-energy accelerator would have easily found the Higgs and been capable of searching for still more evidence of new physics

A space-travel technology, simple in concept, has been frustratingly difficult to realize

After engineers run a months-long setup of the Mars Science Laboratory, now parked in a crater, scientists will take the rover on a nearly two-year journey that includes a visit to a six-kilometer-high mountain

A new analysis creates a better look at rising temperatures

Do minor errors erode public support on climate issues?

As the world warms up, some species cannot move to cooler climes in time to survive. Camille Parmesan thinks humans should help even if it means creating invasive species

Planck mission promises to pierce inflation and other cosmic secrets

Researchers debate whether Earth will be swallowed by the sun as it expands into a red giant billions of years from now

Ten years ago two teams discovered that the universe will expand forever at an ever faster rate, thanks to an unseen energy. The leader of one of the groups, Saul Perlmutter, expects that new observations will soon illuminate the universe's dark side

Dark energy is pushing the universe apart at an ever faster rate. Astrophysicist Saul Perlmutter recounts the experimental approaches he took to make that discovery

Carbon-fiber composites could lead to quick fixes for old bridges

Recycling rules vary for mercury-containing fluorescents

After natural disasters, an anxious public wants to see that someone understands the catastrophe. For California quakes, seismologist Lucy Jones does the job

Seven years ago Michael Mann introduced a graph that became an iconic symbol of humanity's contribution to global warming. He has been defending his science ever since

With the success of twin rovers on the Red Planet, Steven W. Squyres and his team are showing how to conduct robotic missions--and setting the stage for human exploration

Less sun at the Earth's surface complicates climate models

Seeking the densest matter: the color glass condensate

Hopes for a giant collider lie in a worldwide appeal

A claim of nonhuman-induced global warming sparks debate

A claim of nonhuman-induced global warming sparks debate

In curbing greenhouse gas emissions, states go it alone

Economist Jeffrey D. Sachs thinks the science and technology of resource-rich nations can abolish poverty, sickness and other woes of the developing world