An iceberg that likely calved from Jakobshavn Isbrae, the fastest glacier in western Greenland. Ian Joughin/Science/AAAS hide caption

itoggle caption Ian Joughin/Science/AAAS

Can You Tell Emotion From Faces Alone? A new study suggests that when people evaluated just facial expressions — without cues from the rest of the body — they couldn't tell if the face was showing a positive or negative emotion. Enlarge this photo to see the answers. Hillel Aviezer/The Hebrew University of Jerusalem hide caption

itoggle caption Hillel Aviezer/The Hebrew University of Jerusalem

The taste of Mock's tomatoes starts with the seed. He uses only organic varieties, including cherry and several heirloom varieties. Allison Aubrey/NPR hide caption

itoggle caption Allison Aubrey/NPR

Researchers say they have identified traces of ice in craters on Mercury, seen here in this Oct. 8, 2008, image from the Messenger spacecraft. NASA hide caption

itoggle caption NASA

The seeds of this goosefoot plant are known as quinoa, a superfood now in high demand and grown almost exclusively in South America. But some growers think they have the formula to grow it up north. Janet Matanguihan/courtesy Kevin Murphy hide caption

itoggle caption Janet Matanguihan/courtesy Kevin Murphy