The MESSENGER orbiter's January 2008 flyby of the planet Mercury was historic. The last time a spacecraft visited was 1975, and it only mapped half the planet. MESSENGER is now sending back a complete picture of Mercury, shedding light on its geological history. But the ongoing mission will return much more than images. Its data on the planet's core, magnetic field, composition, and other attributes will help scientists answer pressing questions about the evolution of the terrestrial planets and even the Solar System itself. In the feature video, watch the MESSENGER science team react as the orbiter's first images of Mercury roll in. To explore the images in detail, click on the slide show at left. Find out more on the mission by clicking on the essay "First Planet Finishes Last."
In this experiment students will observe two model atmospheres to understand how greenhouse gases absorb and hold heat.
Follow mermaids around the world and throughout history to see first-hand how cultures share and reinterpret mythic creatures.
The elusive giant squid was first described 500 years ago by Scandinavian sailors. Investigate what we've learned--and what still remains unknown--about this mysterious deep-ocean creature.
After having students conduct a simple solar energy experiment, challenge them to build a better water heater with this classroom competition.
Explore your ancestral past and the 22nd-century possibilities of DNA research with this collection of kid-friendly titles selected for the Hall of Human Origins.
What are evolutionary trees? How do hominids differ from primates? And why is it important that humans are capable of symbolic thought? Find out with this guide from "DNA" to "variation."
How safe is the water in Mercer Lake as an occasional play area for local family dogs, including mine? Find out what this young naturalist discovered when he set out to answer that question.
Is a thriving algae population good or bad for a river’s water quality? Find out what this young naturalist discovered when she set out to answer that question.