Sparticl

How many people in your life have died of an infectious disease? Almost anyone answering that question before the 20th century would have said, "many."

Vaccinations, antibiotics, and hygiene have changed our lives. But the microbes are changing too. New diseases are emerging, as old ones evolve to resist the drugs that used to kill them. Take a look at the fight.

Sunscreen claims to block ultraviolet light. That's good, because UV light waves, which are shorter than the ones our eyes can see, can cause sunburns and skin cancer.

But instruments that display UV light in familiar colors have given scientists new insights into flowers, the Earth, the Sun, even whole galaxies. Now you too can see the universe in a whole new light.

Since we inherit our parents’ genes, how come our sisters and brothers don’t look exactly like us? How come we sometimes look more like our grandparents?

No one could explain heredity at all until a monk started studying pea plants. Nowadays, though, we can see exactly what's happening as living things put some of their genes, but not others, into the cells that become their offspring.

We're facing the next chapter of space exploration, and humans will travel deeper into the solar system than ever before.

Investigate the role commercial ventures play, new vehicles and technologies, and what experts say about meeting the challenges of exploring destinations beyond low Earth orbit.

Imagine you’re sick or injured, but far from the kind of health care you need. Not long ago, you’d have been out of luck.

But now, thanks to computer links and robots, a doctor can examine you, analyze your blood, even operate on you, from miles or even thousands of miles away. Welcome to the new world of telemedicine.