Astronomy & Space Why some meteor showers return at nearly the same time every year
IntroductionMeteor showers appear to return at nearly the same time each year because Earth crosses the same streams of ...
Astronomy & Space
Astronomy & Space 
Astronomy & Space Why some planets have rings while others do not
IntroductionPlanetary rings are striking features in our Solar System and beyond: thin, flat bands of dust, ice, and roc...
Astronomy & Space The long journey of a tiny rock before it becomes a meteor
IntroductionEvery meteor that streaks across the sky begins life as a tiny rock that has a long, complex journey through...
Astronomy & Space How tidal forces can stretch and heat entire worlds
IntroductionTidal forces are a gravitational effect that can literally stretch and heat planets, moons, and other celest...
Astronomy & Space How Saturn’s rings can be enormous yet remarkably thin
IntroductionSaturn’s rings look like a bright, flat pancake around the planet — enormous in diameter yet astonishingly t...
Astronomy & Space Why the Moon looks huge near the horizon
IntroductionThe Moon often looks much larger and more dramatic when it is near the horizon than when it is high in the s...
Astronomy & Space Why Saturn’s largest moon has lakes but almost no liquid water
IntroductionTitan, Saturn’s largest moon, surprised scientists by showing clear surface lakes and seas — yet these pools...
Astronomy & Space How ancient starlight reveals what the universe was like long ago
IntroductionWhen you look up at the night sky, you are seeing light that started its journey long before you were born. ...
Astronomy & Space The hidden journey sunlight takes before leaving the Sun
IntroductionThe visible sunlight that warms Earth begins as energy deep inside the Sun. That energy follows a long, comp...
Astronomy & Space The surprisingly complicated shapes of small worlds in space
IntroductionThe small worlds of our solar system — asteroids, dwarf planets, and small moons — come in an astonishing va...