Planetary Science
16 questions tagged Planetary Science — spanning every one of the seven Ws.
Why Does the Moon Always Show the Same Face?
The Moon is tidally locked to Earth — its rotation period exactly matches its orbital period (about 27.3 days), so the same hemisphere always faces us.
Which Planet Has the Strongest Winds?
Neptune has the strongest measured winds in the solar system, with speeds reaching approximately 2,100 km/h (580 m/s) — despite being the farthest planet from the Sun and receiving very little solar energy.
Which Planet Has the Most Extreme Weather?
Jupiter has arguably the most extreme weather in the solar system: its Great Red Spot is a storm larger than Earth that has raged for at least 350 years, with wind speeds exceeding 640 km/h.
Why does the Earth have an oblate shape instead of a perfect sphere?
Earth bulges at the equator because its rotation creates centrifugal effects that oppose gravity most strongly there. The planet’s equatorial diameter is about 43 km larger than its polar diameter.
Which is the largest known volcano in the Solar System?
Olympus Mons on Mars is the largest known volcano in the Solar System. It rises about 22 kilometers above the surrounding plains and is roughly 600 kilometers wide.
Which planet has the most extreme temperature differences?
Mercury has the most extreme temperature swings among the planets, with scorching daytime highs and freezing nighttime lows.
Why is the Earth getting a little heavier every day from space dust?
Earth gains a small amount of mass from meteoroids and cosmic dust constantly falling through the atmosphere. Most incoming material is tiny, and much of it burns up before reaching the ground.
Which force dominates the motion of planets around stars?
Gravity dominates the motion of planets around stars. It keeps planetary systems bound and determines orbital paths.
Whose work first recognized that meteorite impacts can shape planetary geology?
Gene Shoemaker made impact cratering a major field of study. He showed that many lunar and planetary craters are impact features.
How do scientists measure the mass of a planet without landing on it?
They track how the planet’s gravity affects nearby objects, such as moons, spacecraft, or other planets. The stronger the pull, the more precisely the mass can be inferred.
When was the first meteorite classified scientifically?
Scientific meteorite classification took shape in the late 18th and early 19th centuries, especially after the 1794 L'Aigle fall was investigated.
Which planet rotates the slowest on its axis?
Venus rotates the slowest of the eight planets, taking about 243 Earth days to complete one rotation. In fact, its day is longer than its year.
Whose work first described the ring structure of Saturn in modern terms?
James Clerk Maxwell proved in 1859 that Saturn's rings could not be solid or fluid, but had to be made of countless small particles. His analysis laid the foundation for ring dynamics.
How do scientists calculate a planet's mass if it has moons?
By measuring how the moon orbits the planet and applying Newton's laws, scientists can work out the planet's mass from the moon's orbital period and distance.
How do scientists measure the length of a planet's day?
They track surface features, clouds, or radio signals over time to see how fast the planet turns.
How does a planet's tilt create seasons?
A tilted axis changes how sunlight falls on different parts of a planet during its orbit, creating seasonal shifts.