Space 1
Which planet is known as "the Red Planet"?
Mars
What causes the different phases of the Moon, like a crescent or a full moon?
The phases of the Moon are caused by the changing angles at which we view the Moon's sunlit surface as it orbits Earth.
What is the star at the center of our solar system?
Sun.
What is the largest planet in our solar system?
Jupiter.
What is the glowing streak of light that appears in the night sky as a small space rock enters Earth's atmosphere?
Meteor.
What is the Great Red Spot on Jupiter?
A big storm
Why does a comet's tail always point away from the Sun, even when the comet is moving away from the Sun?
A comet's tail is made of gas and dust that are pushed away from the comet's head by the solar wind and radiation pressure from the Sun.
What is a large, spinning star that has collapsed under its own gravity?
Neutron star.
What is the force that keeps planets in orbit around the Sun?
Gravity.
What are the two planets in our solar system that have no moons?
Mercury, Venus.
What is the difference between a meteor and a meteorite?
A meteor is a space rock that is still in Earth's atmosphere, also known as a "shooting star." A meteorite is a space rock that has survived its passage through the atmosphere and has landed on the surface of Earth.
If there is no sound in the vacuum of space, how do we know the Sun is full of activity and energy?
While we can't hear the Sun directly, we observe its activity through the sound waves traveling through its interior, which cause subtle vibrations on the Sun's surface. Scientists can use special instruments to detect these vibrations and study the Sun's internal structure.
What causes the seasons on Earth?
Tilt.
What is the path a planet takes around a star called?
Orbit.
What is the term for a meteor that survives its fiery passage through the atmosphere and lands on Earth?
Meteorite.
Which famous telescope, launched in 1990, has provided stunning images of distant galaxies, nebulae, and planets?
The Hubble Space Telescope.
What is the Doppler effect in space, and how does it relate to the observation that the universe is expanding?
The Doppler effect is the stretching or compressing of light waves from a moving source. In space, almost all galaxies show a "redshift"—meaning their light waves are stretched—which indicates they are moving away from us. The fact that more distant galaxies are more redshifted provides key evidence that the universe is expanding.
What is the term for a planet outside our solar system?
Exoplanet.
What celestial object has gravity so strong that nothing, not even light, can escape?
Black hole.
What is the theorized process of rapid expansion that the universe underwent shortly after the Big Bang?
Inflation.
What causes the ocean's tides, and why are they stronger at some times than others?
Tides are mainly caused by the Moon's gravity pulling on Earth's oceans, with a smaller effect from the Sun. Tides are strongest during a new or full moon, because the Sun and Moon are aligned and their gravitational pulls combine.
What is the "habitable zone" around a star, and what factors besides distance affect a planet's potential for life?
The "habitable zone" is the orbital region where a planet could have liquid water on its surface. Factors like the planet's atmosphere, volcanic activity, and the star's radiation can also determine if it can actually support life.
What is the theorized dark, cold material making up most of the universe's mass?
Dark matter.
What are the two main elements that make up a star?
Hydrogen, Helium.
What is the name for the point of no return surrounding a black hole, beyond which nothing, not even light, can escape?
Event horizon.