Measuring the Universe
This abbreviation stands for Astronomical Unit.
What is AU?
This star is at the center of our solar system.
What is the Sun?
These three letters stand for International Space Station.
What is the ISS?
A star is a giant ball of hot gas that produces its own light and this.
What is heat/energy?
Earth completes one rotation in approximately this amount of time.
What is 24 hours?
One AU is approximately this many million kilometers.
What is 150 million kilometers?
These four planets are the inner planets: Mercury, Venus, Earth, and this planet.
Answer: What is Mars?
What is Mars?
Astronauts appear to float on the ISS because they experience this condition.
What is microgravity?
This process in a star’s core releases enormous amounts of energy.
What is nuclear fusion?
Earth’s axis is tilted approximately this many degrees.
What is 23.5°?
This unit measures the distance light travels in one year.
What is a light-year?
This planet is famous for its Great Red Spot.
What is Jupiter?
Humans need this gas to breathe both on Earth and in space.
What is oxygen?
This giant cloud of gas and dust can be the birthplace of a star.
What is a nebula?
Earth completes one revolution around the Sun in approximately this many days.
What is 365.25 days?
Sunlight takes approximately this long to reach Earth.
What is 8 minutes and 20 seconds?
This planet is best known for its large, visible ring system.
What is Saturn?
Astronauts exercise regularly in space to reduce the loss of these two body tissues.
What are muscle and bone?
A massive star may explode in this spectacular event near the end of its life.
What is a supernova?
This combination causes Earth’s seasons.
What are Earth’s axial tilt and revolution around the Sun?
When we observe extremely distant objects, we are actually seeing them as they appeared at this time.
What is the past?
This former ninth planet is now classified as a dwarf planet.
What is Pluto?
Astronauts and the ISS appear weightless because they are continuously doing this around Earth.
What is orbiting/falling around Earth?
A very massive star may eventually collapse into this object with gravity so strong that even light cannot escape.
What is a black hole?
Locations near this imaginary line receive relatively consistent direct sunlight throughout the year.
What is the equator?