What is a huge, gravity-bound collection of billions of stars called?
Show answer
Galaxy
Our home galaxy is the Milky Way.
💡 Did you know? There are likely hundreds of billions of galaxies.
All questions with answers
What is an object whose gravity is so strong that not even light escapes called?
Show answer
Black hole
Its boundary is the event horizon.
💡 Did you know? In 2019 the first photo of a black hole was taken.
What is the huge explosion of a dying massive star called?
Show answer
Supernova
It can briefly outshine a whole galaxy.
💡 Did you know? Heavy elements like gold form within it.
What is the unit of distance of about 9.46 trillion kilometres called?
Show answer
Light-year
That is about 9.46 trillion kilometres.
💡 Did you know? The nearest star is about 4 light-years away.
What is an icy, dusty “tailed star” with a long glowing tail called?
Show answer
Comet
Halley's Comet returns roughly every 76 years.
💡 Did you know? The tail always points away from the Sun.
What is a small rocky body orbiting the Sun (mostly between Mars and Jupiter) called?
Show answer
Asteroid
Most lie in the asteroid belt.
💡 Did you know? An impact likely wiped out the dinosaurs.
What is an interstellar cloud of gas and dust, often a birthplace of stars, called?
Show answer
Nebula
The Orion Nebula is famous.
💡 Did you know? Some nebulae are supernova remnants.
What is the theory of the universe's beginning about 13.8 billion years ago called?
Show answer
Big Bang
The universe has been expanding ever since.
💡 Did you know? The cosmic background radiation is its echo.
What is a bloated, cool star in a late life stage called?
Show answer
Red giant
Our Sun will become one in billions of years.
💡 Did you know? It may then swallow the inner planets.
What is a world orbiting a star other than the Sun called?
Show answer
Exoplanet
Thousands are already known.
💡 Did you know? Some lie in the “habitable zone”.
What is it called when the Moon blocks the Sun as seen from Earth?
Show answer
Solar eclipse
At totality, day turns to dark.
💡 Did you know? Totality is visible only in a narrow band.
What is our own galaxy, seen at night as a bright band, called?
Show answer
Milky Way
It holds hundreds of billions of stars.
💡 Did you know? It is a spiral galaxy.
How PurFact works
- Every new tab, every visit: one question from your packs.
- What you know comes back at growing intervals; what you don't yet comes back sooner.
- Games, learning paths and duels with friends turn studying into a competition.
Astronomy & Space: all topics →
Home · All topics · Legal notice · Privacy · Terms · Contact