Did you know galaxies are moving away from us?
Image: Walter Rademacher, derivative work Lämpel, CC BY-SA 3.0, via Wikimedia Commons
Edwin Hubble showed galaxies recede with a velocity proportional to their distance
Did you know galaxies are moving away from us?
Imagine you're standing in a field and notice that as you walk further away from a friend, they seem to move farther away too.
Edwin Hubble discovered that galaxies are moving away from us faster the farther they are. This is because the universe is expanding, like blowing up a balloon (Hubble's Law).
Example
If you and your friend are 10 meters apart and you walk 5 meters away, your friend seems to move 10 meters away too.
Remember this
The universe is expanding, causing galaxies to recede from us as they get farther apart.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
Related concepts
Dark matter
Vera Rubin's galaxy rotation curves provided the strongest early evidence that most matter in the universe is invisible
Henrietta Swan Leavitt
Henrietta Leavitt discovered the period-luminosity relation of Cepheid variables
Albert Einstein
How does light behave around massive objects like stars?
Stellar black hole
Ever wondered why nothing escapes a black hole's pull?
Black hole
Stephen Hawking predicted black holes radiate energy and slowly evaporate — Hawking radiation
The Fibonacci sequence appears in sunflower seed patterns, pinecones, and galaxy spirals
Did you know math patterns can grow like plants?
Swipe through 100 ML concepts daily
Open Pocket Polymath