The first quasar to be understood (1963): the blazing core of a distant galaxy, powered by a supermassive black hole swallowing gas.
You see 3C 273 as it was about 2 billion years ago.
| Distance from us | about 2 billion light-years |
|---|
We use about 2 billion light-years: the time its light has been on the way, worked out from its redshift (NED, z = 0.1583) with the Planck 2018 values for the expanding universe. The 2.4 or 2.5 billion often quoted are other kinds of distance.
It belongs to a giant elliptical galaxy — the quasar is that galaxy’s blazing core, so far away the rest of it is lost in the glare.
The Milky Wayspiral galaxyNaked eye
The Andromeda Galaxy (M31)spiral galaxyNaked eyeThe Triangulum Galaxy (M33)spiral galaxyBinoculars
The Large Magellanic Cloudirregular galaxyNaked eyeBode’s Galaxy (M81)spiral galaxyBinocularsThe Whirlpool Galaxy (M51)spiral galaxy150 mm telescope
Show 3C 273 in the model
About
Space
Planetarium
How far is the horizon?
What happens when you zoom out
When a picture squashes the numbers
Measuring the sky with your hand
Why a day is longer than one spin — on most planets
Does the Moon go round the Earth?
Why the sea goes up and down
A catalogue of everything
Stars that change brightness
How a star is born, and the ways it can end
How the universe began, and how anyone could know
Where a space telescope parks · the Lagrange points
Where does the solar system end?
The cosmic distance ladder, in one page
1 · The size of the Earth
2 · The size and distance of the Moon
3 · How the solar system is arranged
4 · The distance to the Sun and planets
5 · The distance to nearby stars
6 · The distance to other galaxies
7 · The scale of the universe
What is left to explain
What this site does not cover
Everything in the sky