← Back to dex
Uncommon galaxy 30 EP

NGC 4559

RA 188.9902° · Dec 27.9600° · openngc

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 4 badges
30 pts · Uncommon
Uncommon 34 pts → Rare
  • Galaxy +14
  • Outside our galaxy entirely +6
  • Spiral galaxy +5
  • Big on the sky +5
Total score 30

4 more points to reach Rare.

Badges

  • Galaxy · +14
  • Outside our galaxy entirely · +6
  • Spiral galaxy · +5
  • Big on the sky · +5

Trivia

What it actually is

  • What it actually is. A galaxy: a gravitationally bound city of stars, gas and dark matter, turning so slowly that a single rotation takes hundreds of millions of years.
  • Spiral. A spiral galaxy. Those arms are not solid structures but traffic jams — density waves that stars drift into and out of as they orbit.

Sense of scale

  • In perspective. Further than Andromeda, the most distant thing the unaided human eye can see.
  • Scale. Home to hundreds of billions of stars — a universe unto itself, and every one of those points of light could have planets.

Find it in the sky

  • How to spot it. At magnitude 9.9 you'll want a small backyard telescope, over in Coma Berenices.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around March — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

constellation
Com
dist ly
37980199.5978
dso type
G
hubble
Sc
mag
9.92
name
NGC 4559
radial velocity kms
814
redshift
0.0027
size arcmin
10.57
surface brightness
23.48

About NGC 4559

NGC 4559 is an uncommon galaxy. It lies about 37,980,199.6 light-years from Earth, sits in the constellation Com and shines at apparent magnitude 9.92.

A galaxy: a gravitationally bound city of stars, gas and dark matter, turning so slowly that a single rotation takes hundreds of millions of years.

How to see it

Look for NGC 4559 in the constellation Com. At apparent magnitude 9.92, a small backyard telescope will bring it into view.

Like any astronomical target, NGC 4559 is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why NGC 4559 is an uncommon galaxy

NGC 4559 scores 30 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Galaxy, Outside our galaxy entirely, Spiral galaxy and Big on the sky — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.