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Uncommon galaxy 28 EP

NGC 3138

RA 152.3195° · Dec -11.9567° · openngc

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Score breakdown

· 4 badges
28 pts · Uncommon
Uncommon 34 pts → Rare
  • Galaxy +14
  • Outside our galaxy entirely +6
  • Spiral galaxy +5
  • Faint fuzzy (mag > 13) +3
Total score 28

6 more points to reach Rare.

Badges

  • Galaxy · +14
  • Outside our galaxy entirely · +6
  • Spiral galaxy · +5
  • Faint fuzzy (mag > 13) · +3

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. Deep in the extragalactic distance — further than the entire Virgo Cluster of galaxies.
  • 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 15.6 it is far too faint for the eye: this one belongs to cameras and long exposures, over in Hydra.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around February — that's when to go looking.

Could we get there?

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

Properties

constellation
Hya
dist ly
369199946.881
dso type
G
hubble
Sbc
mag
15.58
name
NGC 3138
radial velocity kms
7819
redshift
0.0264
size arcmin
1.1
surface brightness
23.32

About NGC 3138

NGC 3138 is an uncommon galaxy. It lies about 369,199,946.9 light-years from Earth, sits in the constellation Hya and shines at apparent magnitude 15.58.

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 3138 in the constellation Hya. At apparent magnitude 15.58, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, NGC 3138 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 3138 is an uncommon galaxy

NGC 3138 scores 28 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 6 points would lift it into a rarer tier.

That score comes from 4 science badges — Galaxy, Outside our galaxy entirely, Spiral galaxy and Faint fuzzy (mag > 13) — 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.