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Rare cluster 38 EP

Coalsack Cluster

RA 190.5701° · Dec -62.9958° · openngc

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Score breakdown

· 6 badges
38 pts · Rare
Rare 50 pts → Epic
  • Has a proper name +8
  • Under the Southern Cross +8
  • Star cluster +7
  • Distant (over 1,000 light-years) +6
  • Bright deep-sky object +6
  • Open cluster +3
Total score 38

12 more points to reach Epic.

Badges

  • Star cluster · +7
  • Distant (over 1,000 light-years) · +6
  • Bright deep-sky object · +6
  • Has a proper name · +8
  • Open cluster · +3
  • Under the Southern Cross · +8

Trivia

What it actually is

  • What it actually is. An open cluster: a few hundred stars born together out of one collapsing cloud, still drifting along in loose formation.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.
  • Sense of scale. Gravity is not strong enough to hold it. Within a few hundred million years these siblings will be scattered right around the galaxy.

Find it in the sky

  • How to spot it. At magnitude 6.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Crux.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • Best time of year. It stands highest in the middle of the night around April — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 86.8 million years at Voyager 1's speed (17 km/s).

Properties

constellation
Cru
dist ly
4941.7576
dso type
OCl
mag
6.9
name
Coalsack Cluster
named
yes
radial velocity kms
22
redshift
0.0001
size arcmin
5.4

About Coalsack Cluster

Coalsack Cluster is a rare cluster. It lies about 4,941.8 light-years from Earth, sits in the constellation Cru and shines at apparent magnitude 6.9.

An open cluster: a few hundred stars born together out of one collapsing cloud, still drifting along in loose formation.

How to see it

Look for Coalsack Cluster in the constellation Cru. At apparent magnitude 6.9, it is an easy target for binoculars.

Like any astronomical target, Coalsack Cluster 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 Coalsack Cluster is a rare cluster

Coalsack Cluster scores 38 points on Spacedle's rarity scale, which places it in the rare tier. Another 12 points would lift it into a rarer tier.

That score comes from 6 science badges — Star cluster, Distant (over 1,000 light-years), Bright deep-sky object, Has a proper name, Open cluster and Under the Southern Cross — 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.