About Herschel's Jewel Box
Herschel's Jewel Box is a rare cluster. It sits in the constellation Cru.
An open cluster: a few hundred stars born together out of one collapsing cloud, still drifting along in loose formation.
Rare cluster 36 EP
Herschel's Jewel Box
RA 193.4045° · Dec -60.3563° · openngc
Score breakdown
· 5 badgesRare 50 pts → Epic
- Coming towards us +10
- Has a proper name +8
- Under the Southern Cross +8
- Star cluster +7
- Open cluster +3
Total score 36
14 more points to reach Epic.
Badges
- Star cluster · +7
- Has a proper name · +8
- Open cluster · +3
- Under the Southern Cross · +8
- Coming towards us · +10
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
- 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
- Where to look. You'll find it in the constellation 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.
Its true colour
- Its true colour. Open clusters look blue-white because they are young — their hottest, bluest stars have not had time to die yet.
What's in a name
- Named. Notable enough to have earned a proper name, not just a catalogue number.
How we came to know it
- The New General Catalogue. Its NGC number comes from J. L. E. Dreyer's 1888 catalogue, itself built on decades of sky sweeps by William Herschel and his sister Caroline.
Properties
- aliases
- kappa Crucis Cluster
- constellation
- Cru
- dso type
- OCl
- name
- Herschel's Jewel Box
- named
- yes
- radial velocity kms
- -20
- size arcmin
- 7.8
Nearby objects
How to see it
Look for Herschel's Jewel Box in the constellation Cru.
Like any astronomical target, Herschel's Jewel Box 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 Herschel's Jewel Box is a rare cluster
Herschel's Jewel Box scores 36 points on Spacedle's rarity scale, which places it in the rare tier. Another 14 points would lift it into a rarer tier.
That score comes from 5 science badges — Star cluster, Has a proper name, Open cluster, Under the Southern Cross and Coming towards us — 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.