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Uncommon star 28 EP

HR 4221

RA 161.7395° · Dec -56.7572° · star

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Score breakdown

· 5 badges
28 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Giant star +6
  • Blue-white star +5
  • Star +3
Total score 28

6 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Giant star · +6
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B8/B9III — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.

Find it in the sky

  • How to spot it. At magnitude 5.1 you can see it with your own eyes from a dark site, over in Vela.
  • 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 March — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 9.2 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 821.4 thousand years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-0.898
bv
-0.08
constellation
Vel
dist ly
526.058
luminosity
199.159
mag
5.14
name
HR 4221
spect
B8/B9III

About HR 4221

HR 4221 is an uncommon star. It lies about 526.1 light-years from Earth, sits in the constellation Vel, shines at apparent magnitude 5.14 and has spectral type B8/B9III.

Its spectrum reads B8/B9III — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for HR 4221 in the constellation Vel. At apparent magnitude 5.14, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 4221 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 HR 4221 is an uncommon star

HR 4221 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 5 science badges — Star, Naked-eye visible, Hot blue B-type star, Giant star and Blue-white star — 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.