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Uncommon star 25 EP

HR 2733

RA 108.4516° · Dec -22.9058° · star

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Score breakdown

· 5 badges
25 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Blue-white star +5
  • Star +3
Total score 25

9 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • Hot blue B-type star · +6
  • Subgiant (leaving the main sequence) · +5
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2IV — 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.
  • Where it is in life. It is a subgiant, caught in the act of leaving the main sequence as the hydrogen in its core runs out.

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 6.3 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Canis Major.
  • 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 January — 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. ≈ 25 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.861
bv
-0.184
constellation
CMa
dist ly
1424.2619
luminosity
483.5039
mag
6.34
name
HR 2733
spect
B2IV

About HR 2733

HR 2733 is an uncommon star. It lies about 1,424.3 light-years from Earth, sits in the constellation CMa, shines at apparent magnitude 6.34 and has spectral type B2IV.

Its spectrum reads B2IV — 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 2733 in the constellation CMa. At apparent magnitude 6.34, it is an easy target for binoculars.

Like any astronomical target, HR 2733 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 2733 is an uncommon star

HR 2733 scores 25 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 9 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Distant (over 1,000 light-years), Hot blue B-type star, Subgiant (leaving the main sequence) 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.