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Epic star 50 EP

HD 152405

RA 253.7307° · Dec -40.5248° · star

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Score breakdown

· 4 badges
50 pts · Epic
Epic 78 pts → Anomaly
  • Blazing O-type star +26
  • Supergiant +18
  • Star +3
  • On the zodiac +3
Total score 50

28 more points to reach Anomaly.

Badges

  • Star · +3
  • On the zodiac · +3
  • Blazing O-type star · +26
  • Supergiant · +18

Trivia

What it actually is

  • Spectral class. Its spectrum reads O9.5Ib — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.
  • Where it is in life. It is a supergiant, hundreds of times wider than the Sun.

Find it in the sky

  • How to spot it. At magnitude 7.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Scorpius.
  • 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 June — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out brilliant white (B−V 0.1) — hotter and whiter than the Sun, the colour of Sirius or Vega.
  • Why no green stars. No star ever looks green: a surface hot enough to peak in green also floods out plenty of red and blue, and your eye blends the mixture back to white.

By the numbers

  • Surface temperature. Its colour puts the surface at roughly 9160 K, against the Sun's 5778 K.

Properties

absmag
-12.8
bv
0.087
constellation
Sco
luminosity
11481536.215
mag
7.2
name
HD 152405
spect
O9.5Ib

About HD 152405

HD 152405 is an epic star. It sits in the constellation Sco, shines at apparent magnitude 7.2 and has spectral type O9.5Ib.

Its spectrum reads O9.5Ib — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

How to see it

Look for HD 152405 in the constellation Sco. At apparent magnitude 7.2, it is an easy target for binoculars.

Like any astronomical target, HD 152405 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 HD 152405 is an epic star

HD 152405 scores 50 points on Spacedle's rarity scale, which places it in the epic tier. Another 28 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, On the zodiac, Blazing O-type star and Supergiant — 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.