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Rare star 38 EP

The1Sgr

RA 299.9341° · Dec -35.2763° · star

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Score breakdown

· 7 badges
38 pts · Rare
Rare 50 pts → Epic
  • Naked-eye visible +8
  • Toward the galactic centre +8
  • Hot blue B-type star +6
  • Subgiant (leaving the main sequence) +5
  • Blue-white star +5
  • Star +3
  • On the zodiac +3
Total score 38

12 more points to reach Epic.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Toward the galactic centre · +8
  • On the zodiac · +3
  • 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 B2.5IV — 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 4.4 you can see it with your own eyes from a dark site, over in Sagittarius.
  • 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 July — 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. ≈ 9.1 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.637
bv
-0.15
constellation
Sgr
dist ly
518.531
luminosity
393.3689
mag
4.37
name
The1Sgr
spect
B2.5IV

About The1Sgr

The1Sgr is a rare star. It lies about 518.5 light-years from Earth, sits in the constellation Sgr, shines at apparent magnitude 4.37 and has spectral type B2.5IV.

Its spectrum reads B2.5IV — 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 The1Sgr in the constellation Sgr. At apparent magnitude 4.37, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, The1Sgr 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 The1Sgr is a rare star

The1Sgr 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 7 science badges — Star, Naked-eye visible, Toward the galactic centre, On the zodiac, 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.