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Common star 15 EP

HD 249798

RA 89.5687° · Dec 11.1065° · star

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Score breakdown

· 3 badges
15 pts · Common
Common 22 pts → Uncommon
  • In Orion's hunting ground +6
  • Hot blue B-type star +6
  • Star +3
Total score 15

7 more points to reach Uncommon.

Badges

  • Star · +3
  • In Orion's hunting ground · +6
  • Hot blue B-type star · +6

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9 — 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 9.6 you'll want a small backyard telescope, over in Orion.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around December — 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. ≈ 11.5 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 1 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
3.135
bv
0.087
constellation
Ori
dist ly
652.312
luminosity
4.8529
mag
9.64
name
HD 249798
spect
B9

About HD 249798

HD 249798 is a common star. It lies about 652.3 light-years from Earth, sits in the constellation Ori, shines at apparent magnitude 9.64 and has spectral type B9.

Its spectrum reads B9 — 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 HD 249798 in the constellation Ori. At apparent magnitude 9.64, a small backyard telescope will bring it into view.

Like any astronomical target, HD 249798 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 249798 is a common star

HD 249798 scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 3 science badges — Star, In Orion's hunting ground and Hot blue B-type 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.