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Uncommon star 28 EP

HR 1803

RA 81.4459° · Dec 0.5202° · star

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Score breakdown

· 6 badges
28 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • In Orion's hunting ground +6
  • Hot blue B-type star +6
  • Blue-white star +5
  • Star +3
  • Main-sequence star +2
Total score 28

6 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • In Orion's hunting ground · +6
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2.5V — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.

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 6.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Orion.
  • Seen from everywhere. It sits almost on the celestial equator, so it can be seen from essentially anywhere on Earth.
  • 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. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 21.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.72
bv
-0.178
constellation
Ori
dist ly
1240.1368
luminosity
424.6196
mag
6.18
name
HR 1803
spect
B2.5V

About HR 1803

HR 1803 is an uncommon star. It lies about 1,240.1 light-years from Earth, sits in the constellation Ori, shines at apparent magnitude 6.18 and has spectral type B2.5V.

Its spectrum reads B2.5V — 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 1803 in the constellation Ori. At apparent magnitude 6.18, it is an easy target for binoculars.

Like any astronomical target, HR 1803 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 1803 is an uncommon star

HR 1803 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 6 science badges — Star, Distant (over 1,000 light-years), In Orion's hunting ground, Hot blue B-type star, Main-sequence 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.