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Common star 19 EP

HR 398

RA 21.4429° · Dec 70.9799° · star

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Score breakdown

· 5 badges
19 pts · Common
Common 22 pts → Uncommon
  • White A-type star +5
  • Blue-white star +5
  • Never sets (northern circumpolar) +4
  • Star +3
  • Main-sequence star +2
Total score 19

3 more points to reach Uncommon.

Badges

  • Star · +3
  • Never sets (northern circumpolar) · +4
  • White A-type star · +5
  • Main-sequence star · +2
  • Blue-white star · +5

Trivia

What it actually is

  • Spectral class. Its spectrum reads A0Vnn — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.
  • 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 6.3 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cassiopeia.
  • Never sets. So far north that from Britain, Canada or northern Europe it never dips below the horizon — it is up every clear night of the year.
  • Best time of year. It stands highest in the middle of the night around October — 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. ≈ 8.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.531
bv
-0.011
constellation
Cas
dist ly
473.376
luminosity
53.4072
mag
6.34
name
HR 398
spect
A0Vnn

About HR 398

HR 398 is a common star. It lies about 473.4 light-years from Earth, sits in the constellation Cas, shines at apparent magnitude 6.34 and has spectral type A0Vnn.

Its spectrum reads A0Vnn — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HR 398 in the constellation Cas. At apparent magnitude 6.34, it is an easy target for binoculars.

Like any astronomical target, HR 398 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 398 is a common star

HR 398 scores 19 points on Spacedle's rarity scale, which places it in the common tier. Another 3 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Never sets (northern circumpolar), White A-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.