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Common star 18 EP

HR 3720

RA 139.3550° · Dec -74.8943° · star

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Score breakdown

· 4 badges
18 pts · Common
Common 22 pts → Uncommon
  • Naked-eye visible +8
  • White A-type star +5
  • Star +3
  • Main-sequence star +2
Total score 18

4 more points to reach Uncommon.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • White A-type star · +5
  • Main-sequence star · +2

Trivia

What it actually is

  • Spectral class. Its spectrum reads A1V — 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 5.3 you can see it with your own eyes from a dark site, over in Carina.
  • Southern sky only. So far south it never rises for most of the northern hemisphere. To see it you'd have to travel to Chile, South Africa or Australia.
  • Best time of year. It stands highest in the middle of the night around February — 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. ≈ 6.2 million years at Voyager 1's speed (17 km/s).

Properties

absmag
0.122
bv
0.021
constellation
Car
dist ly
350.7054
luminosity
77.8395
mag
5.28
name
HR 3720
spect
A1V

About HR 3720

HR 3720 is a common star. It lies about 350.7 light-years from Earth, sits in the constellation Car, shines at apparent magnitude 5.28 and has spectral type A1V.

Its spectrum reads A1V — 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 3720 in the constellation Car. At apparent magnitude 5.28, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 3720 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 3720 is a common star

HR 3720 scores 18 points on Spacedle's rarity scale, which places it in the common tier. Another 4 points would lift it into a rarer tier.

That score comes from 4 science badges — Star, Naked-eye visible, White A-type star and Main-sequence 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.