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Epic variable star 69 EP

HR 3999

RA 152.3415° · Dec -61.5490° · star

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Score breakdown

· 8 badges
69 pts · Epic
Epic 78 pts → Anomaly
  • Dramatic variable (over 2 magnitudes) +20
  • Fades out of naked-eye view +16
  • Deep red star +8
  • Distant (over 1,000 light-years) +6
  • Red dwarf +6
  • Variable star +5
  • Cool red M-type star +5
  • A named variable star +3
Total score 69

9 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Cool red M-type star · +5
  • Deep red star · +8
  • Red dwarf · +6
  • Dramatic variable (over 2 magnitudes) · +20
  • Fades out of naked-eye view · +16
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads M2/M3e — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.
  • It changes. This star does not hold still: its brightness rises and falls on a rhythm of hours, days or years, either pulsing in size or being eclipsed by a companion.

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 6.9 it is just past naked-eye reach — ordinary binoculars will pull it in, 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. Impossible with our current technology — and the next millennium of it.

Getting there

  • Aboard Voyager 1. ≈ 31.3 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-1.748
bv
1.5
constellation
Car
dist ly
1782.2733
luminosity
435.7125
mag
6.94
name
HR 3999
spect
M2/M3e
var amplitude
3.24
var designation
S
var max
5.315
var min
8.555

About HR 3999

HR 3999 is an epic variable star. It lies about 1,782.3 light-years from Earth, sits in the constellation Car, shines at apparent magnitude 6.94 and has spectral type M2/M3e.

Its spectrum reads M2/M3e — an M-type red star — and M stars are the silent majority: roughly three of every four stars in the galaxy are one.

How to see it

Look for HR 3999 in the constellation Car. At apparent magnitude 6.94, it is an easy target for binoculars.

Like any astronomical target, HR 3999 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 3999 is an epic variable star

HR 3999 scores 69 points on Spacedle's rarity scale, which places it in the epic tier. Another 9 points would lift it into a rarer tier.

That score comes from 8 science badges — Variable star, Distant (over 1,000 light-years), Cool red M-type star, Deep red star, Red dwarf, Dramatic variable (over 2 magnitudes), Fades out of naked-eye view and A named variable 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.