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Epic variable star 61 EP

55 Eri

RA 70.8948° · Dec -8.7943° · star

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Score breakdown

· 9 badges
61 pts · Epic
Epic 78 pts → Anomaly
  • Fades out of naked-eye view +16
  • Intrinsically luminous (Mv < −2) +10
  • Naked-eye visible +8
  • Distant (over 1,000 light-years) +6
  • Giant star +6
  • Variable star +5
  • Gently variable +4
  • Yellow-white F-type star +3
  • A named variable star +3
Total score 61

17 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Naked-eye visible · +8
  • Yellow-white F-type star · +3
  • Giant star · +6
  • Intrinsically luminous (Mv < −2) · +10
  • Gently variable · +4
  • Fades out of naked-eye view · +16
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads F4IIIp (Sr) — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • Where it is in life. It is a giant. It has already exhausted its core hydrogen and swollen up enormously in response.
  • 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 you can see it with your own eyes from a dark site, over in Eridanus.
  • 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.

Properties

absmag
-3.097
bv
0.645
constellation
Eri
dist ly
2131.7387
luminosity
1509.3849
mag
5.98
name
55 Eri
spect
F4IIIp (Sr)
var amplitude
0.09
var designation
DW
var max
5.951
var min
6.041

About 55 Eri

55 Eri is an epic variable star. It lies about 2,131.7 light-years from Earth, sits in the constellation Eri, shines at apparent magnitude 5.98 and has spectral type F4IIIp (Sr).

Its spectrum reads F4IIIp (Sr) — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for 55 Eri in the constellation Eri. At apparent magnitude 5.98, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 55 Eri 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 55 Eri is an epic variable star

55 Eri scores 61 points on Spacedle's rarity scale, which places it in the epic tier. Another 17 points would lift it into a rarer tier.

That score comes from 9 science badges — Variable star, Distant (over 1,000 light-years), Naked-eye visible, Yellow-white F-type star, Giant star, Intrinsically luminous (Mv < −2), Gently variable and Fades out of naked-eye view — 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.