← Back to dex
Rare variable star 39 EP

HR 1217

RA 58.8172° · Dec -12.0991° · star

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 6 badges
39 pts · Rare
Rare 50 pts → Epic
  • Fades out of naked-eye view +16
  • Naked-eye visible +8
  • Variable star +5
  • White A-type star +5
  • A named variable star +3
  • Barely variable (under 0.05 mag) +2
Total score 39

11 more points to reach Epic.

Badges

  • Variable star · +5
  • Naked-eye visible · +8
  • White A-type star · +5
  • Barely variable (under 0.05 mag) · +2
  • Fades out of naked-eye view · +16
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads Ap SrEu(Cr) — 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.
  • 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.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around November — 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. ≈ 2.8 million years at Voyager 1's speed (17 km/s).

Properties

absmag
2.53
bv
0.323
constellation
Eri
dist ly
160.5098
luminosity
8.4723
mag
5.99
name
HR 1217
spect
Ap SrEu(Cr)
var amplitude
0.04
var designation
DO
var max
5.975
var min
6.015

About HR 1217

HR 1217 is a rare variable star. It lies about 160.5 light-years from Earth, sits in the constellation Eri, shines at apparent magnitude 5.99 and has spectral type Ap SrEu(Cr).

Its spectrum reads Ap SrEu(Cr) — 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 1217 in the constellation Eri. At apparent magnitude 5.99, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 1217 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 1217 is a rare variable star

HR 1217 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Naked-eye visible, White A-type star, Barely variable (under 0.05 mag), 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.