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Epic variable star 59 EP

HR 2855

RA 111.7478° · Dec -23.0860° · star

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Score breakdown

· 9 badges
59 pts · Epic
Epic 78 pts → Anomaly
  • Bright giant +12
  • Intrinsically luminous (Mv < −2) +10
  • Naked-eye visible +8
  • Distant (over 1,000 light-years) +6
  • Hot blue B-type star +6
  • Variable star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
Total score 59

19 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Bright giant · +12
  • Blue-white star · +5
  • Intrinsically luminous (Mv < −2) · +10
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B1II — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.
  • Where it is in life. It is a bright giant, well on its way to the largest stars there are.
  • 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 5.7 you can see it with your own eyes from a dark site, over in Canis Major.
  • 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 January — that's when to go looking.

Could we get there?

  • Verdict. Impossible with our current technology — and the next millennium of it.

Properties

absmag
-2.267
bv
-0.134
constellation
CMa
dist ly
1249.64
luminosity
702.7486
mag
5.65
name
HR 2855
spect
B1II
var amplitude
0.11
var designation
FY
var max
5.61
var min
5.72

About HR 2855

HR 2855 is an epic variable star. It lies about 1,249.6 light-years from Earth, sits in the constellation CMa, shines at apparent magnitude 5.65 and has spectral type B1II.

Its spectrum reads B1II — a blue-white B-type star, with a surface tens of thousands of degrees hot and a life measured in tens of millions of years.

How to see it

Look for HR 2855 in the constellation CMa. At apparent magnitude 5.65, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, HR 2855 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 2855 is an epic variable star

HR 2855 scores 59 points on Spacedle's rarity scale, which places it in the epic tier. Another 19 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, Hot blue B-type star, Bright giant, Blue-white star, Intrinsically luminous (Mv < −2) and Gently variable — 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.