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Epic variable star 64 EP

HR 2442

RA 99.6591° · Dec 1.6135° · star

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Score breakdown

· 7 badges
64 pts · Epic
Epic 78 pts → Anomaly
  • Blazing O-type star +26
  • Bright giant +12
  • Intrinsically luminous (Mv < −2) +10
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • A named variable star +3
  • Barely variable (under 0.05 mag) +2
Total score 64

14 more points to reach Anomaly.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Blazing O-type star · +26
  • Bright giant · +12
  • Intrinsically luminous (Mv < −2) · +10
  • Barely variable (under 0.05 mag) · +2
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads O9.5II — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.
  • 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 6.2 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Monoceros.
  • 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
-2.89
bv
0.086
constellation
Mon
dist ly
2174.3734
luminosity
1247.3835
mag
6.23
name
HR 2442
spect
O9.5II
var amplitude
0.05
var designation
V689
var max
6.205
var min
6.255

Nearby objects

About HR 2442

HR 2442 is an epic variable star. It lies about 2,174.4 light-years from Earth, sits in the constellation Mon, shines at apparent magnitude 6.23 and has spectral type O9.5II.

Its spectrum reads O9.5II — an O-type star — the hottest, rarest main class there is. Fewer than one star in a million is an O, and none of them lasts long.

How to see it

Look for HR 2442 in the constellation Mon. At apparent magnitude 6.23, it is an easy target for binoculars.

Like any astronomical target, HR 2442 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 2442 is an epic variable star

HR 2442 scores 64 points on Spacedle's rarity scale, which places it in the epic tier. Another 14 points would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Distant (over 1,000 light-years), Blazing O-type star, Bright giant, Intrinsically luminous (Mv < −2), Barely variable (under 0.05 mag) 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.