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Uncommon variable star 33 EP

66 Oph

RA 270.0658° · Dec 4.3686° · star

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Score breakdown

· 7 badges
33 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Hot blue B-type star +6
  • Variable star +5
  • Blue-white star +5
  • Gently variable +4
  • A named variable star +3
  • Main-sequence star +2
Total score 33

1 more point to reach Rare.

Badges

  • Variable star · +5
  • Naked-eye visible · +8
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Blue-white star · +5
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B2Ve — 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 on the main sequence, quietly fusing hydrogen in its core exactly as the Sun does.
  • 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 4.8 you can see it with your own eyes from a dark site, over in Ophiuchus.
  • 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 June — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Properties

absmag
-1.711
bv
-0.1
constellation
Oph
dist ly
651.01
luminosity
421.1143
mag
4.79
name
66 Oph
spect
B2Ve
var amplitude
0.17
var designation
V2048
var max
4.657
var min
4.827

About 66 Oph

66 Oph is an uncommon variable star. It lies about 651 light-years from Earth, sits in the constellation Oph, shines at apparent magnitude 4.79 and has spectral type B2Ve.

Its spectrum reads B2Ve — 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 66 Oph in the constellation Oph. At apparent magnitude 4.79, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 66 Oph 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 66 Oph is an uncommon variable star

66 Oph scores 33 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 1 point would lift it into a rarer tier.

That score comes from 7 science badges — Variable star, Naked-eye visible, Hot blue B-type star, Main-sequence star, Blue-white star, Gently variable 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.