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Common variable star 20 EP

HD 170470

RA 277.3085° · Dec 10.8921° · star

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Score breakdown

· 5 badges
20 pts · Common
Common 22 pts → Uncommon
  • Hot blue B-type star +6
  • Variable star +5
  • Gently variable +4
  • A named variable star +3
  • Main-sequence star +2
Total score 20

2 more points to reach Uncommon.

Badges

  • Variable star · +5
  • Hot blue B-type star · +6
  • Main-sequence star · +2
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads B9V — 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 7.9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Ophiuchus.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • 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
1.975
bv
0.05
constellation
Oph
dist ly
497.1889
luminosity
14.1254
mag
7.89
name
HD 170470
spect
B9V
var amplitude
0.43
var designation
V451
var max
7.857
var min
8.287

About HD 170470

HD 170470 is a common variable star. It lies about 497.2 light-years from Earth, sits in the constellation Oph, shines at apparent magnitude 7.89 and has spectral type B9V.

Its spectrum reads B9V — 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 HD 170470 in the constellation Oph. At apparent magnitude 7.89, it is an easy target for binoculars.

Like any astronomical target, HD 170470 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 HD 170470 is a common variable star

HD 170470 scores 20 points on Spacedle's rarity scale, which places it in the common tier. Another 2 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Hot blue B-type star, Main-sequence 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.