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Common variable star 15 EP

HD 128661

RA 219.2867° · Dec 35.9297° · star

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Score breakdown

· 5 badges
15 pts · Common
Common 22 pts → Uncommon
  • Variable star +5
  • Yellow-white F-type star +3
  • A named variable star +3
  • Main-sequence star +2
  • Barely variable (under 0.05 mag) +2
Total score 15

7 more points to reach Uncommon.

Badges

  • Variable star · +5
  • Yellow-white F-type star · +3
  • Main-sequence star · +2
  • Barely variable (under 0.05 mag) · +2
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads F0V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • 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 7.1 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Boötes.
  • 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 April — that's when to go looking.

Could we get there?

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

Properties

absmag
1.672
bv
0.128
constellation
Boo
dist ly
402.6618
luminosity
18.6724
mag
7.13
name
HD 128661
spect
F0V
var amplitude
0.05
var designation
BW
var max
7.115
var min
7.165

About HD 128661

HD 128661 is a common variable star. It lies about 402.7 light-years from Earth, sits in the constellation Boo, shines at apparent magnitude 7.13 and has spectral type F0V.

Its spectrum reads F0V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 128661 in the constellation Boo. At apparent magnitude 7.13, it is an easy target for binoculars.

Like any astronomical target, HD 128661 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 128661 is a common variable star

HD 128661 scores 15 points on Spacedle's rarity scale, which places it in the common tier. Another 7 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Yellow-white F-type star, Main-sequence star, 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.