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Uncommon variable star 32 EP

HD 120166

RA 206.9691° · Dec -0.5946° · star

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Score breakdown

· 6 badges
32 pts · Uncommon
Uncommon 34 pts → Rare
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • White A-type star +5
  • On the zodiac +3
  • A named variable star +3
Total score 32

2 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • On the zodiac · +3
  • White A-type star · +5
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads A2 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.
  • 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 10 you'll want a small backyard telescope, over in Virgo.
  • 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 April — that's when to go looking.

Could we get there?

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

Getting there

  • Aboard Voyager 1. ≈ 29.1 million years at Voyager 1's speed (17 km/s).

Properties

absmag
1.502
bv
0.139
constellation
Vir
dist ly
1655.6142
luminosity
21.8374
mag
10.03
name
HD 120166
spect
A2
var amplitude
0.68
var designation
BF
var max
9.946
var min
10.626

About HD 120166

HD 120166 is an uncommon variable star. It lies about 1,655.6 light-years from Earth, sits in the constellation Vir, shines at apparent magnitude 10.03 and has spectral type A2.

Its spectrum reads A2 — an A-type star: white-hot, typically about twice the Sun's mass, and the class most of the sky's famous bright stars belong to.

How to see it

Look for HD 120166 in the constellation Vir. At apparent magnitude 10.03, a small backyard telescope will bring it into view.

Like any astronomical target, HD 120166 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 120166 is an uncommon variable star

HD 120166 scores 32 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 2 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Distant (over 1,000 light-years), On the zodiac, White A-type star, Strongly 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.