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Uncommon variable star 26 EP

HD 221700

RA 353.6058° · Dec 7.9246° · star

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Score breakdown

· 6 badges
26 pts · Uncommon
Uncommon 34 pts → Rare
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • White A-type star +5
  • Gently variable +4
  • On the zodiac +3
  • A named variable star +3
Total score 26

8 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
  • Gently variable · +4
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads A3+... — 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 9.4 you'll want a small backyard telescope, over in Pisces.
  • 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 September — 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. ≈ 45.9 million years at Voyager 1's speed (17 km/s).

Properties

absmag
-0.135
bv
0.265
constellation
Psc
dist ly
2609.248
luminosity
98.6279
mag
9.38
name
HD 221700
spect
A3+...
var amplitude
0.09
var designation
Y
var max
9.335
var min
9.425

About HD 221700

HD 221700 is an uncommon variable star. It lies about 2,609.2 light-years from Earth, sits in the constellation Psc, shines at apparent magnitude 9.38 and has spectral type A3+....

Its spectrum reads A3+... — 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 221700 in the constellation Psc. At apparent magnitude 9.38, a small backyard telescope will bring it into view.

Like any astronomical target, HD 221700 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 221700 is an uncommon variable star

HD 221700 scores 26 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 8 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, 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.