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Uncommon variable star 29 EP

HD 72257

RA 127.9225° · Dec -6.3188° · star

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Score breakdown

· 6 badges
29 pts · Uncommon
Uncommon 34 pts → Rare
  • Strongly variable +10
  • Distant (over 1,000 light-years) +6
  • Variable star +5
  • Yellow-white F-type star +3
  • A named variable star +3
  • Main-sequence star +2
Total score 29

5 more points to reach Rare.

Badges

  • Variable star · +5
  • Distant (over 1,000 light-years) · +6
  • Yellow-white F-type star · +3
  • Main-sequence star · +2
  • Strongly variable · +10
  • A named variable star · +3

Trivia

What it actually is

  • Spectral class. Its spectrum reads F5V + F5V — 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 9 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Hydra.
  • 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 January — that's when to go looking.

Could we get there?

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

Properties

absmag
1.43
bv
0.455
constellation
Hya
dist ly
1055.5211
luminosity
23.3346
mag
8.98
name
HD 72257
spect
F5V + F5V
var amplitude
0.6
var designation
VZ
var max
8.944
var min
9.544

About HD 72257

HD 72257 is an uncommon variable star. It lies about 1,055.5 light-years from Earth, sits in the constellation Hya, shines at apparent magnitude 8.98 and has spectral type F5V + F5V.

Its spectrum reads F5V + F5V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 72257 in the constellation Hya. At apparent magnitude 8.98, it is an easy target for binoculars.

Like any astronomical target, HD 72257 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 72257 is an uncommon variable star

HD 72257 scores 29 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 5 points would lift it into a rarer tier.

That score comes from 6 science badges — Variable star, Distant (over 1,000 light-years), Yellow-white F-type star, Main-sequence 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.