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Uncommon star 32 EP

HD 71557

RA 127.0885° · Dec 6.7007° · star

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Score breakdown

· 6 badges
32 pts · Uncommon
Uncommon 34 pts → Rare
  • Intrinsically luminous (Mv < −2) +10
  • Distant (over 1,000 light-years) +6
  • White A-type star +5
  • Blue-white star +5
  • Star +3
  • On the zodiac +3
Total score 32

2 more points to reach Rare.

Badges

  • Star · +3
  • Distant (over 1,000 light-years) · +6
  • On the zodiac · +3
  • White A-type star · +5
  • Blue-white star · +5
  • Intrinsically luminous (Mv < −2) · +10

Trivia

What it actually is

  • Spectral class. Its spectrum reads A0 — 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.

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 7.4 it is just past naked-eye reach — ordinary binoculars will pull it in, over in Cancer.
  • 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.

Getting there

  • Aboard Voyager 1. ≈ 44.1 million years at Voyager 1's speed (17 km/s).
  • Fastest probe ever. ≈ 3.9 million years even at the Parker Solar Probe's 192 km/s.

Properties

absmag
-2.06
bv
-0.096
constellation
Cnc
dist ly
2508.8924
luminosity
580.7644
mag
7.37
name
HD 71557
spect
A0

About HD 71557

HD 71557 is an uncommon star. It lies about 2,508.9 light-years from Earth, sits in the constellation Cnc, shines at apparent magnitude 7.37 and has spectral type A0.

Its spectrum reads A0 — 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 71557 in the constellation Cnc. At apparent magnitude 7.37, it is an easy target for binoculars.

Like any astronomical target, HD 71557 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 71557 is an uncommon star

HD 71557 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 — Star, Distant (over 1,000 light-years), On the zodiac, White A-type star, Blue-white star and Intrinsically luminous (Mv < −2) — 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.