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Epic black hole 56 EP

GRS 1124-684 (Nova Muscae 1991)

RA 171.6108° · Dec -68.6757° · blackhole

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Score breakdown

· 5 badges
56 pts · Epic
Epic 78 pts → Anomaly
  • Black hole +26
  • X-ray binary: stripping a living star +10
  • Has a proper name +8
  • Distant (over 1,000 light-years) +6
  • Stellar-mass black hole +6
Total score 56

22 more points to reach Anomaly.

Badges

  • Black hole · +26
  • Distant (over 1,000 light-years) · +6
  • Has a proper name · +8
  • Stellar-mass black hole · +6
  • X-ray binary: stripping a living star · +10

Trivia

What makes it special

  • It is feeding. Gas spiralling in is squeezed and heated to millions of degrees before it falls, so the disc around it blazes brighter than anything else in the neighbourhood.

Handle with care

  • Spaghettification. Its gravity pulls your feet so much harder than your head that you would be stretched into a thread roughly 813 km out — long before you ever reached the horizon.
  • No way back. Cross the event horizon and every path you could possibly take leads inwards. It is not that you cannot go fast enough — it is that 'out' has stopped being a direction.

What it actually is

  • Where it lives. It sits at the very heart of Milky Way.
  • What it is. A stellar-mass black hole: what is left behind when a star far heavier than the Sun exhausts its fuel and its core collapses in less than a second.
  • It is eating a star. It is stripping a living star: gas peels off its companion and spirals in, heated so fiercely on the way down that the disc glows in X-rays.

Sense of scale

  • In perspective. Far away by human standards, yet still a local address inside the Milky Way's spiral arms.
  • Its event horizon. The point of no return sits 32.5 km out, making the horizon about 65 km across.

Properties

accreting
yes
bh class
stellar
constellation
Mus
dist ly
16300
first imaged
no
gw detection
no
host galaxy
Milky Way
is sgr a
no
mass solar
11
name
GRS 1124-684 (Nova Muscae 1991)
named
yes
schwarzschild km
32.494
spin
0.63
xray binary
yes

Nearby objects

About GRS 1124-684 (Nova Muscae 1991)

GRS 1124-684 (Nova Muscae 1991) is an epic black hole. It lies about 16,300 light-years from Earth and sits in the constellation Mus.

Gas spiralling in is squeezed and heated to millions of degrees before it falls, so the disc around it blazes brighter than anything else in the neighbourhood.

How to see it

Look for GRS 1124-684 (Nova Muscae 1991) in the constellation Mus.

Like any astronomical target, GRS 1124-684 (Nova Muscae 1991) 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 GRS 1124-684 (Nova Muscae 1991) is an epic black hole

GRS 1124-684 (Nova Muscae 1991) scores 56 points on Spacedle's rarity scale, which places it in the epic tier. Another 22 points would lift it into a rarer tier.

That score comes from 5 science badges — Black hole, Distant (over 1,000 light-years), Has a proper name, Stellar-mass black hole and X-ray binary: stripping a living 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.