Tukuk-OS🔭 M93 — Critter Cluster
Open cluster in Puppis
M93, Critter Cluster is a open cluster in the constellation Puppis, with an apparent magnitude of about 6, roughly 3.6 thousand light-years away.
Data
| Catalogue designation | M93 |
|---|---|
| Common name | Critter Cluster |
| Object type | Open cluster |
| Constellation | Puppis |
| NGC / IC | NGC 2447 |
| Apparent magnitude | 6 |
| Distance (approx.) | 3.6 thousand light-years |
What a open cluster is
A loose, young family of a few dozen to a few thousand stars born together from the same gas cloud and drifting apart over time. The Pleiades are the most famous example.
How far is M93, really?
The catalogue puts M93 at roughly 3.6 thousand light-years away — about 1,104 parsecs. A light-year is the distance light covers in one year, some 9.46 trillion kilometres, so this is how long the light now entering your eyes has been travelling. For scale: about 1.8 times the span since the start of the Common Era. A message sent there today would need to wait twice that many years for a reply, which is why astronomers always look backwards: every telescope is a time machine with the dial set by distance.
What will show it to you?
M93 carries an apparent magnitude of about 6. bright enough for the naked eye from a genuinely dark site — look for it on a moonless night far from town lights. The magnitude scale runs backwards — smaller is brighter, and each whole step is a factor of about 2.5 in light — so 6 is the traditional naked-eye ceiling on a good night, and every number below it is progressively easier.
Finding its home constellation
M93 lies inside the official borders of Puppis, whose name means “poop deck”, a region of 673 square degrees. Practical way to find it: learn Puppis’s pattern first — its brightest star, Naos, is the anchor point, then star-hop from there. The constellation’s own page lists every other Messier object that shares its borders, which usually means a night’s hunting is hiding in one patch of sky.
Other Messier objects in Puppis: M46, M47.
More open clusters in the catalogue: M6 · M7 · M11 · M18 · M21 · M23 · M25 · M26 · M29 · M34 … and 15 more on the Messier hub. The full catalogue groups all 110 the same way.