Observer's guide
About Jewel Box
Jewel Box (C94) is catalogued as an open cluster in Crux. Its J2000 position is RA 12:53:42, Dec -60:21:00, corresponding to 193.415 degrees RA and -60.3711 degrees Dec. The local catalogue places it about 4,900 light-years away. Its referenced angular extent is approximately 10.3 by 10.3 arcminutes.
Observing tips
This is rated as a very easy target at magnitude 4.2. It is associated with spring observing, with midnight placement typically strongest around March. From 52 degrees north its theoretical meridian altitude is about 0 degrees; local horizons and the live altitude chart determine the practical window.
Its brightness makes it a practical binocular or small-telescope candidate when it is well above the horizon.
What to expect
The SIMBAD classification for the matched source is OpC. A published radial velocity value is -20 km/s. The SIMBAD record currently connects it to 301 bibliographic references.
At roughly 10.3 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 10.3 by 10.3 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.