Observer's guide
About NGC 4254
NGC 4254 (M99) is catalogued as a spiral galaxy in Coma Berenices. Its J2000 position is RA 12:18:49.60, Dec +14:24:59.4, corresponding to 184.7068 degrees RA and 14.4165 degrees Dec. The local catalogue places it about 60,000,000 light-years away. Its referenced angular extent is approximately 4.6 by 4.28 arcminutes.
Observing tips
This is rated as a hard target at magnitude 9.9. It is associated with spring observing, with midnight placement typically strongest around March. From 52 degrees north its theoretical meridian altitude is about 52.4 degrees; local horizons and the live altitude chart determine the practical window.
Because it is faint, use a larger aperture where possible, avoid bright Moon conditions, and use averted vision.
What to expect
The SIMBAD classification for the matched source is H2G. SIMBAD records the morphology as SA. A published radial velocity value is 2418 km/s. The SIMBAD record currently connects it to 1019 bibliographic references.
At roughly 4.6 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 4.6 by 4.28 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.