Messier 4 (The Cat's Eye) - Globular Cluster in Scorpius
Messier 4 is a Globular Cluster in the Scorpius constellation. Messier 4 is situated south of the celestial equator and, as such, it is more easily visible from the southern emisphere.
Photometric information of Messier 4
The following table lists the magnitude of Messier 4 in different bands of the electomagnetic spectrum (when available), from the B band (445nm wavelength, corresponding to the Blue color), to the V band ( 551nm wavelength, corresponding to Green/Yellow color), to the J, H, K bands (corresponding to 1220nm, 1630nm, 2190nm wavelengths respectively, which are colors not visible to the human eye).
For more information about photometry in astronomy, check the photometric system article on Wikipedia.
Apparent size of Messier 4The following table reports Messier 4 apparent angular size. The green area displayed on top of the DSS2 image of Messier 4 is a visual representation of it.
Digitized Sky Survey image of Messier 4
The image below is a photograph of Messier 4 from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.94x0.94 degrees (56.4x56.4 arcmins).
Celestial coordinates and finder chart of Messier 4
Celestial coordinates for the J2000 equinox of Messier 4 are provided in the following table:
The simplified sky charts below show the position of Messier 4 in the sky. The first chart has a field of view of 60° while the second one has a field of view of 10°.
Rise ans set times of Messier 4 from your location
Today's Messier 4 (The Cat's Eye) - Globular Cluster in Scorpius rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):