#initial-load-header-loader { visibility: hidden!important; } #initial-load-content { visibility: visible!important; } .expandable .expandable-control { display: none!important; } .expandable .expandable-content { display: block!important; visibility: visible!important; max-height: none!important; height: auto!important; }

Messier number

noun Astronomy.

a number (preceded by M) designating the 109 double stars, clusters, nebulae, and galaxies in the Messier catalog.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019