Messier 98

Lore & Background

Messier 98 was discovered by French astronomer Pierre Méchain in 1781, along with nearby M99 and M100, and was catalogued by compatriot Charles Messier 29 days later in his Catalogue des Nébuleuses & des amas d'Étoiles. It lies about 6° east of the bright star Denebola (Beta Leonis) in slightly northerly Coma Berenices.

The galaxy has a morphological classification of SAB(s)ab, indicating a spiral with mixed barred and non-barred features, intermediate to tightly wound arms, and no ring. It is highly inclined to the line of sight at an angle of 74° and has a maximum rotation velocity of 236 km/s. Its nucleus is active, displaying characteristics of a 'transition' type object, showing properties of a LINER-type galaxy intermixed with an H II region around the nucleus.

Messier 98 is a member of the Virgo Cluster, part of the local supercluster. About 750 million years ago, it may have interacted with the large spiral galaxy Messier 99; they are now separated by 1,300,000 light-years (400,000 parsecs).

Reader's Guide

Messier 98 is significant as a blueshifted galaxy, meaning it is moving toward the Milky Way at about 140 km/s, a rare characteristic among galaxies in the Virgo Cluster. Its intermediate spiral classification (SAB(s)ab) and high inclination of 74° provide valuable data for studying spiral structure and rotation dynamics. The galaxy's active nucleus, which blends LINER and H II region properties, offers insight into transitional galactic nuclei. Its possible past interaction with Messier 99 about 750 million years ago adds to understanding of galaxy interactions within clusters. As a member of the Virgo Cluster, it contributes to studies of cluster dynamics and the local supercluster. The galaxy's mass estimates—76 billion solar masses in stars, 4.3 billion solar masses in neutral hydrogen, and 85 million solar masses in dust—help characterize its composition. Its discovery by Pierre Méchain and cataloguing by Charles Messier in 1781 place it within the historic Messier catalogue, a foundational reference for deep-sky objects.

Did You Know?

• It was discovered by Pierre Méchain in 1781, along with M99 and M100.
• The galaxy may have interacted with Messier 99 about 750 million years ago.
• Its nucleus is a 'transition' type, showing both LINER and H II region characteristics.