Messier 90
Encyclopedia
Messier 90 is a spiral galaxy
about 60 million light-year
s away in the constellation
Virgo
. It was discovered by Charles Messier
in 1781.
. The galaxy is located approximately 1°.5 away from the subgroup centered on Messier 87
. As a consequence of the galaxy's interaction with the intracluster medium
in the Virgo Cluster, the galaxy has lost much of its interstellar medium
. As a result of this process, which is referred to as ram pressure stripping, the galaxy's interstellar medium and star formation region
s appear truncated compared to similar galaxies outside the Virgo Cluster.
in Messier 90 appears truncated. Consequently, the galaxy's spiral arms appear to be smooth and featureless, rather than knotted like galaxies with extended star formation. However, the center of Messier 90 appears to be a site of significant star formation activity. Multiple supernovae in the nucleus have produced 'superwinds' that are blowing the galaxy's interstellar medium outward into the intracluster medium.
of Messier 90 is blueshifted, which indicates that it is moving towards the Earth. In contrast, the spectra of most other galaxies are redshift
ed. The blueshift was originally used to argue that Messier 90 was actually an object in the foreground of the Virgo Cluster. However, since the phenomenon was limited mostly to galaxies in the same part of the sky as the Virgo Cluster, it appeared that this inference based on the blueshift was incorrect. Instead, the blueshift is thought to be evidence for the large range in velocities of objects within the Virgo Cluster itself.
to estimate the distance to Messier 90.
(IC 3583) which is an irregular galaxy
.
Spiral galaxy
A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as...
about 60 million light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Virgo
Virgo (constellation)
Virgo is one of the constellations of the zodiac. Its name is Latin for virgin, and its symbol is . Lying between Leo to the west and Libra to the east, it is the second largest constellation in the sky...
. It was discovered by Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
in 1781.
Membership of the Virgo Cluster
Messier 90 is a member of the Virgo ClusterVirgo Cluster
The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly away in the constellation Virgo. Comprising approximately 1300 member galaxies, the cluster forms the heart of the larger Local Supercluster, of which the Local Group is an outlying member...
. The galaxy is located approximately 1°.5 away from the subgroup centered on Messier 87
Messier 87
Messier 87 is a supergiant elliptical galaxy. It was discovered in 1781 by the French astronomer Charles Messier, who cataloged it as a nebulous feature. The second brightest galaxy within the northern Virgo Cluster, it is located about 16.4 million parsecs from Earth...
. As a consequence of the galaxy's interaction with the intracluster medium
Intracluster medium
In astronomy, the intracluster medium is the superheated plasma present at the center of a galaxy cluster. This is gas heated to temperatures of between roughly 10 and 100 megakelvins and consisting mainly of ionised hydrogen and helium, containing most of the baryonic material in the cluster...
in the Virgo Cluster, the galaxy has lost much of its interstellar medium
Interstellar medium
In astronomy, the interstellar medium is the matter that exists in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, dust, and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space...
. As a result of this process, which is referred to as ram pressure stripping, the galaxy's interstellar medium and star formation region
Star formation
Star formation is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. As a branch of astronomy star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star formation process and the study of young...
s appear truncated compared to similar galaxies outside the Virgo Cluster.
Star formation activity
As stated above, the star formationStar formation
Star formation is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. As a branch of astronomy star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star formation process and the study of young...
in Messier 90 appears truncated. Consequently, the galaxy's spiral arms appear to be smooth and featureless, rather than knotted like galaxies with extended star formation. However, the center of Messier 90 appears to be a site of significant star formation activity. Multiple supernovae in the nucleus have produced 'superwinds' that are blowing the galaxy's interstellar medium outward into the intracluster medium.
Blueshift
The spectrumSpectrum
A spectrum is a condition that is not limited to a specific set of values but can vary infinitely within a continuum. The word saw its first scientific use within the field of optics to describe the rainbow of colors in visible light when separated using a prism; it has since been applied by...
of Messier 90 is blueshifted, which indicates that it is moving towards the Earth. In contrast, the spectra of most other galaxies are redshift
Redshift
In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum...
ed. The blueshift was originally used to argue that Messier 90 was actually an object in the foreground of the Virgo Cluster. However, since the phenomenon was limited mostly to galaxies in the same part of the sky as the Virgo Cluster, it appeared that this inference based on the blueshift was incorrect. Instead, the blueshift is thought to be evidence for the large range in velocities of objects within the Virgo Cluster itself.
Distance measurements
Low levels of H I gas prevents using the Tully-Fisher relationTully-Fisher relation
In astronomy, the Tully–Fisher relation, published by astronomers R. Brent Tully and J. Richard Fisher in 1977, is an empirical relationship between the intrinsic luminosity of a spiral galaxy and its velocity width...
to estimate the distance to Messier 90.
Companion galaxies
Messier 90 has PIE satellite galaxySatellite galaxy
A satellite galaxy orbits a larger galaxy due to gravitational attraction. Although a galaxy is made of a large number of objects which are not connected to each other, it has a center of mass, which represents a weighted average of the positions of each component object...
(IC 3583) which is an irregular galaxy
Irregular galaxy
An irregular galaxy is a galaxy that does not have a distinct regular shape, like a spiral or an elliptical galaxy. The shape of an irregular galaxy is uncommon – they do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a...
.